Copyright: (c) Copyright Agilent Technologies, 2000, 2001


About Troubleshooting

The Troubleshooting information is available in several forms to help you isolate and solve problems you encounter with your analyzer or measurements.

•	Installation Help: The Diagnostics chapter of the Installation and Service Guide helps you troubleshoot installation and configuration problems, or problems with your measurement hardware.

•	Boot Log: When you start the analyzer, the software creates a boot log file.

•	VSA Measurement and Status Information: Error and Status Messages appear in the display, providing information about the current measurement and hardware.

•	Other error messages:

−	Calibration error messages

−	Source error messages

•	Information for troubleshooting measurements:

−	Digital Demodulation measurements

−	cdma2000 measurements

−	W-CDMA measurements

−	OFDM measurements

−	ADS measurements


Boot Log

When you start either the Vector Signal Analyzer or the Spectrum Analyzer application, the software creates a boot log. Among other things, the log lists the hardware found. This can be useful for troubleshooting.

To access the boot log, click Help > About > Boot Log.


Exclude Devices

When you start the analyzer, the software looks for all connected VISA GPIB devices and sends a selective device clear (viClear) and IDN? query to the device to determine its model number. This can cause problems for non-SCPI devices or if the devices are in the middle of a process. The 89600 software also requests a list of available devices from the I/O libraries. the default VISA configuration is to find all devices available at the time of the request.

Symptoms

•	Instruments or devices get set to remote state when you start the 89600 software even if the devices are not controlled by 89600.

•	When you start the 89600 software, errors occur on other instruments or devices that aren't controlled by 89600.

Solution

You can exclude specific devices from the 89600 discovery process. To do this, perform the following steps:

1.	Close any 89600 Vector Signal Analyzer or Spectrum Analyzer application you have open.

2.	Edit the file "VsaVisaTemplate.txt". Then save the file using the name "VSAVisaConfig.txt", listing the devices you identify to be excluded.


Gaps in Displayed Data

In some cases,  what appears to be gaps in the displayed data is actually a video card problem.

Symptom

Unexpected gaps in displayed data.

Solution

Upgrade your video driver. A temporary solution is to change the refresh rate for your display. Note that if you reboot your computer you must change the refresh rate again.


Hardware Not Found

If you connect new hardware to your analyzer, you must close all instances of the 89600 software, then restart the software before the analyzer will recognize the new hardware.


LAN or GPIB Problems
LAN or GPIB Connection Problems

Some instruments (such as the Agilent E4406) interface to the computer via LAN or GPIB using Agilent IO libraries. This topic documents some possible interface problems.

For more detailed information on troubleshooting LAN/GPIB interface problems, see the Diagnostics chapter of the 89600 Installation and Service Guide. To open the PDF file, click here.

The first thing to check is that the interface cables are connected before you turn on the measurement hardware. Check the cable connections, then cycle power on the measurement hardware.

More than one interface configured to a device

You should not have more than one interface configured for each instrument, either from one computer or multiple computers. This is especially easy to do for LAN interfaces. If an instrument is connected to a LAN, it can be accessed from any computer that is also connected to the LAN. If two computers on the LAN are configured to point to the instrument, they may try to access the instrument simultaneously.

Symptoms

•	Corrupted data

•	Measurement timeout

Solutions

Run IO config, remove or disable the unneeded interface. An easy way to disable the interface is to add extra, meaningless characters to the Remote Hostname entry. Then when you want to re-enable the instrument, you need only remove the extra characters.

Configured instrument disconnected or turned off

After you have run the 89600 software with a specific hardware configuration, the software looks for that hardware every time you start. This can take a long time.

Symptoms

Long startup time for 89600 software.

Solutions

Run IO config, remove or disable the unneeded interface. An easy way to disable the interface is to add extra, meaningless characters to the Remote Hostname entry. Then when you want to re-enable the instrument, you need only remove the extra characters.

Incorrect subnet mask set for E4406

Your E4406 must have a subnet mask set appropriately for the IP address.

Symptoms

Software cannot find the E4406. You cannot communicate with the E4406 in any way (pinging or through VISA Assistant).

Solutions

If the E4406 IP address begins with "10.", set the E4406 subnet mask to "255.0.0.0". If the IP address begins with anything other than "10.", set the E4406 subnet mask to "255.255.0.0". For step-by-step instructions, see "Configuring LAN Interface" in the "Configuring IO Interfaces" chapter of the Installation and Service Guide .

Unlock Front Panel error

Symptoms

Other applications can't communicate to some GPIB instruments that are not used by the 89600 software when the Unlock Front Panel hardware parameter is set to True (set under Utilities > Hardware > ADC1 > Configure).

Solutions

Set Unlock Front Panel to False or try asserting the REN line before sending a command to the instrument.  The 89600 software deasserts the REN line when Unlock Front Panel is set to True. Some GPIB instruments won't accept commands properly when the REN line is deasserted.


Printing Problems

Symptom

Titles do not print when you print help text.

Solution

Change the color scheme for your display. If you are using a "high contrast" or "high color" scheme for Microsoft Windