Model 845-M User Manual

Model 845-M Key Specifications

The Model 845-M is a wideband low phase noise synthesizer operating from 10 MHz to 20 GHz, packaged as a compact flange-mount module. The nominal output power is +23 dBm. The module has milli-Hz frequency resolution and uses a high-stability internal reference that can be phase-locked to a user-settable external reference. For highest phase coherence, multiple 845-M modules can be cascaded with one master reference clock. Operated from a single 6 V DC supply, it consumes less than 20 watts. The values below are drawn from the Model 845-M datasheet, which is authoritative for 845-M specifications.

Warranty and Copyright

Warranty. All Berkeley Nucleonics (BNC) instruments are warranted against defects in material and workmanship for a period of two years from the date of shipment. Berkeley Nucleonics will, at its option, repair or replace products that prove to be defective during the warranty period, provided they are returned to Berkeley Nucleonics and provided the preventative maintenance procedures are followed. Repairs necessitated by misuse of the product are not covered by this warranty. No other warranties are expressed or implied, including but not limited to implied warranties of merchantability and fitness for a particular purpose. Berkeley Nucleonics is not liable for consequential damages. The warranty on the internal rechargeable batteries (option B3) is one year from the date of shipment. Battery replacement is available through Berkeley Nucleonics and its distributors.

Copyright. This manual is copyright by Berkeley Nucleonics and all rights are reserved. No portion of this document may be reproduced, copied, transmitted, transcribed, stored in a retrieval system, or translated in any form or by any means such as electronic, mechanical, magnetic, optical, chemical, manual or otherwise, without written permission of Berkeley Nucleonics.

1. General Remarks

The devices described in this manual are signal generators that produce electromagnetic signals from 9 kHz up to 40 GHz with a power from -90 dBm up to +25 dBm. The exact range depends on the chosen device model and options. The devices can produce different types of modulations, such as AM, FM, PM, Pulse or Chirp.

They can be used in a variety of applications such as research and development or manufacturing and testing of electronic components.

Options, such as a 1U Case, an internal rechargeable battery, a GPIB interface or different types of power range extensions can be added.

1.1 Validity of this Manual

This manual is valid for the following devices and their extended versions:

• 835-4/6
• 845-12/20/26
• 865B-6/12/20/26/40
• 871
• 825-M, 845-M, 865B-M
• 845-M-X, 865B-M-X
• 855B-6-X, 12-X, 20-X, 33-X, 40-X
• 805-M

2. Available Casing

The devices are available in the following cases.

2.1 Compact Portable Case (CPC)

Figure 1: 845-26, 865B-40, and 870A in a Compact Portable Case (with LCD and touch display, respectively).

2.2 1U Case

2.3 Desktop Chassis

2.4 Module

The Model 845-M ships as a compact flange-mount module, the form factor featured by this manual. The module measures 10.5 x 21 x 6 cm and weighs no more than 1.0 kg net. With Option 1URM the module is supplied in a 19 inch 1HU rackmount enclosure.

3. Connections and Transportation

3.1 Data Connections

The devices may only be connected to a network or a computer by using a shielded LAN cable. Unless shorter lengths are prescribed, a maximum length of 3 m must not be exceeded for the LAN and the USB connection.

3.2 Signal Connections

In general, all connections between the signal generator and another device should be made as short as possible and must be well shielded. It is recommended to use a high-quality cable with low loss especially for frequencies above 20 GHz.

3.3 Transportation

The devices must only be transported with the packaging supplied by the manufacturer. The device can be lifted up or transported in any orientation.

4. Safety Information

The following pieces of information are important to prevent personal injury, loss of life or damage to the equipment. Please read them carefully. If the device is used in a manner not specified by this manual, the protection provided by the device may be impaired.

4.1 Signal Symbol

In this manual, the following symbols are used to warn the reader about risks and dangers.

4.2 Labels on Products

The following labels are on the products. Familiarize yourself with the meaning of each of the labels before using the product.

Symbol	Meaning
	Direct Current (DC)
	Alternating Current (AC)
	Earth (Ground)
	EU label for separate collection of electrical and electronic waste.
	Caution, general danger zone. Attend the manual and/or a notice on the device.

4.3 General Safety Considerations

FCC notice

This equipment has been tested and found to comply with the limits for a Class A device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications.

Operation of this equipment in a residential area may cause harmful interference in which case the user will be required to correct the interference at his or her expense.

CE notice. The instrument meets the EMC directive and the Low Voltage Directive described in the CE declaration in Appendix A. The instrument is CE marked.

5. Technical Specifications

Model-specific frequency, output power and phase-noise figures are given on the Model 845-M datasheet and take precedence over any family-generic values shown here. The mechanical, connector, environmental and power figures below apply to the shared 800-series enclosures; the 845-M module dimensions and connectors are summarized in the Key Specifications block above and detailed on the datasheet.

5.1 Dimensions

5.1.1 CPC

Dimensions of the compact portable case:

5.1.2 1U

Dimensions of the 1U:

5.2 Connectors

5.2.1 CPC

The front panel contains a status display (only in CPC), RF output female N-type connector (835), a female SMA connector (845, 865B-6,12,20,26,40, 855B, 845-M, 865B-M), or a K connector (865B-40) and an RF on/off key.

Front panel (Model 845-26)

1. Main LCD display. The main display shows the following information:
   • 1st line: RF frequency in Hz
   • 2nd line: RF amplitude in dBm
   • 3rd line: Frequency reference status (internal, external, lock status)
   • 4th line: Remote control status
2. Rotary Button. The rotary button is used to change the value selected on the screen.
3. RF 50 Ω connector. This female N-type connector respectively SMA connector provides the output for generator signals. The impedance is 50 ohm. The reverse power damage level is +30 dBm maximum. The maximum allowed DC level is +/- 30 dBm maximum.
4. Menu Buttons. The menu buttons are used to change the selected menu point or value.
5. Main Menu Button. The main menu button is used to enter the menu.
6. RF On/Off button. The ON/OFF key toggles between RF output on and RF output off. The green light is indicating whether the RF output is enabled or not.
7. Remote LED. The remote LED is indicating whether the device connected to a Computer or not.
8. Power LED. The power LED is indicating whether the device is connected to a Computer or not.

Rear panel (Model 845-26)

1. ΦM. This BNC female connector is the input for FM and PM.
2. REF IN. This BNC female connector is the input for the reference signal.
3. TRIG IN. This BNC female connector is the trigger input.
4. USB B. The USB B connector is used to connect the device to a computer.
5. LAN. The LAN connector is used to connect the device to a network.
6. Battery LED. In case the device has a rechargeable battery, this LED indicates whether the battery is charged or not.
7. Fan Holes. The holes by which the air is intaken.
8. Power Supply. Apply the BNC power adaptor to this connector to supply the device with energy.
9. On/Off Switch. Turns the device on or off.
10. Ground Screw.
11. FUNC OUT. This BNC female connector is the output for the function signal.
12. REF OUT. This BNC female connector is the output for the reference signal.
13. AM PULSE. This BNC female connector is the input for the AM and the PULSE Modulation signal.
14. Fan Holes. The holes by which the air is extruded.

5.2.2 1U: 845

Front panel

1. ON/OFF Switch. Turns the device on or off.
2. Power LED. The power LED is indicating whether the device is on or off.
3. Remote LED. The remote LED is indicating whether the device connected to a Computer or not.
4. Fan Holes. The holes by which the air is intaken.
5. RF 50 Ω connector. This female SMA connector respectively the female N-type connector provides the output for generator signals. The impedance is 50 ohm. The reverse power damage level is +30 dBm maximum. The maximum allowed DC level is +/- 10 V. Please check the data sheets for more details.

Rear panel

1. Ground Screw.
2. GPIB Connector. In case the device has the option "GPIB", on this position the GPIB connector is.
3. USB B. The USB B connector is used to connect the device to a computer.
4. LAN. The LAN connector is used to connect the device to a network.
5. Fuse Holder. This holder contains an exchangeable fuse.
6. Power Supply. Apply the BNC power adaptor to this position, the AC connector, to supply the device with energy.
7. REF IN. This BNC female connector is the input for the reference signal.
8. REF OUT. This BNC female connector is the output for the reference signal.
9. TRIG IN. This BNC female connector is the trigger input.
10. ΦM. This BNC female connector is the input for FM and PM.
11. PULSE. This BNC female connector is the input for the pulse signal.
12. FUNC OUT. This BNC female connector is the output for the function signal.
13. AM PULSE. This BNC female connector is the input for the AM and the PULSE Modulation signal.

5.2.3 1U: 855B / 865B-M-40-X

Front panel

1. ON/OFF Switch. Turns the device on or off.
2. Power LED. The power LED is indicating whether the device is on or off.
3. Remote LED. The remote LED is indicating whether the device connected to a Computer or not.
4. Channel 1: PULSE. This BNC female connector is the input for the PULSE Modulation signal.
5. Channel 1: RF OUT. This female SMA connector provides the output for the PULSE Modulation signal.
6. Channel 2
7. Channel 3
8. Channel 4
9. RF 50 Ω connector. This female K-type connector provides the output for the RF signals. The impedance is 50 ohm. The reverse power damage level is +30 dBm maximum. The maximum allowed DC level is +/- 10 V. Please check the data sheets for more details.

Rear panel

1. Ground Screw.
2. Sync In port. Unit-to-unit synchronization signal input. SMA female.
3. Sync Out port. Unit-to-unit synchronization signal output. SMA female.
4. CLK IN. External 3GHz reference input. SMA female.
5. CLK OUT. Internal 3GHz reference output. SMA female.
6. TRIG OUT. This BNC female connector is the trigger output.
7. TRIG IN. This BNC female connector is the trigger input.
8. REF OUT. This BNC female connector is the output for the reference signal.
9. REF IN. This BNC female connector is the input for the reference signal.
10. GPIB Connector. In case the device has the option "GPIB", on this position the GPIB connector is.
11. LAN. The LAN connector is used to connect the device to a network.
12. USB B. The USB B connector is used to connect the device to a computer.
13. Fuse Holder. This holder contains an exchangeable fuse.
14. Power Supply. Apply the BNC power adaptor to this connector to supply the device with energy.

5.2.4 CPC with Touch display

The front panel contains a touch display. RF output female SMA connector (845, 865B-6/12/20/26, 855B, 845-M, 865B-M) or a K connector (865B-40) and any kind of error and other messages. Information includes status indicators, frequency and amplitude settings, current connectivity status, and error messages.

Front panel

1. Main touch display. The main display shows information on the current function, such as frequency, power, reference.
2. Rotary Button. The rotary button is used to change the value selected on the screen.
3. RF 50 Ω connector. This female SMA respectively K connector provides the output for generator signals. The impedance is 50 ohm. The reverse power damage level is +30 dBm maximum. The maximum allowed DC level is +/- 10 V. Please check the data sheets for more details.

Rear panel

1. REF IN. This BNC female connector is the input for the reference signal.
2. MOD IN. This BNC female connector is the input for the modulation signal.
3. TRIG IN. This BNC female connector is the trigger input.
4. USB B. The USB B connector is used to connect the device to a computer.
5. LAN. The LAN connector is used to connect the device to a network.
6. Fan Holes. The holes by which the air is intake.
7. Power Supply. Apply the BNC power adaptor to this connector to supply the device with energy.
8. ON/Off Switch. Turns the device on or off.
9. Ground Screw.
10. TRIG OUT. This BNC female connector is a multi-function output.

5.3 Minimum Distances

The minimum distances are:

5.4 Energizing and de-Energizing

To energize the device, apply the following voltage to the following connector.

The 1U case has a fuse, accessible from the outside. To change the fuse, pull out the mains plug, push the fuse holder into the back panel and turn it around 45 degrees, then take the holder out. Replace the old fuse with a new one. It is forbidden to repair defect fuses or to bridge them by any means. Use only a fuse with the following specifications.

Type of fuse:

• Size. 5 x 20 mm
• Voltage. 250 V
• Current rating. 3.15 A
• Characteristic. Time-Lag T
• Breaking capacity. 35 A to 200 A

5.5 Proper operation conditions

The devices are designed for use in dry and clean environments. The CPC can also be used in field as long as the operating conditions are met. Operation in an environment with high dust content, high humidity, danger of explosion or chemical vapors is prohibited.

• Operating temperature range. 0°C to +45°C.
• Storage and transportation temperature range. -40°C to +70°C.
• Operating and storage altitude. 4600 m. In case of condensation 2 hours are to be allowed for drying prior operation. Operation is only allowed from a 3-terminal mains connector with a safety ground connection and a mains plug used in your specific country. For sufficient ventilation, ensure open ventilation holes.

5.6 Environmental Information

1. Waste electrical and electronic equipment must not be disposed of with unsorted municipal waste, but must be collected separately. Contact the BNC customer service center for environmentally responsible disposal of the product.
2. Specially marked equipment has a battery or accumulator that must not be disposed of with unsorted municipal waste, but must be collected separately. It may only be disposed of at a suitable collection point or via BNC service center.

6. Introduction

This instruction manual is valid for BNC model series 835, 845, 865B, 855B 845-M, and 865B-M. Chapter 4 gives guidance for a quick and easy setup of your new instrument. Chapter 5 describes the remote operation via BNC graphical user interface (GUI). Chapter 6 describes control via front panel and applies only to 835/845 models.

6.1 Included Material

Your signal generator kit contains the following items:

• Signal Generator
• Universal power adaptor (AC 100 to 240V) with corresponding country specific plugs
• Ethernet Cable
• Manuals and software CD

6.2 General Features and Functions (Model overview)

BNC RF and Microwave Signal Generator model overview.

General features include:

• Extendable power range (option PE3, PE4)
• Modulation capabilities for AM, FM, PM and PULM modulation (model dependent)
• Fast frequency, power and list sweeps
• Light weight, optional internal rechargeable batteries (options B3, EBAT)
• 3-inch status LCD (835/845 models only)
• Long-term support. Software upgrades (firmware, API, GUI) are available to download from www.berkeleynucleonics.com. You can also call our technical specialists for support. You can continue to use both of these services free of charge for the lifetime of the product.
• Universal LAN VXI-11 and USB 2.0 device and host interface
• 18-24 months calibration cycle

6.3 Options

• B3. Internal rechargeable battery
• FS. Fast switching
• LN. Enhanced close in phase noise
• MOD. Analogue modulation
• PE3. Mechanical step attenuator for extended power range

• PE4. Electrical step attenuator for extended power range

• GPIB. GPIB interface added
• AVIO. Specific avionics modulation capabilities added (Model 835)
• 1U. 19'' 1HE enclosure. No display, remote control only
• RM. 19'' 3HU rack-mount kit
• REAR. Move output to the rear
• 9K. Frequency range extension to 9 kHz
• HP. High output power
• TP. Color touch-screen front panel
• LH. Desktop housing with color touch-screen front panel
• NM. Remove modulation function
• EB. External power bank
• PHS. Phase coherent switching
• VREF. Variable external reference

7. Getting Started

7.1 System Requirements

7.2 Unpacking the Instrument

Remove the instrument materials from the shipping containers. Save the containers for future use.

For a list of material included in the standard package, please refer to chapter 4.1.

7.3 Initial Inspection

Inspect the shipping container for damage. If container is damaged, retain it until contents of the shipment have been verified against the packing list and instruments have been inspected for mechanical and electrical operation.

7.4 Starting the Instrument

This section describes installation instructions and verification tests.

7.4.1 Applying Power

Press the line on/off switch on the rear panel. If available, the front panel display will illuminate. The instrument will initialize and momentarily display the model number, firmware revision and product serial number. The display will then switch to the factory default display setting, showing preset frequency (100 MHz) and power (0 dBm), phase lock status (of internal reference) and instrument connectivity status. (Ethernet IP or USB Identifier).

Note, the instrument booting process may take up to 60 seconds (depending on configuration) to complete.

7.4.2 Connecting to LAN

Connect the instrument to your local area network (LAN) using the Ethernet cable. By default, the instrument is configured to accept its dynamic IP number from the DHCP server of your network. If it is configured properly, your network router will assign a dynamic IP number to the connection to your network so that the instrument can be automatically detected and connected to the network. Your instrument is now ready to receive remote commands.

7.4.3 Direct connectivity to host via Ethernet cable (no router)

You can connect to the instrument to your computer with the Ethernet cable without using a local area network with DHCP server. To work properly, the network controller (NIC) of your computer must be set to a static IP address in the ZEROCONF standard, beginning with 169.254.xxx.xxx (excluding 169.254.255.255) and ending with 169.254.255.254. Use the network mask 255.255.0.0. Some operating systems will not start a NIC unless connected to a network with a DHCP server, even if a fixed IP address is assigned. In that case, connect via the local area network instead.

7.4.4 Connecting through USB

Connect the instrument to the computer using a quality USB type-A to type-B cable. If properly connected, the operating system should automatically install a USBTMC device.

Note that if you want to use the USB BNC, it must be installed (or comparable) must be installed.

Use VISA Write to send the *IDN? Query and use VISA Read to get the response. The USBTMC protocol supports service request, triggers and other USB-specific operations.

7.4.5 Connecting through GPIB

Connect the instrument to the GPIB controller using the rear panel GPIB connector (option GPIB is required). Once connected properly, use VISA Write to send the *IDN? Query and use VISA Read to get the response. The protocol supports service request, triggers and other GPIB-specific operations.

7.4.6 Installing the 835/845 Remote Client

BNC's graphical user interface provides an intuitive control of the instruments. It runs under Windows operating system with minimum requirements. The DLL is embedded in the GUI application and requires the Microsoft .NET framework. The setup program guides you in a few steps through the installation process. In case the NET framework is not installed on your computer, then you need to install it manually. After installation the program will start.

7.4.7 Troubleshooting the LAN Interconnection

Software does not install properly

• Make sure your installation CD is not damaged.
• When Microsoft .NET Framework is not installed make sure that your computer is connected to the internet during installation of the BNC Software. If no internet connection is available, install the .NET Framework that is available on the installation CD.

Software cannot detect any instrument

• Make sure you have connected both computer and instrument to a common network.
• If a direct connection is used you may require to reset your computer Ethernet controller (depending on the configuration). Note that in that case detection of the instrument can take a considerable amount of time if your computer is configured to work with an external DHCP server. In some cases the detection may even fail completely. Configure your computer network controller to an appropriate fixed IP instead.
• Make sure that your software firewall enables the GUI to setup a TCP/IP connection via the LAN. Under Windows 7/10 you can do that like this: Open Control Panel under Settings in your Start menu. Then go to Windows Firewall. Click on Exceptions and then add Program. If the GUI is in this list, choose it and click OK otherwise you have to browse for the path to GUI installation directory. Finally close all open dialogs with OK. Now your Windows Firewall will not block requests from the GUI.

7.4.8 Shutting Down the Signal Generator

Press the line on/off switch on the rear panel to off.

8. Using the Graphical User Interface (GUI)

BNC's graphical user interface provides an intuitive control of the signal generator. It runs under any Windows operating system. Make sure the software is installed correctly and the computer's firewall is configured properly. The GUI's dynamic link library (DLL) uses the Microsoft .NET framework.

8.1 Start the Signal Generator (SG) GUI

After successful installation of the software double-click the software shortcut that has been created on your desktop.

After start, the GUI will automatically detect existing BNC instruments that are connected to the computer (network) via local area network, USB, or GPIB. In the CONTROL tab (see Figure 6-a) the detected instruments are listed. Clicking on one of the devices will instantly establish connection. Clicking on an alternate device will disconnect the old device and reconnect to the new device. Scan Instruments button will enable automated scanning for new instruments. Disconnect/Connect button will establish and terminate connection.

8.2 General Look

1. The CONTROL tab (Figure 6-a) completes the following function:
   • Scan and establish connection to instrument
   • Configure remote interface (LAN, USB, GPIB)
   • Save, load and manage instrument memory states
2. CW tab
3. SWEEP tab
4. MODULATION Tab
5. REFERENCE Tab
6. TRIGGER Tab
7. LF OUT Tab

8.3 Simultaneously controlling Multiple Signal Generators from one PC

You can easily control multiple BNC instruments from a single computer but you need to start a separate GUI for every instrument as only one instrument is controlled by the GUI at once.

8.4 Store and Load Instrument States

Multiple memory states are available to store instrument settings. By clicking on the Device Settings Memory button the currently saved memory settings are displayed and can be retrieved or shown on a separate dialog 6. To modify or enter a state, click on the appropriate line and select if the current instrument settings should be stored or loaded into the selected memory state.

The memory states can also be accessed via the front panel menu.

8.5 Setting Network Configuration

The Network Configuration button allows configuring the LAN settings as shown in Figure 6-c. You may choose from three different network addressing modes: setting to Auto will check for a DHCP server on the network but if this fails, will fall back to assigning an address automatically using zeroconf. Setting to DHCP will check for a DHCP server on the network (without a fallback) and Manual will require to supply all network settings for the device manually below. Additionally, the device name and revision are displayed at the bottom of the dialog box.

8.6 Multi-Session Option

The "Multi-Session" checkbox can be selected to enable the device to be accessed from more than one instance of the UI. This enables users on multiple computers on the network to connect to and configure the device simultaneously. It is the user's responsibility to manage access conflicts whilst this mode is enabled (i.e. 2 users changing the same option from different PCs).

8.7 Device Port Setting

The "Port" option allows the listening TCP port to be customized for the device. The default setting for all devices is port 18. If changed, the device will no longer be accessible using this port number. Any instances of the UI (or other VISA applications connecting to the device over a network) will need to modify their destination port number to match the device to connect to.

8.8 Connecting to devices using a non-default port

There are 2 options for connecting to a device when its default listening port has been changed.

1. Specify a temporary connection port. Click the menu Info → Connection Settings → Specify Connection Port. This will cause a new setting "Custom Port" to be displayed on the "Control" tab of the UI (see Figures 6-d and 6-e). The connection port to use can then be entered (within the range of permissible TCP port numbers). Beware that this setting will overwrite the default port until it is removed. To remove, click the menu Connection Port setting from the UI and reset the value using the current default port. Deleting the port number from the "Custom Port" text box will also cause the UI to revert to using the default port.
2. Change the application's default port setting. The global default port to use for connections can be changed by selecting menu Info → Connection Settings → Change Default Port (see figure 6-d). A default port can be entered into the dialog box which appears and set by clicking button "Set Default" only permissible TCP ports can be entered here. If the new default port is entered, then the new default port setting. Deleting the port number from the default setting will use the current default port as before, including after restarting the UI or rebooting your system.

8.9 Setting the GPIB Address

If the instrument has the GPIB option installed, the GPIB address can be changed in the GPIB submenu in the control tab. Valid GPIB addresses range from 1 to 30. To verify GPIB functionality, use the VISA Assistant available with the Agilent IO Library or the Getting Started Wizard available with the National Instrument IO Library. These utility programs enable you to communicate with the signal generator and verify operation. For information and instructions on running these programs refer to the Help menu available in each utility.

8.10 Perform Firmware Upgrade

A firmware upgrade of the instrument can be done directly via the GUI. First make sure you are connected to the right instrument and have the correct firmware files (.tar) ready. Then apply Controller → Update Firmware and select the appropriate binary file that you have received from BNC or downloaded from the BNC website. The update will take a few seconds and after completion your instrument will reboot. Reconnect to the instruments after booting is completed and continue with the updated firmware.

8.11 Multi-Output GUI Control

Individual outputs of the BNC multi-channel signal sources (such as 855B or 865B-M-40-X) can be controlled by the GUI by selecting the corresponding channel above the control tab menu. Each channel can be configured fully independently as if they were individual signal generators. Note that the "Select Channel" appears only when connected to a multi-channel device.

9. Local Operation via Front Panel

Most of the signal generator models offer direct front panel control. A rotary knob and five keys (MENU), and four arrow keys allow full control over the instrument. Figure 7-a shows the front panel of the 835/845, Figure 7-b shows the front panel of the 865B (resp. 835/845 with option TP).

For both Front panels:

• RF 50 Ω connector. This female N-type connector provides the output for RF signals. The impedance is 50 ohm. The damage level is +30 dBm. The maximum allowed power level is +/- 10 V.

Only for 835/845 front panels:

• RF On/Off button. The ON/OFF key toggles between RF output on and RF output off. The green light is indicating whether the RF output is on or off.
• Menu Key. This is a multifunction key. The key is used to enter and exit menus. Press once to return to the CW menu, multiple times to toggle between the selected submenu and the CW menu.

You can always be exit by pressing the menu key.

The four arrow keys are used to move cursor within the screen menus. Within menus, the up/down keys are used to enter (1) and exit (2) menu items or, when editing, increment or decrement a value. The left/right keys are used in next parameter hierarchy (3) in next menu hierarchy (4). The arrow keys are used to navigate between menu pages where pages exist and to navigate through the lists.

The LAN LED illuminates when a remote connection is made.

Power LED illuminates when system is powered up.

The currently active display position is shown by the cursor (underline symbol, or different background colour). The cursor does not move beyond the field of the currently selected parameter. Rotate the front panel knob to modify the value. Clockwise rotation increases the value while counter-clockwise rotation decreases the parameter. The maximum or minimum limit of the parameter.

9.1 Displayed Parameter Formats

The following sections describe how to control the instrument via the front panel control by invoking various menu functions.

9.2 CW Display

The Main or CW Display is shown after the instrument has successfully booted and is ready. The four line display has the following format:

9.3 Main Menu Display

The Main Menu Display is invoked by pressing the menu key. The main menu contains nine submenus as shown below.

1. Sweep
2. Modulation
3. Reference
4. Trigger
5. LF Output
6. LAN Config
7. Display Settings
8. Device Settings
9. Help

9.4 Frequency Sweep Submenu

After accessing the Frequency Sweep menu, first of three displays allows to enter the start and stop frequency. On the second display the number of points and the on and off time can be entered. On the third screen select the sweep mode between Linear, LOGarithmic and RANDom. Also select the repetition mode between INFinite and 1 (single repetition).

Start the sweep by pressing the RF On/Off button.

9.5 Power Sweep Submenu

After accessing the Power Sweep menu, the first display allows to enter start and stop power. On the second display, the number of points and the on and off time can be entered. On the third display, select the repetition mode between INFinite, and 1 (single repetition).

Start the sweep by pressing the RF On/Off button.

Figure 7-p: Displays shown for the frequency sweep configuration.

9.6 List Sweep Submenu

When entering the List Sweep submenu, a list of stored list sweeps is displayed.

9.7 Modulation Submenu

On line 1 select between INT (internal pulse generator) and EXT (external input). If internal modulation (INT) is selected, go to line 2 to change pulse width to desired value and go to line 3 to change pulse modulation frequency.

9.7.1 Pulse Modulation Submenu

On line 1 select between INT (internal pulse generator) and EXT (external input). If internal modulation (INT) is selected, go to line 2 to change pulse width to desired value and go to line 3 to change pulse modulation frequency.

9.7.2 Amplitude Modulation Submenu

In the Amplitude Mod submenu the internal amplitude modulation can be accessed. The modulation rate can be set between 1 Hz and 10 kHz.

9.7.3 Frequency Modulation Submenu

In the Frequency Mod submenu the internal and external frequency modulation can be accessed. It is possible to change between internal and external modulation source and to change modulation parameters such as modulation rate, depth or sensitivity.

9.7.4 Phase Modulation Submenu

In the phase modulation submenu the internal and external phase modulation can be accessed. It is possible to change between internal and external modulation source and change modulation parameters.

9.8 Reference Submenu

After accessing the Reference menu, use the rotary knob to toggle between ON and OFF or to change reference frequency to the desired value, respectively.

9.9 Trigger Submenu

After accessing the Trigger menu, use the rotary knob to toggle the selected entry value or to change selected digit. The display shows up to six selected entries.

• Select SOURce. IMMediate, EXTernal, BUS (SCPI command), KEY (RF on/off button)
• Select SLOPe. POSitive, NEGative
• Select CONTinuous. ON, OFF (ON means that the trigger is re-armed after each trigger occurrence)
• Select RETRigger. OFF, ON, IMMediate (OFF means that any trigger event during execution of list is ignored)

Enter DELAY: trigger delay in micro seconds.

Press the RF On/Off button to arm the trigger. Exit the menu by pressing the menu key.

9.10 LF OUTPUT Submenu

In the LF OUTPUT Submenu the FUNCT OUT output can be configured at the rear panel of the instrument. On the first screen source for the FUNCT OUT can be selected. Choose LFG for the low frequency generator, TRIG to enable the instrument trigger output and PULSE to enable the pulse modulation in DC level is +/- 10 V. The source for the device frequency and voltage amplitude.

9.11 LAN Configuration Submenu

In the LAN Configuration menu, IP address, subnet mask and DHCP can be configured. Press the RF key to save the configuration (don't if you want to discard your changes).

9.12 Display Settings Submenu

After accessing the Display Configuration menu, use the rotary knob to change the display contrast as required. Press the menu key to save and exit the Display Settings submenu.

9.12.1 Save Settings Submenu

After accessing the Load Settings menu, use the rotary knob to get to the memory state you want to save. Press RF ON/OFF key to save your settings.

9.12.2 Load Settings Submenu

After accessing the Load Settings menu, use the rotary knob to get to the memory state you want to load. Press RF ON/OFF key to load.

9.12.3 Load Defaults Submenu

Press RF ON/OFF key button to load.

9.13 Help Submenu

This submenu provides basic information about the front panel menu control.

10. Combined Modulation

The tables below show what modulation types and sweeps can be active simultaneously.

Some modulations can be combined with frequency and power sweeps. For those combinations, some timing restrictions apply. Check the SCPI command reference for further details.

Some combinations may be available only using the GUI or custom remote programming sequences, but not on the front panel.

Table 6-e: Possible combinations of internal and external modulation and the internal LF generator output.

Remarks

1. [1] Combining AM and FM/PM is available to 835/845 only.
2. [2] Enable AM first since active chirp disables live update of other settings.
3. [3] In ALC on mode.

Table 6-f: Possible combinations of internal and external modulation and sweeps.

Remarks

1. [1] AM, FM, PM modulated carrier sweep is available to 835/845 only.
2. [2] Enable modulation first since active sweep disables live update of other settings.
3. [3] In ALC on mode.

11. Remote Programming: SCPI Command Reference

The signal generator can be remotely programmed. This reference provides information for remote operation of the Berkeley Nucleonics Model 845-M using commands sent from an external controller via Ethernet, USB, or GPIB. It includes the following:

• A general description of the LAN and the bus data transfer and control functions
• A general description of how to establish connection via LAN, USB, or GPIB
• A listing of the IEEE-488 Interface Function Messages recognized by the signal generator with a description of its response
• A complete listing and description of all the Standard Commands for Programmable Instruments (SCPI) commands that can be used to control signal generator operation with examples of command usage

Programming the Instrument

All instruments described in this manual can be accessed through LAN, USB or GIPB interface. All interfaces use standard SCPI command set to pass commands to the device.

While LAN is the preferred interface for Berkeley Nucleonics instruments, GPIB is only optionally available for some models.

Ethernet LAN

All Berkeley Nucleonics signal generators are preferably remotely programmed via a 10/100Base-T LAN interface and LAN- connected computer using one of several LAN interface protocols. The LAN allows instruments to be connected together and controlled by a LAN based computer. LAN and its associated interface operations are defined in the IEEE 802.2 standard.

All instruments support the following LAN interface protocols:

• Socket based LAN. The application programming interface (API) provided with the instrument supports general programming using the LAN interface under Windows operating system.
• VXI-11.
• Telephone Network (TELNET): TELNET is used for interactive, one command at a time instrument control.
• Internet protocol optionally supported

For LAN operation, the signal generator must be connected to the LAN, and an IP address must be assigned to the signal generator either manually or by using DHCP client service. Your system administrator can tell you which method to use. Most current LAN networks use DHCP.

DHCP Configuration

If the DHCP server uses dynamic DNS to link the hostname with the assigned IP address, the hostname may be used in place of the IP address. Otherwise, the hostname is not usable.

Ethernet Interface Connection and Setup

The instrument fully supports the IEEE-802.3 standard. Most front panel functions (except power on/off) can be remotely controlled via a network server and an Ethernet connection. The instrument firmware supports the TCP/IP network protocol.

Ethernet uses a bus or star topologies where all of the interfacing devices are connected to a central cable called the bus or are connected to a hub. Ethernet uses the CSMA/CD access method to handle simultaneous transmissions over the bus. CSMA/CD stands for Carrier Sense Multiple Access/Collision Detection. This standard enables network devices to detect simultaneous data channel usage, called a collision, and provides for a contention protocol. When a network device detects a collision, the CSMA/CD standard dictates that the data will be retransmitted after waiting a random amount of time. If a second collision is detected, the data is again retransmitted after waiting twice as long. This is known as exponential back off.

The TCP/IP setup requires the following:

• IP Address. Every computer/electronic device in a TCP/IP network requires an IP address. An IP address has four numbers (each between 0 and 255) separated by periods. For example: 192.168.1.50 is a valid IP address.
• Subnet Mask. The subnet mask distinguishes the portion of the IP address that is the network ID from the portion that is the station ID. The subnet mask 255.255.0.0, when applied to the IP address given above, would identify the network ID as 192.168 and the station ID as 1.50. All stations in the same local area network should have the same network ID, but different station IDs.
• Default Gateway. A TCP/IP network can have a gateway to communicate beyond the LAN identified by the network ID. A gateway is a computer or electronic device that is connected to two different networks and can move TCP/IP data from one network to the other. A single LAN that is not connected to other LANs requires a default gateway setting of 0.0.0.0. If you have a gateway, then the default gateway would be set to the appropriate value of your gateway.
• MAC Address. A MAC address is a unique 48-bit value that identifies a network interface card to the rest of the network. Every network card has a unique MAC address permanently stored into its memory.

Interface between the instrument and other devices on the network is connected to a network via a category five (CAT-5) interface cable. This cable uses four twisted pairs of copper insulators terminated into an RJ45 connector. CAT-5 cabling is capable of supporting frequencies up to 100 MHz and data transfer speeds up to 1 Gbps, which accommodates 1000Base-T, 100Base-T, and 10Base-T networks.

Generally, a VISA I/O library (like NI-VISA™) is used on the server side to facilitate the communications. A VISA installation on the controller is a prerequisite for remote control over LAN interface. VISA is a standardized software interface library providing input and output functions to communicate with instruments. For more information about VISA refer to the VISA library supplier's documentation.

Only the IP address or the device name is required for link setup. The IP address/device name is part of the "visa resource string" used by the programs for identification and control of the instrument. The visa resource string has the form:

TCPIP::ipaddr::inst0::INSTR

ipaddr has to be replaced by the IP address or the computer name of the instrument.

For instance, if the instrument has the IP address 192.168.1.50, TCPIP::192.168.1.50::inst0::INSTR is the valid resource name. Specification of inst0 in the resource name is optional. In this example, also TCPIP::192.168.1.50::INSTR is therefore a valid resource name.

TCPIP designates the network protocol used and INSTR indicates that the VXI-11 protocol is used. If several instruments are connected to the network, each instrument has its own IP address and associated resource name. The controller identifies these instruments by means of the resource name.

Using Sockets LAN

Sockets LAN is a method used to communicate with the signal generator over the LAN interface using the Transmission Control Protocol/Internet Protocol (TCP/IP). A socket is a fundamental technology used for computer networking and allows applications to communicate using standard mechanisms built into network hardware and operating systems. The method accesses a port on the signal generator from which bidirectional communication with a network computer can be established.

Sockets LAN can be described as an internet address that combines Internet Protocol (IP) with a device port number and represents a single connection between two pieces of software. The socket can be accessed using code libraries packaged with the computer operating system. Two common versions of socket libraries are the Berkeley Sockets Library for UNIX systems and Winsock for Microsoft operating systems.

Your signal generator implements a socket Applications Programming Interface (API) that is compatible with Berkeley socket for UNIX systems and Winsock for Microsoft systems. The signal generator is also compatible with other standard sockets APIs. The signal generator can be controlled using predefined SCPI functions once the socket connection is established in your program. Socket connection is available on port 18.

Using and Configuring VXI-11 (VISA)

The signal generator supports the LAN interface protocol described in the VXI-11 standard. VXI-11 is an instrument control protocol based on Open Network Computing/Remote Procedure Call (ONC/RPC) interfaces running over TCP/IP.

A range of standard software such as NI-VISA or Agilent IO Config is available to setup the computer-signal generator interface for the VXI- 11 protocol. Please refer to the applicable software user manual and documentation for information on running the program and configuring the VXI-11 interface. The program is used to configure the LAN client. Once the computer is configured for a LAN client, you can use the VXI- 11 protocol and the VISA library to send SCPI commands to the signal generator over the LAN interface. Example programs are available on request info@berkeleynucleonics.com.

VISA is an IO library used to develop IO applications and instrument drivers that comply with industry standards. It is recommended to use the VISA library for programming the signal generator. The NI-VISA and Agilent VISA libraries are similar implementations of VISA and have the same commands, syntax, and functions.

Using Telnet LAN (Port 18)

Telnet provides a means of communicating with the signal generator over the LAN. The Telnet client, run on a LAN connected computer, will create a remote session to the signal generator. A connection, established between the computer and signal generator, generates a user interface display for the user.

Using the Telnet protocol to send commands to the signal generator is similar to communicating with the signal generator over LAN. You establish a connection with the signal generator and then send or receive information using predefined commands. Communication is interactive: one command at a time. The Telnet service is available on port 18, by default. Also, by default, signal generator does not echo commands the user type in and in some telnet program (eg: Windows TELNET) also does not print the command the user type so it is maybe necessary to send a command

SYST:COMM:SOCK:ECHO ON

for the user commands to become visible on the display

USB (USBTMC)

All instruments support the following USB interface protocols:

• USBTMC class device via VISA. USBTMC stands for USB Test & Measurement Class. USBTMC is a protocol built on top of USB that allows GPIB-like communication with USB devices. From the user's point of view, the USB device behaves just like a GPIB device. USBTMC allows instrument manufacturers to upgrade the physical layer from GPIB to USB while maintaining software compatibility with existing software such as instrument drivers and any application that uses VISA. This is also what the VXI-11 protocol provides for TCP/IP.
• USBTMC with IVI drivers. the application programming interface (API) provided with the instrument supports general programming using the USB interface under Windows operating system using the IVI drivers.

USBTMC class device requires the physical layer from GPIB to USB while maintaining software compatibility with existing software such as instrument drivers and any application that uses VISA. This is also what the VXI-11 protocol provides for TCP/IP. You can then use this resource to access the signal generator using the GPIB specific functions.

USBTMC upgrades the physical layer from GPIB to USB while maintaining software compatibility with existing software such as instrument drivers and any application that uses VISA. The new device will appear in MAX under Device and Interfaces > USB Devices. You can then use this resource name as you would use any GPIB resource.

USB-TMC Connection and Setup using VISA

USBTMC stands for USB Test & Measurement Class. USBTMC is a protocol built on top of USB that allows GPIB-like communication with USB devices. From the user's point of view, the USB device behaves just like a GPIB device. The USBTMC protocol supports service request, triggers and other GPIB specific operations.

USBTMC upgrades the physical layer from GPIB to USB while maintaining software compatibility with existing software such as instrument drivers and any application that uses VISA. This is also what the VXI-11 protocol provides for TCP/IP.

NI-VISA 3.0 or later allows you to communicate as a controller to Model 845-M devices. NI VISA is configured to detect USBTMC compliant instruments such as the Model 845-M. To use such a device, plug it in and Windows should detect the new hardware and launch the New Hardware Wizard. Instruct the wizard to search for the driver, which in this case is NI-VISA. If NI-VISA is properly installed, the device will be installed as a USB Test & Measurement Class Device. Open Measurement & Automation Explorer (MAX). The new device will appear in MAX under Device and Interfaces > USB Devices. You can then use this resource name as you would use any GPIB resource.

USB-TMC Connection and Setup using BNC API

BNC's API programming interface supports direct communication to instruments using BNC's proprietary DLL driver libraries.

Please contact BNC for more detailed documentation, programming samples, and updates on the DLL library.

GPIB Interface Connection and Setup

General GPIB information

GPIB (General Purpose Interface Bus) is an interface standard for connecting computers and peripherals, which supports the following international standards: IEEE 488.1, IEC 625, IEEE 488.2, and JIS C1901. The GPIB interface allows you to control the APPH from an external computer. The computer sends commands and instructions to the APPH and receives data sent from the APPH via GPIB.

You can connect up to 15 devices in a single GPIB system.

The length of cables to connect between devices must be 4 m or less. The total length of connecting cables in a single GPIB system must be 2 m × the number of connected devices (including the controller) or less. You cannot construct the system in which the total cable length exceeds 20 m.

You cannot connect more than four devices to an individual device must be 4 m or less. If you connect 5 or more connectors, excessive force is applied to the connector part, which may result in failure.

You can choose the device connection topology from star, linear, and combined. Loop connection is not allowed.

SCPI Commands

The Standard Commands for Programmable Instrumentation (SCPI) provides a uniform and consistent language to control programmable test and measurement devices in instrumentation systems. The SCPI Standard is built on the foundation of IEEE 488.2, Standard Codes and Formats. It requires conformance to IEEE 488.2, but is pure software standard. SCPI syntax is ASCII text, and therefore can be attached to any computer test language such as BASIC, C, or C++. It can also be used with Test Application Environments such as LabWindows/CVI, LabVIEW™, or Matlab®. SCPI is hardware independent. SCPI strings can be sent over any instrument interface. It works equally well over USB-TMC, GPIB, RS-232, VXIbus or LAN networks.

Please see the chapter 4 for detailed description of supported SCPI commands.

IEEE-488 Interface Commands

IEEE Mandated and Optional Common Commands

The required common commands are IEEE-488.2 mandated commands that are defined in the IEEE-488.2 standard and must be implemented by all SCPI compatible instruments. These commands are identified by the asterisk (*) at the beginning of the command keyword. These commands are used to control instrument status registers, status reporting, synchronization, and other common functions.

Commands declared mandatory by IEEE 488.2.

• *CLS Clear Status Command
• *ESE Standard Event Status Enable Command
• *ESE? Standard Event Status Enable Query
• *ESR? Standard Event Status Register Query
• *IDN? Identification Query
• *OPC Operation Complete Command
• *OPC? Operation Complete Query
• *RST Reset Command
• *SRE Service Request Enable Command
• *SRE? Service Request Enable Query
• *STB? Read Status Byte Query
• *TST? Self-Test Query
• *WAI Wait-to-Continue Command

Optional common commands described by IEEE 488.2

• *OPT? Option Identification Query

*CLS

The Clear Status (CLS) command clears the status byte by emptying the error queue and clearing all the event registers including the Data Questionable Event Register, the Standard Event Status Register, the Standard Operation Status Register and any other registers that are summarized in the status byte.

*ESE<data>

The Standard Event Status Enable (ESE) command sets the Standard Event Status Enable Register. The variable <data> represents the sum of the bits that will be enabled.

Range 0-255

Remarks The setting enabled by this command is not affected by signal generator preset or *RST. However, cycling the signal generator power will reset this register to zero.

*IDN?

The Identification (IDN) query outputs an identifying string. The response will show the following information: <company name>, <model number>, <serial number>, <firmware revision>

*OPC

The Operation Complete (OPC) command sets bit 0 in the Standard Event Status Register when all pending operations have finished.

The Operation Complete command causes the device to set the operation complete bit (bit 0) in the Standard Event Status Register when all pending operations have been finished.

*OPC?

The Operation Complete (OPC) query returns the ASCII character 1 in the Standard Event Status Register when all pending operations have finished.

This query stops any new commands from being processed until the current processing is complete. This command blocks the communication until all operations are complete (i.e. the timeout setting should be longer than the longest sweep).

*OPT?

The options (OPT) query returns a comma-separated list of all currently installed instrument options on the signal generator.

Common returned option strings are:

Further options are available for different signal generator model. Please refer to the Data Sheet for a complete list of options supported by a particular instrument.

*RCL<reg>

The Recall (RCL) command recalls the state from the specified memory register <reg>.

*RST

The Reset (RST) command resets most signal generator functions to factory- defined conditions.

Remarks Each command shows the [*RST] default value if the setting is affected.

*SAV <reg>

The Save (SAV) command saves signal generator settings to the specified memory register <reg>.

Remarks The save function does not save all signal generator settings. Refer to the User's Guide for more information on the save function.

*SRE<data>

The Service Request Enable (SRE) command sets the value of the Service Request Enable Register. The variable <data> is the decimal sum of the bits that will be enabled. Bit 6 (value 64) is ignored and cannot be set by this command.

Range 0-255

The setting enabled by this command is not affected by signal generator preset or *RST. However, cycling the signal generator power will reset it to zero.

*SRE?

The Service Request Enable (SRE) query returns the value of the Service Request Enable Register.

Range 0-63 & 128-191

*STB?

The Read Status Byte (STB) query returns the value of the status byte including the master summary status (MSS) bit.

Range 0-255

*TRG

The Trigger (TRG) command triggers the device if LAN is the selected trigger source, otherwise, *TRG is ignored.

*TST?

The Self-Test (TST) query initiates the internal self- test and returns one of the following results:

• 0 This shows that all tests passed.
• 1 This shows that one or more tests failed.

*WAI

The Wait- to- Continue (WAI) command causes the signal generator to wait until all pending commands are completed, before executing any other commands.

SCPI Commands

This chapter provides an introduction to SCPI programming that includes descriptions of the command types, hierarchical command structure, data parameters, and notational conventions. Information on Model 845-M status system and trigger system programming is also provided.

Introduction

Standard Commands for Programmable Instruments (SCPI) is the new instrument command language for controlling instruments that goes beyond IEEE 488.2 to address a wide variety of instrument functions in a standard manner. SCPI promotes consistency, from the remote programming standpoint, between instruments of the same class and between instruments with the same functional capability. For a given measurement function such as frequency or voltage, SCPI defines the specific command set that is available for that function. Thus, two oscilloscopes made by different manufacturers could be used to make frequency measurements in the same way. It is also possible for a SCPI counter to make a frequency measurement using the same commands as an oscilloscope. SCPI commands are easy to learn, self-explanatory and account for both novice and expert programmer's usage. Once familiar with the organization and structure of SCPI, considerable efficiency gains can be achieved during control program development, independent of the control program language selected.

A key to consistent programming is the reduction of multiple ways to control similar instrument functions. The philosophy of SCPI is for the same instrument functions to be controlled by the same SCPI commands. To simplify learning, SCPI uses industry-standard names and terms that are manufacturer and customer supported.

The advantage of SCPI for the ATE system programmer is reducing the time learning how to program new SCPI instruments after programming their first SCPI instrument.

Programmers who use programming languages such as BASIC, C, FORTRAN, etc., to send instrument commands to instruments will benefit from SCPI. Also, programmers who implement instrument device drivers for ATE program generators and/or software instrument front panels will benefit by SCPI's advantages. SCPI defines instrument commands, parameters, data, and status. It is not an application package, programming language or software intended for instrument front panel control.

SCPI is designed to be layered on top of the hardware-independent portion of IEEE 488.2.

SCPI Command Types

SCPI commands, which are also referred to as SCPI instructions, are messages to the instrument to perform specific tasks. The Model 845-M command set includes:

• "Common" commands (IEEE488.2 mandated commands)
• SCPI required commands
• SCPI optional commands (per SCPI 1999.0)
• SCPI compliant commands that are unique to the Model 845-M. Not all of the commands supported by the instrument are taken from the SCPI standard; however, their syntax follows SCPI rules.

SCPI Command Syntax

Typical SCPI commands consist of one or more keywords, parameters, and punctuation. SCPI command keywords can be a mixture of upper and lower case characters. Except for common commands, each keyword has a long and a short form. In this manual, the long form is presented with the short form in upper case and the remainder in lower case. Unrecognized versions of long form or short form commands, or improper syntax, will generate an error.

Structure of a Command Line

A command line may consist of one or several commands. It is terminated by an EOI together with the last data byte.

Several commands in a command line must be separated by a semicolon ";". If the next command belongs to a different command system, the semicolon is followed by a colon. A colon ":" at the beginning of a command marks the root node of the command tree.

If the successive commands belong to the same system, having one or several levels in common, the command line can be abbreviated. To this end, the second command after the semicolon starts with the level that lies below the common levels. The colon following the semicolon must be omitted in this case.

Responses to Queries

A query is defined for each setting command unless explicitly specified otherwise. It is formed by adding a question mark to the associated setting command. According to SCPI, the responses to queries are partly subject to stricter rules than in standard IEEE 488.2.

Parameters

Most commands require a parameter to be specified. The parameters must be separated from the header by a "white space". Permissible parameters are numerical values, Boolean parameters, text, character strings and block data. The type of parameter required for the respective command and the permissible range of values are specified in the command description.

• Numerical values. Numerical values can be entered in any form, i.e. with sign, decimal point and exponent. Values exceeding the resolution of the instrument are rounded up or down. The mantissa may comprise up to 255 characters, the values must be in the value range −9.9E37 to 9.9E37. The exponent is introduced by an "E" or "e". Entry of the exponent alone is not allowed.
• Units. In the case of physical quantities, the unit can be entered. Permissible unit prefixes are G (giga), MA (mega), MHZ are also permissible), K (kilo), M (milli), U (micro) and N (nano). If the unit is missing, the basic unit is used.
• Boolean Parameters. Boolean parameters represent two states. The ON state (logically true) is represented by ON or a numerical value unequal to 0. The OFF state (logically false) is represented by OFF or the numerical value 0. ON or OFF is returned by a query.

Hierarchical Command Structure

All SCPI commands, except the common commands, are organized in a hierarchical structure similar to the inverted tree file structure used in most computers. The SCPI standard refers to this structure as "the Command Tree." The command keywords that correspond to the major instrument control functions are located at the top of the command tree. The command keywords for the Model 845-M SCPI command set are shown below.

• :ABORt
• :DIAGnostic
• :DISPlay
• :INITiate
• :OUTput
• :SOURce
• :STATus
• :SYSTem
• :TRIGger
• :UNIT

All Model 845-M SCPI commands, except the :ABORt command, have one or more subcommands (keywords) associated with them to further define the instrument function to be controlled. The subcommand keywords may also have one or more associated subcommands (keywords). Each subcommand level adds another layer to the command tree. The command keyword and its associated subcommand keywords form a portion of the command tree called a command subsystem.

Status System Programming

The Model 845-M implements the status byte register, the Service Request Enable Register, the Standard Event Status Register, and the Standard Event Status Enable Register.

The Model 845-M status system consists of the following SCPI-defined status reporting structures:

• The Instrument Summary Status Byte
• The Standard Event Status Group
• The Operation Status Group
• The Questionable Status Group

The following paragraphs describe the registers that make up a status group and explain the status information that each status group provides.

Status Registers

In general, a status group consists of a condition register, a transition filter, an event register, and an enable register. Each component is briefly described in the following paragraphs.

Condition Register

The condition register is continuously updated to reflect the current status of the Model 845-M. There is no latching or buffering for this register, it is updated in real time. Reading the contents of a condition register does not change its contents.

Transition Filter

The transition filter is a special register that specifies which types of bit state changes in the condition register will set corresponding bits in the event register. Negative transition filters (NTR) are used to detect condition changes from True (1) to False (0); positive transition filters (PTR) are used to detect condition changes from False (0) to True (1). Setting both positive and negative filters True (1) allows an event to be reported each time the value changes. Resetting both filters False (0) disables event reporting. The action of these filters is paralleled by a query of a *CLS command result.

Event Register

The event register latches transition events from the condition register as specified by the transition filter. Bits in the event register are latched, and once set they remain set until cleared by a query or a *CLS command. Event registers are read only.

Enable Register

The enable register specifies the bits in the event register that can produce a summary bit. The Model 845-M logically ANDs corresponding bits in the event and enable registers, and ORs all the resulting bits to obtain a summary bit. Summary bits are recorded in the Summary Status Byte. Enable registers are read-write. Querying an enable register does not affect it. The command :STATus:PRESet sets the Operation Status Enable register and the Questionable Status Enable register to all 0's.

Status Group Reporting

The state of certain Model 845-M hardware and operational events and conditions can be determined by programming the status system. Three lower status groups provide status information to the Summary Status Byte group. The Summary Status Byte group is used to determine the general nature of an event or condition and the other status groups are used to determine the specific nature of the event or condition.

Summary Status Byte Group

The Summary Status Byte group, consisting of the Summary Status Byte Enable register and the Summary Status Byte, is used to determine the general nature of an Model 845-M event or condition. The bits in the Summary Status Byte provide the following:

Operation Status Group

The Operation Status group, consisting of the Operation Condition register, the Operation Positive Transition register, the Operation Negative Transition register, the Operation Event register and the Operation Event Enable register.

Standard Event Status Group

The Standard Event Status group, consisting of the Standard Event Status register (an Event register) and the Standard Event Status Enable register, is used to determine the specific event that set bit 5 of the Summary Status Byte.

The bits in the Standard Event Status register provide the following:

Standard Event Status Enable register (ESE commands)

Operation Status Group

The Operation Status group, consisting of the Operation Condition register, the Operation Positive Transition register, the Operation Negative Transition register, the Operation Event register, and the Operation Event Enable register, is used to determine the specific condition that set bit 7 in the Summary Status Byte.

Related commands are covered by the :STATus Subsystem chapter.

The bits in the Operation Event register provide the following:

Questionable Status Group

The Questionable Status group, consisting of the Questionable Condition register, the Questionable Positive Transition register, the Questionable Negative Transition register, the Questionable Event register, and the Questionable Event Enable register, is used to determine the specific condition that set bit 3 in the Summary Status Byte.

Related commands are covered by the :STATus Subsystem chapter.

The bits in the Questionable Status register provide the following:

:ABORt Subsystem

The :ABORt command is a single command subsystem. There are no subcommands or associated data parameters, as shown below. The :ABORt command, along with the :TRIGger and :INITiate commands, comprise the Trigger group of commands.

:ABORt

This command causes the List or Step sweep in progress to abort. Even if INIT:CONT[:ALL] is set to ON, the sweep will not immediately re-initiate.

:DISPlay Subsystem

The :DISPlay subsystem controls the display of the front panel data display.

:DISPlay[:WINDow]:TEXT:[STATe] ON|OFF|1|0

:DISPlay:WINDow:TEST ON|OFF|1|0
:DISPlay[:WINDow]:TEXT:[STATe] ON|OFF|1|0
:DISPlay[:WINDow]:TEXT:STATe?

Turns on/off the parameter display of the Model 845-M front panel data display.

:DISPlay:REMote ON|OFF|1|0

:DISPlay:REMote ON|OFF|1|0
:DISPlay:REMote?

Turns on/off the display update of the Model 845-M front panel data display.

:INITiate Subsystem

The :INITiate subsystem controls the state of the Model 845-M trigger system. The subsystem commands and parameters are described below. The :INITiate commands, along with the :ABORt and :TRIGger commands, comprise the Trigger Group of commands.

:INITiate[:IMMediate]

Sets Model 845-M trigger to the armed state.

:INITiate:CONTinuous ON|OFF|1|0

Continuously rearms the Model 845-M trigger system after completion of a triggered sweep.

:OUTPut Subsystem

[:STATe] ON|OFF|1|0

:OUTPut[:STATe] ON|OFF|1|0

Turns Model 845-M RF output power on/off.

:BLANking[:STATe] ON|OFF|1|0

:OUTPut:BLANking[:STATe] ON|OFF|1|0
:OUTPut:BLANking[:STATe]?

ON causes the RF output to be turned off (blanked) during frequency changes. OFF leaves RF output turned on (unblanked).

[SOURce]:FREQuency Subsystem

:FREQuency[:CW]

[SOURce]:FREQuency[:CW] <value><unit>
[SOURce]:FREQuency[:CW]?

This command sets the signal generator output frequency for the CW frequency mode.

*RST 100 MHz

Range Please refer to the Data Sheet.

:FREQuency:MODE

[SOURce]:FREQuency:MODE FIX|CW|SWEep|LIST
[SOURce]:FREQuency:MODE?

This command sets the frequency mode of the signal generator to CW or swept.

• FIX | CW. Stops a frequency sweep.
• SWEep or LIST. This choice selects the swept frequency mode. If sweep triggering is set to immediate along with continuous sweep mode, executing the command starts the LIST or SWEep frequency sweep. In SWEep mode, frequency will be determined by programmed values for the :STARt and :STOP :FREQuency subsystem commands. In LIST mode, frequency is determined by programmed values for :LIST:FREQuency.

:FREQuency:STARt

[SOURce]:FREQuency:STARt <value><unit>
[SOURce]:FREQuency:STARt?

This command sets the first frequency point in a step sweep.

*RST The preset value is 1 GHz. Please refer to the Data Sheet.

Range Please refer to the Data Sheet.

:FREQuency:STOP

[SOURce]:FREQuency:STOP <value><unit>
[SOURce]:FREQuency:STOP?

This command sets the last frequency point in a step sweep.

*RST The preset value is 2 GHz.

Range Please refer to the Data Sheet.

[SOURce]:FREQuency:STEP

[SOURce]:FREQuency:STEP[:LINear] <value><unit>

This command sets the step size for a linear step sweep.

[SOURce]:FREQuency:STEP:LOGarithmic

[SOURce]:FREQuency:STEP:LOGarithmic <value>

This command sets the step size for a logarithmic step sweep.

[SOURce]:PHASe Subsystem

:PHASe:REFerence

[SOURce]:PHASe:REFerence

This command sets the current output phase as a zero reference. Subsequent phase adjustments are set relative to the new reference.

:PHASe[:ADJust]

[SOURce]:PHASe[:ADJust] <value><unit>
[SOURce]:PHASe[:ADJust]?

This command adjusts the phase of the signal. The query will only return values in radians.

*RST The preset value is 0.

[SOURce]:POWer Subsystem

[:LEVel][:IMMediate][:AMPLitude]

[SOURce]:POWer[:LEVel][:IMMediate][:AMPLitude] <value><unit>
[SOURce]:POWer[:LEVel][:IMMediate][:AMPLitude]?

This command sets the RF output power.

:MODE

[SOURce]:POWer:MODE CW|LIST|SWEep
[SOURce]:POWer:MODE?

This command sets the signal generator power mode to fixed or swept.

• FIX. This choice stops a power sweep, allowing the signal generator to operate at a fixed power level. Refer to [:LEVel][:IMMediate][:AMPLitude] command for setting the output power level.
• LIST or SWEep. This choice selects the swept power mode. If sweep triggering is set to immediate along with continuous sweep mode, executing the command starts the LIST or STEP power sweep.

:STARt

[SOURce]:POWer:STARt <value><unit>
[SOURce]:POWer:STARt?

This command sets the first amplitude point in a step sweep.

Range

:STOP

[SOURce]:POWer:STOP <value><unit>
[SOURce]:POWer:STOP?

This command sets the last amplitude point in a step sweep.

Range

:ALC

[SOURce]:POWer:ALC ON|OFF|1|0
[SOURce]:POWer:ALC?

This command turns the automatic power level control on and off.

*RST The preset value is 1.

:ALC:HOLD

[SOURce]:POWer:ALC:HOLD ON|OFF|1|0
[SOURce]:POWer:ALC?

(Devices with option PE only)

This command sets the automatic level control into hold mode. The amplitude level control loop is open.

*RST The preset value is 0.

:ATTenuation

[SOURce]:POWer:ATTenuation <value>
[SOURce]:POWer:ATTenuation?

(Devices with option PE only)

This command sets the power range extension attenuator. This command will also turn off automatic attenuation setting. Refer to [SOURce]:POWer:ATTenuation:AUTO OFF for details. Attenuator input RF power shall be -30 to +10 dBm, e.g. using a [SOURce]:POWer:ATTenuation value of 50 dB, the output RF power range is -80 to -40 dBm.

*RST The preset value is 0.

:ATTenuation:AUTO

[SOURce]:POWer:ATTenuation:AUTO ON|OFF|1|0
[SOURce]:POWer:ATTenuation:AUTO?

(Devices with option PE only)

This command turns the power range extension on or off. Turning it off allows fast power sweeps for devices featuring an extended output power range.

*RST The preset value is 0.

:ATTenuation:LIST?

[SOURce]:POWer:ATTenuation:AUTO?

(Devices with option PE only)

This query returns a comma-separated list of available attenuation settings. These can be set using the [SOURce]:POWer:ATTenuation command. Available settings are:

• 0, 35, 70 dB for option PE2A
• 0, 10, 20, ..., 70 dB for option PE3
• 0, 10, 20, ..., 110 dB for option PE4
• 0, 35, 70, 105 dB for option PE5

[SOURce]:ROSCillator Subsystem

:EXTernal:FREQuency

[SOURce]:ROSCillator:EXTernal:FREQuency <val>
[SOURce]:ROSCillator:EXTernal:FREQuency?

This command conveys the expected reference frequency value of an externally applied reference to the signal generator. The variable <val> is expressed in units of MHz.

*RST 10 MHz

Range 1 to 250 MHz

:LOCKed?

[SOURce]:ROSCillator:LOCKed?

This command queries if the synthesizer is locked to the externally applied reference.

:OUTPut:STATe

[SOURce]:ROSCillator:OUTPut:STATe ON|OFF|1|0
[SOURce]:ROSCillator:OUTPut:STATe?

This command enables or disables the 10 MHz frequency reference output.

*RST OFF

:SOURce

[SOURce]:ROSCillator:SOURce INT | EXT

This command selects either an internal or external reference for the waveform clock.

*RST INT

[SOURce]:LIST Subsystem

:LIST:DIRection

[SOURce]:LIST:DIRection UP|DOWN|RANDom
[SOURce]:LIST:DIRection?

This command sets the direction of a list or step sweep.

• UP. This choice enables a sweep in an ascending order: first to last point for a list sweep; start to stop for a step sweep.
• DOWN. This choice reverses the direction of the sweep.

*RST UP

:LIST:DWELl

[SOURce]:LIST:DWELl <value>{,<value>}
[SOURce]:LIST:DWELl:POINts?

This command sets the dwell time for the current list sweep points. Dwell time is used when IMMediate is the trigger source. The dwell time is the amount of time the sweep is guaranteed to pause after setting the frequency and/or power for the current point.

The setting enabled by this command is not affected by signal generator power-on, preset, or *RST. The variable <value> is expressed in units of seconds.

:LIST:DELay

[SOURce]:LIST:DELay <value>{,<value>}
[SOURce]:LIST:DELay:POINts?

This command sets the off time for the current list sweep points. Off time is used when IMMediate is the trigger source. The off time is the amount of time the output is guaranteed to be blanked after setting the frequency and/or power for the current point to suppress output transients during a frequency change.

The setting enabled by this command is not affected by signal generator power-on, preset, or *RST. The variable <value> is expressed in units of seconds.

:LIST:DELay:AUTO

[SOURce]:LIST:DELay:AUTO ON|OFF|1|0

This command enables the automatic blanking of the output during transients between two frequency steps.

*RST ON

:LIST:FREQuency:POINts

[SOURce]:LIST:POINts?

This command queries the signal generator for the number of frequency points in the current list sweep file.

:LIST:FREQuency

[SOURce]:LIST:FREQuency <value>{,<value>}
[SOURce]:LIST:FREQuency?

This command sets the frequency values for the current list sweep points. The maximum number of list sweep points is 3-501. The variable <value> is expressed in units of Hertz.

The setting enabled by this command is not affected by signal generator power-on, preset, or *RST.

Range Please consult the Data Sheet.

:LIST:MANual

[SOURce]:LIST:MANual <value>|UP|DOWN
[SOURce]:LIST:MANual?

This command sets a list or step sweep point as the current sweep point controlling the frequency and power output. If list or step mode is controlling frequency or power, or both, then the indexed point in the respective list(s) will be used.

Entering a value with this command will have no effect, unless MANual is the selected mode. Refer to :LIST:MODE command for setting the proper mode.

If the point selected is beyond the length of the longest enabled list, then the point will be set to the maximum possible point, and an error will be generated.

Range 1-3-501

:LIST:MODE

[SOURce]:LIST:MODE AUTO|MANual
[SOURce]:LIST:MODE?

This command sets the operating mode for the current list or step sweep.

• AUTO. This choice enables the selected sweep type to perform a sweep of all points.
• MANual. This choice enables you to select a single sweep point. The selected point controls the frequency and/or amplitude according to the sweep type. Refer to :LIST:MANual command for selecting a sweep point.

*RST AUTO

:LIST:POWer

[SOURce]:LIST:POWer <value>{,<value>}
[SOURce]:LIST:POWer?

This command sets the amplitude for the current list sweep points.

:LIST:POWer:POINts

[SOURce]:LIST:POWer:POINts?

This command queries the number of power points in the current list sweep file.

:LIST:COUNt

[SOURce]:LIST:COUNt <value>
[SOURce]:LIST:COUNt?

This command sets the number of consecutive times the list is executed on each sweep start. The variable <value> is 1 to 65535 or INFinity.

:LIST:PROGress

[SOURce]:LIST:PROGress?

This query returns the progress of an active list sweep, 0.0-1.0.

[SOURce]:LFOutput Subsystem

:LFOutput:AMPLitude

[SOURce]:LFOutput:AMPLitude <value>
[SOURce]:LFOutput:AMPLitude?

This command sets the low frequency generator amplitude. This setting does only take effect if :LFOutput:SOURce is set to LFGenerator and LFOutput:SHAPe is either set to SINE or TRIangle. Using any other setting, the output amplitude is fixed 2.5 V. The variable <value> is expressed in units of Volt.

Range 0-2.5

*RST 1

:LFOutput:FREQuency

[SOURce]:LFOutput:FREQuency <value>
[SOURce]:LFOutput:FREQuency?

This command sets the low frequency generator frequency. This setting does only take effect if :LFOutput:SOURce is set to LFGenerator. The variable <value> is expressed in units of Hertz.

Range 10-5000000

*RST 400

:LFOutput:STATe

[SOURce]:LFOutput:STATe ON|OFF|1|0
[SOURce]:LFOutput:STATe?

This command sets the function output / low frequency generator state.

*RST OFF

:LFOutput:SHAPe

[SOURce]:LFOutput:SHAPe SINE|TRIangle|SQUare
[SOURce]:LFOutput:SHAPe?

This command sets the low frequency generator waveform. This setting does only take effect if :LFOutput:SOURce is set to LFGenerator.

• SINE. Sine wave output, amplitude is selectable by the :LFOutput:AMPLitude setting.
• TRIangle. Triangle wave output, amplitude is selectable by the :LFOutput:AMPLitude setting.
• SQUare. Square wave output, amplitude is fixed 2.5 V.

*RST SINE

:LFOutput:SOURce

[SOURce]:LFOutput:SOURce LFGenerator|PULM|TRIGger
[SOURce]:LFOutput:SOURce?

This command sets the low frequency generator waveform. This setting does only take effect if :LFOutput:SOURce is set to LFGenerator.

• LFGenerator. This selects the low frequency generator as the function output signal.
• PULM. This selects the pulse modulation video out as the function output signal.
• TRIGger. This selects the trigger as the function output signal.

*RST LFG

[SOURce]:SWEep Subsystem

:DIRection UP|DOWN|RANDom

[SOURce]:SWEep:DIRection UP | DOWN | RANDom

:SWEep:POINts

[SOURce]:SWEep:POINts <value>
[SOURce]:SWEep:POINts?

This command defines the number of step sweep points.

*RST 101

Range 2-65535

:SWEep:DWELl

[SOURce]:SWEep:DWELl <value>
[SOURce]:SWEep:DWELl?

This command sets the dwell time for the current step sweep points. Dwell time is used when IMMediate is the trigger source. The dwell time is the amount of time the sweep is guaranteed to pause after setting the frequency and/or power for the current point.

The setting enabled by this command is not affected by signal generator power-on, preset, or *RST. The variable <value> is expressed in units of seconds (default: 1000 ps).

:SWEep:DELay

[SOURce]:SWEep:DELay <value>
[SOURce]:SWEep:DELay?

This command sets the off time for the current step sweep points. Off time is used when IMMediate is the trigger source. The off time is the amount of time the sweep is guaranteed to pause after setting the frequency and/or power for the current point.

The setting enabled by this command is not affected by signal generator power-on, preset, or *RST. The variable <value> is expressed in units of seconds (default: 300 ps).

:SWEep:PROGress

[SOURce]:SWEep:PROGress?

This query returns the progress of an active sweep, 0.0-1.0.

:SWEep:SPACing

[SOURce]:SWEep:SPACing LINear | LOGarithmic
[SOURce]:SWEep:SPACing?

This command enables the signal generator linear or logarithmic sweep modes. These commands require the signal generator to be in step mode. The instrument uses the specified start frequency, stop frequency, and number of points for both linear and log sweeps.

*RST LIN

:STARt

[SOURce]:POWer:STARt <value><unit>
[SOURce]:POWer:STARt?

This command sets the first amplitude point in a step sweep.

*RST ?

Range Refer to [:LEVel][:IMMediate][:AMPLitude] command for the output power ranges.

:STOP

[SOURce]:POWer:STOP <value><unit>
[SOURce]:POWer:STOP?

This command sets the last amplitude point in a step sweep.

*RST ?

Range Refer to [:LEVel][:IMMediate][:AMPLitude] command for the output power ranges.

[SOURce]:AM Subsystem (Amplitude Modulation)

:AM:DEPTh

[SOURce]:AM[:DEPTh]: <value>
[SOURce]:AM[:DEPTh]:?

This command sets the amplitude modulation depth 0...1.

*RST 0.8

Range 0-0.99

:AM:INT:FREQuency

[SOURce]:AM:INTernal:FREQuency <value><unit>|UP|DOWN
[SOURce]:AM:INTernal:FREQuency?

This command sets the internal amplitude modulation rate.

*RST 400 Hz

Range 10 Hz to 50,000 Hz

The RF carrier is modulated when you have set the signal generator's AM modulation state to ON. Whenever amplitude modulation is enabled, the AM on is in the display.

[SOURce]:FM Subsystem (Frequency Modulation)

:FM:DEViation

[SOURce]:FM:DEViation <value>
[SOURce]:FM:DEViation?

This command sets the frequency modulation deviation. This setting will be used if :FM:SOURce is set to LFGenerator. The variable <value> is expressed in units of Hertz.

*RST 10000

:FM:SENSitivity

[SOURce]:FM:SENSitivity <value>
[SOURce]:FM:SENSitivity?

This command sets the frequency modulation deviation per one volt peak amplitude signal input. This setting will be used if :FM:SOURce is set to EXTernal. The variable <value> is expressed in units of Hertz per Volt.

*RST 10000

:FM:INT:FREQuency

[SOURce]:FM:INT:FREQuency <value>
[SOURce]:FM:INT:FREQuency?

This command sets the frequency modulation rate in Hz. This setting will be used if :FM:SOURce is set to INTernal. The variable <value> is expressed in Hertz.

*RST

:FM:SOURce

[SOURce]:FM:SOURce EXTernal | INTernal
[SOURce]:FM:SOURce?

This command selects the FM modulation signal source. If INTernal is selected, an internal modulation source is applied. If EXTernal is selected, the device's ΦM input (at the rear panel) is activated.

*RST EXT

:FM:STATe

[SOURce]:FM:STATe ON|OFF|1|0
[SOURce]:FM:STATe?

This command turns the frequency modulation on or off.

*RST OFF

:FM:COUPling

[SOURce:]FM:COUPling DC | AC
[SOURce:]FM:COUPling?

This command selects the signal coupling for the external FM modulation.

*RST AC

[SOURce]:PM Subsystem (Phase Modulation)

:PM:DEViation

[SOURce]:PM:DEViation <value>
[SOURce]:PM:DEViation?

This command sets the phase modulation deviation. This setting will be used if :PM:SOURce is set to LFGenerator. The variable <value> is expressed in units of radians.

*RST 1

:PM:SENSitivity

[SOURce]:PM:SENSitivity <value>
[SOURce]:PM:SENSitivity?

This command sets the phase modulation deviation per one volt peak amplitude signal input. This setting will be used if :PM:SOURce is set to EXTernal. The variable <value> is expressed in units of radians per Volt.

*RST 1

:PM:SOURce

[SOURce]:PM:SOURce EXTernal | INTernal
[SOURce]:PM:SOURce?

This command selects the PM modulation signal source. If INTernal is selected, an internal modulation source is applied. If EXTernal is selected, the device's ΦM input (at the rear panel) is activated.

*RST EXT

:PM:STATe

[SOURce]:PM:STATe ON|OFF|1|0
[SOURce]:PM:STATe?

This command turns the phase modulation on or off.

*RST OFF

[SOURce]:PULM Subsystem (Pulse Modulation)

This additional functionality provides pulse modulation of the RF output signal delivered to the load by an internal or external modulation signal. The INTernal selection accesses the internally generated modulation input while EXTernal selects the external pulse (rear panel connector) input.

:PULM:POLarity

[SOURce]:PULM:POLarity NORMal|INVerted
[SOURce]:PULM:POLarity?

This command selects the polarity of the pulse modulation, regardless if the internal or external modulation source is used.

*RST Normal

:PULM:INTernal:FREQuency

[SOURce]:PULM:INTernal:FREQuency <frequency>
[SOURce]:PULM:INTernal:FREQuency?

This command sets the pulse rate for the internally-generated square wave using the variable <frequency>.

*RST 400 Hz

Range INT: 0.1 Hz to 100 kHz, EXT: 0.1 Hz to 10 MHz

:PULM:INTernal:PERiod

[SOURce]:PULM:INTernal:PERiod <period>
[SOURce]:PULM:INTernal:PERiod?

This command sets the pulse period for the internally generated pulse modulation using the variables <value>. If the entered value for the pulse period is equal to or less than the value for the pulse width, the pulse width changes to a value that is less than the pulse period.

*RST 2.5 ms

Range 200 ns to 10 s

:PULM:INTernal:PWIDth

[SOURce]:PULM:INTernal:PWIDth <num>
[SOURce]:PULM:INTernal:PWIDth?

This command sets the pulse width for the internally generated pulse signal. This command sets the pulse width for the internally-generated pulse modulation using the variable <num>. If the entered value for the pulse width is equal to or greater than the value for the pulse period, the pulse width changes to a value that is less than the pulse period.

*RST 1.25 ms

Range 50 ns to PERiod

:PULM:SOURce

[SOURce]:PULM:SOURce INTernal|EXTernal
[SOURce]:PULM:SOURce?

*RST INT

:PULM:STATe

[SOURce]:PULM:STATe ON|OFF|1|0
[SOURce]:PULM:STATe?

This command enables or disables pulse modulation for the selected path.

*RST 0

:PULM:MODE

[SOURce]:PULM:MODE FIXed | LIST
[SOURce]:PULM:MODE?

This command sets the modulation mode. With "FIXed", the normal ON/OFF modulation can be performed. With LIST, an arbitrary bit pattern can be loaded that will be used to modulate the carrier. LIST mode is available with pulse train option.

*RST FIXed

:TRIGger Subsystem

Triggers control the playback by telling the Model 845-M when to play the signal. Depending on the trigger settings for the Model 845-M, the waveform playback can occur once, continuously, or the 845-M may start and stop playing the waveform repeatedly (GATE mode). A trigger signal comprises both positive and negative signal transitions (states), which are also called high and low periods. You can configure the 845-M to trigger on either state of the trigger signal. It is common to have multiple triggers, also referred to as trigger occurrences or events, occur when the signal generator requires only a single trigger. In this situation, the Model 845-M recognizes the first trigger and ignores the rest.

When you select a trigger mode, you may lose the signal from the RF output until you trigger the waveform.

There are four parts to configuring the trigger:

1. Choosing the trigger type which controls the waveform's transmission.
   • NORMal. Trigger edge initiates/stops sweeps.
   • GATE. Trigger level starts/stops sweep.
2. Setting the waveform's response to triggers:
   • CONTinuous. Repeatedly accepts trigger events.
   • SINGle. Uses only one trigger event.
3. Selecting the trigger source which determines how the Model 845-M receives its trigger signal, internally or externally. The GATE choice requires an external trigger.
4. Setting the trigger polarity when using an external source.

:TRIGger:TYPE

TRIGger[:SEQuence]:TYPE NORMal | GATE | POINT
TRIGger[:SEQuence]:TYPE?

This command sets the trigger type that controls the waveform's playback. The following list describes the trigger type command choices:

• NORMal. Upon triggering, the waveform sequence plays according to settings defined by :INITiate:CONTinuous (only once or repeatedly).
• GATE. An external trigger signal repeatedly starts and stops the waveform's playback. The time duration for playback depends on the duty period of the trigger signal and the gate polarity selection. The waveform plays during the inactive state and stops during the active polarity selection state. The active state can be set high or low. The gate mode works only with an external trigger source.
• POINt. Upon triggering, only a single point of the sweep (list) is played.

*RST NORM

:TRIGger[:SEQuence]:TYPE:GATE

TRIGger[:SEQuence]:TYPE:GATE LOW|HIGH
TRIGger[:SEQuence]:TYPE:GATE?

This command selects the active state (gate polarity) of the gate while using the gating trigger mode. The LOW and HIGH selections correspond to the low and high states of an external trigger signal. For example, when you select HIGH, the active state occurs during the high of the trigger signal. When the active state occurs, the Model 845-M starts the waveform playback at the last played sample point, then stops the playback at the next sample point when the inactive state occurs.

• LOW. The waveform playback starts when the trigger signal goes low (active state) and stops when the trigger signal goes high (inactive state).
• HIGH. The waveform playback starts when the trigger signal goes high (active state) and stops when the trigger signal goes low (inactive state).

*RST HIGH

:TRIGger[:SEQuence]:SOURce

TRIGger[:SEQuence]:SOURce IMMediate|KEY|EXTernal|BUS
TRIGger[:SEQuence]:SOURce?

This command sets the trigger source.

• IMMediate. No waiting for a trigger event occurs.
• KEY. This choice enables manual triggering by pressing the front-panel RF on/off.
• EXTernal. This choice enables the triggering of a sweep event by an externally applied signal at the MOD IN connector.
• BUS. This choice enables triggering over the LAN using the *TRG or GET commands.

*RST IMM

:TRIGger[:SEQuence]:DELay

TRIGger[:SEQuence]:DELay <value>
TRIGger[:SEQuence]:DELay?

This command sets the amount of time to delay the Model 845-M response to an external trigger. The delay is a path (time) delay between when the Model 845-M receives the trigger and when it responds to the trigger. The delay does not occur until you turn it on. You can set the delay value either before or after turning it on.

:TRIGger[SEQuence]:SLOPe

TRIGger[:SEQuence]:SLOPe POSitive|NEGative
TRIGger[:SEQuence]:EXTernal:SLOPe?

This command sets the polarity for an external trigger signal while using the continuous, single triggering mode. The POSitive and NEGative selections correspond to the high (positive) and low (negative) states of the external trigger signal. For example, when you select POSitive, the waveform responds (plays) during the high state of the trigger signal. When the Model 845-M receives multiple trigger occurrences when only one is required, the signal generator uses the first trigger and ignores the rest.

*RST POS

:TRIGGer[:SEQuence]:RETRigger

TRIGGer[:SEQuence]:RETRigger ON|OFF|IMMediate
TRIGGer[:SEQuence]:RETRigger?

This command enables or disables the ARB retriggering mode; the retrigger mode controls how the retriggering function performs while a waveform is playing.

• ON (1). This choice specifies that if a trigger occurs while a waveform is playing, the waveform will retrigger at the end of the current waveform sequence and play once more.
• OFF (0). This choice specifies that if a trigger occurs while a waveform is playing, the trigger will be ignored.
• IMMediate. This choice specifies that if a trigger occurs while a waveform is playing, the waveform will reset and replay from the start immediately upon receiving a trigger.

*RST ON

:TRIGger[:SEQuence]:ECOunt

TRIGGer[:SEQuence]:ECOunt <value>
TRIGGer[:SEQuence]:ECOunt?

This command sets a modulo on consecutive trigger events. Setting the value to N means that only every Nth trigger event will be considered. Setting it to one means it will use every trigger event that does not occur during a running sweep.

*RST 1

Range 1 to 255

:TRIGger[:SEQuence]:OUTPut:POLarity

TRIGGer[:SEQuence]:OUTPut:POLarity NORMal|INVerted
TRIGGer[:SEQuence]:OUTPut:POLarity?

This command sets the trigger output signal polarity. Note that the trigger output must be enabled by sending the [:SOURce]:LFOutput:SOURce TRIGger command.

*RST NORM

:TRIGger[:SEQuence]:OUTPut:MODE

TRIGGer[:SEQuence]:OUTPut:MODE NORMal|GATE|POINt

This command sets the trigger output signal mode.

• NORMal. The trigger output signal is pulsed once whenever playing a waveform sequence is triggered.
• GATE. The trigger output signal is set when playing a waveform sequence is triggered, and reset when playing stops.
• POINT. The trigger output signal is pulsed for each point of the sweep (list) playing.

Note that the trigger output must be enabled by sending the [:SOURce]:LFOutput:SOURce TRIGger command.

*RST NORM

:STATus Subsystem

This subsystem controls the status-reporting structures.

:OPERation?

:STATus:OPERation[:EVENt]?

This query returns the contents of the operation status event register and clears it.

:OPERation:CONDition?

:STATus:OPERation:CONDition?

This query returns the contents of the operation status condition register.

:OPERation:ENABle

:STATus:OPERation:ENABle

This command sets the enable mask of the operation status event register.

:OPERation:PTR

:STATus:OPERation:PTR

This command sets the positive transition filter of the operation status event register.

:OPERation:NTR

:STATus:OPERation:NTR

This command sets the negative transition filter of the operation status event register.

:PRESet

:STATus:PRESet

Disables all status events, clears all negative transition filters and sets all positive transition filters.

:QUEStionable?

:STATus:QUEStionable [:EVENt]?

This query returns the contents of the questionable status event register and clears it.

:QUEStionable:CONDition?

:STATus:QUEStionable:CONDition?

This query returns the contents of the questionable status condition register.

:QUEStionable:ENABle

:STATus:QUEStionable:ENABle

This command sets the enable mask of the questionable status event register.

:QUEStionable:PTR

:STATus:QUEStionable:PTR

This command sets the positive transition filter of the questionable status event register.

:QUEStionable:NTR

:STATus:QUEStionable:NTR

This command sets the negative transition filter of the questionable status event register.

:SYSTem Subsystem

:ERRor?

:SYSTem:ERRor[:NEXT]?

Return Parameters: Integer error number.

Query command is a request for the next entry in the instrument's error queue. Error messages in the queue contain an integer in the range [-32768, 32768] denoting an error code and associated descriptive text.

:ERRor:ALL?

:SYSTem:ERRor:ALL?

Return Parameters: List of integer error number.

Query command is a request for all entries in the instrument's error queue. Error messages in the queue contain an integer in the range [-32768, 32768] denoting an error code and associated descriptive text. This query clears the instrument's error queue.

:PRESet

:SYSTem:PRESet

Resets most signal generator functions to factory-defined conditions. This command is similar to the *RST command.

:VERSion?

:SYSTem:VERSion?

Returns the SCPI version number that the instrument software complies with [1999.0].

:LOCK

:SYSTem:LOCK

Locks (disables) front panel control.

:LOCK:RELease

:SYSTem:LOCK:RELease

Unlocks (enables) front panel control.

[:SYSTem:COMMunicate] Subsystem

:LAN:CONFig

:SYSTem:COMMunicate:LAN:CONFig DHCP|MANual|AUTO
:SYSTem:COMMunicate:LAN:CONFig?

This command sets the signal generator's internet protocol (IP) address.

• MANual. The user assigns an IP address to the signal generator.
• DHCP. The network assigns an IP address to the signal generator. If DHCP fails, manual configuration will be used.
• AUTO. The network assigns an IP address to the signal generator with a fallback to Auto-IP if DHCP fails. If both DHCP and Auto-IP fail, manual configuration will be used.

:LAN:DEFaults

:SYSTem:COMMunicate:LAN:DEFaults

This command restores the instrument's LAN settings to their factory default values.

:LAN:DESCription (not implemented)

:SYSTem:COMMunicate:LAN:DESCription <string>
:SYSTem:COMMunicate:LAN:DESCription?

This command defines the instrument's web description. The query returns the current saved setting.

:LAN:DHCP:TIMeout (not implemented)

:SYSTem:COMMunicate:LAN:DHCP:TIMeout {30}|60|90|120sec
:SYSTem:COMMunicate:LAN:DHCP:TIMeout?

This command enables the user to change the maximum length of time that the instrument will spend trying to acquire an IP address using DHCP. If the LAN Config Type is set to Auto, then the Auto-IP protocol will be used as a fall-back when time-out does occur. The DHCP timeout value is stored in the same non-volatile ram as the other LAN configurations. The query returns the current setting, not the saved setting.

Default 30 Seconds

:LAN:DOMain (not implemented)

:SYSTem:COMMunicate:LAN:DOMain <string>
:SYSTem:COMMunicate:LAN:DOMain?

This command defines the domain name of the signal generator's DNS server. This entry defines the DNS server for the signal generator LAN connection. The query returns the current setting, not the saved setting.

:LAN:DNS:DYNamic (not implemented)

:SYSTem:COMMunicate:LAN:DNS:DYNamic ON|OFF|1|0
:SYSTem:COMMunicate:LAN:DNS:DYNamic?

This command turns dynamic Domain Name System (DNS) on/off. The query returns the current setting, not the saved setting.

:LAN:DNS:OVERride (not implemented)

:SYSTem:COMMunicate:LAN:DNS:OVERride ON|OFF|1|0
:SYSTem:COMMunicate:LAN:DNS:OVERride?

This command enables you to override the DNS server that is returned by the DHCP server. The LAN configuration type must be set to Auto or DHCP to use this feature. The query returns the current setting, not the saved setting.

:LAN:DNS[:SERVer] (not implemented)

:SYSTem:COMMunicate:LAN:DNS[:SERVer] <ipstring>
:SYSTem:COMMunicate:LAN:DNS[:SERVer]?

This command defines the IP address of the signal generator DNS server. This entry defines the DNS server for the signal generator LAN connection. The query returns the current setting, not the saved setting.

:LAN:GATeway

:SYSTem:COMMunicate:LAN:GATeway <ipstring>
:SYSTem:COMMunicate:LAN:GATeway?

This command sets the gateway for local area network (LAN) access to the signal generator from outside the current sub-network. The query returns the current setting, not the saved setting.

:LAN:HOSTname

:SYSTem:COMMunicate:LAN:HOSTname <string>
:SYSTem:COMMunicate:LAN:HOSTname?

This command sets the signal generator's local area network (LAN) connection hostname. Maximum 29 characters are allowed. The query returns the current setting, not the saved setting.

:LAN:IDENtify (not implemented)

:SYSTem:COMMunicate:LAN:IDENtify ON|OFF|1|0

This command controls the LAN identify feature.

• ON (1). The command enables device identification by displaying the full-screen message "Identify: <IP Address>" on the signal generator's front panel; the LAN Status indicator will also show "IDENTIFY". For more information, refer to the Programming Guide.
• OFF (0). This command disables device identification by clearing the message on the signal generator's front panel and returning the LAN Status indicator to display the current network state. For more information, refer to the Programming Guide.

:LAN:IP

:SYSTem:COMMunicate:LAN:IP <ipstring>
:SYSTem:COMMunicate:LAN:IP?

This command sets the signal generator's local area network (LAN) internet protocol (IP) address for your IP network connection.

:LAN:KEEP:TIMeout (not implemented)

:SYSTem:COMMunicate:LAN:KEEP:TIMeout <value>
:SYSTem:COMMunicate:LAN:KEEP:TIMeout?

This command sets the length of time for the TCP Keep Alive setting.

Range 0 sec to 3600 sec

:LAN:RESTart

:SYSTem:COMMunicate:LAN:RESTart

This command restarts the network to enable changes that have been made to the LAN setup.

:LAN:SUBNet

:SYSTem:COMMunicate:LAN:SUBNet <ipstring>
:SYSTem:COMMunicate:LAN:SUBNet?

This command sets the signal generator's local area network (LAN) subnet mask address for your internet protocol (IP) network connection.

:SOCKet:ECHO

:SYSTem:COMMunicate:SOCKet:ECHO

This command turns the echo from the Model 845-M controller on or off. Echo is typically turned on only for a telnet session. The Model 845-M returns a ">>" prompt when ready.

UNIT Subsystem

UNIT:POWer

UNIT:POWer W|V|DBM|DB

*RST DBM

UNIT:FREQuency

UNIT:FREQuency HZ|MHZ|GHZ

*RST HZ

12. Battery Operation (B3 Option)

If your instrument is equipped with an internal rechargeable battery (B3 option) it can be operated without the external power supply. Fully charged battery is good for up to three hours of operation at full RF output power. The same external power adaptor (6 V @ 3 A) is used for the battery version as for the standard model for both normal operation and charging of the battery.

There are four operating modes that are also summarized in Table 2 below.

• normal operation. The external power supply is connected to the instrument and the device is turned ON (with the power switch on the rear panel turned ON). In this mode the instrument can be used as if no battery was present. The internal battery is not used and will NOT be charged.
• charging. The external power supply is connected to the instrument and the device is turned OFF (with the power switch on the rear panel turned OFF). In this mode the instrument is charging the internal battery. Once the battery is fully charged, the instrument goes into standby mode. Time required to complete charging is approx. four hours.
• standby. The internal battery is fully charged and the instrument is turned OFF.
• battery operation. The external power supply is disconnected and the device is turned ON. The internal battery is supplying the power until it is exhausted.

Table 2: Operating modes of an instrument equipped with internal battery.

Notes

1. [1] The instrument will switch off automatically when the battery is discharged. It is recommended that the power switch is turned to the OFF position when the battery is fully discharged.
2. [2] Termination of charging is automatic. The unit will then enter standby mode. The power adaptor can be left connected for any length of time.

During operation the approximate remaining battery capacity is indicated by the battery symbol visible in the upper right corner of the display (see Figure 9-a).

Hints for maximizing the battery running time:

1. Fully charge the unit before you use it. Toggle the power switch to ON and then OFF again while the instrument is powered by the external power adaptor. This will initiate a new charge cycle.
2. Charging time of a completely discharged battery can be up to 4 hours. IMPORTANT. The battery will only be charged when the instrument power switch is in the OFF position.
3. Batteries should always be charged in environments with the recommended ambient temperature, at very low or at elevated temperatures the charging is restricted by the battery's power management.
4. Check the battery indicator in the upper right corner of the display. It should indicate full charge when running on battery power after charging (Figure 9-a).
5. Power consumption of the instrument is reduced when the RF power is switched OFF (with the current selected parameter set).
6. Battery run time is maximal for ambient temperature between 15 and 25°C. Self-discharge of the battery is much faster at temperatures above 30°C.
7. Avoid storing the instrument in very hot places such as behind the windshield of a car parked in the sun.

Hints for maximizing battery life expectancy:

1. The battery will reach its best performance after the first few charge-discharge cycles.
2. Always use the external power adaptor supplied with the instrument for normal operation and charging. This will make sure that the charging counts as one specified.
3. Fully charge the instrument after running it from the battery for an extended period of time.
4. If an instrument with internal battery will be stored for a long period of time, fully charge it before storage, then remove the power adaptor and make sure that the power switch is in the OFF position. After storage, first charge the unit for 4-6 hours.

To replace the battery at the end of its lifetime, please contact BNC or one of its distributors.

13. Extended Power Range (PE3 Options)

Some instrument models are available with option PE3 that extends the power range towards lower power levels.

With these options PE3 installed, a mechanical step attenuator module is added. For the guaranteed minimum power level, please consult the respective datasheet.

In sweeps where the mechanical attenuator is switched, the minimum dwell time increases to 20 ms.

14. Maintenance and Warranty Information

14.1 Adjustments and Calibration

To maintain optimum measurement performance, the instrument should be calibrated every 24 months. It is recommended that the instruments be returned to BNC or to an authorized calibration facility. For more information please contact our Customer Service Department as indicated on www.berkeleynucleonics.com.

14.2 Repair

The signal generator contains no user-serviceable parts. Repair or calibration of the signal generator requires specialised test equipment and must be performed by BNC or its authorized repair specialists.

14.3 Warranty Information

All BNC instruments are warranted against defects in material and workmanship for a period of two years from the date of shipment. BNC will, at its option, repair or replace products that prove to be defective during the warranty period, provided they are returned to BNC and provided the preventative maintenance procedures are followed. Repairs necessitated by misuse of the product are not covered by this warranty. No other warranties are expressed or implied, including but not limited to implied warranties of merchantability and fitness for a particular purpose. BNC is not liable for consequential damages. The warranty on the internal rechargeable batteries (option B3) is one year from the date of shipment. Battery replacement is available through BNC and its distributors.

14.4 Equipment Returns

For instruments requiring service, either in or out of warranty, contact your local distributor or BNC Customer Service Department at the address given below for pricing and instructions before returning your instrument.

When you call, be sure to have the following information available:

• Model number.
• Serial number.
• Description of the failure.

Note: Model and serial number can be found on the rear of the unit or the power plug.

You will get a Return Merchandise Authorization (RMA) number from BNC, please put it on the outside of the package. Instruments that are eligible for in-warranty repair will be returned prepaid to the customer. For all other situations the customer is responsible for all shipping charges. An evaluation fee may be charged for processing units that are found to have no functional or performance defects.

For out of warranty instruments, BNC will provide an estimate for the cost of repair. Customer approval of the charges will be required before repairs can be made. For units deemed to be beyond repair, or in situations where the customer declines to authorize repair, an evaluation charge may be assessed by BNC.

15. Contact

Berkeley Nucleonics Corporation. 2955 Kerner Blvd., San Rafael, CA 94901.

Phone (415) 453-9955. Email info@berkeleynucleonics.com. Web www.berkeleynucleonics.com.

Model 845-M Signal Generator User Manual · based on the shared Signal Generators User Manual (Document Version 3.06). Programmers reference: Model 845-M Programmer’s Manual, Version 1.1, June 2011 (52 pages), verified for this page.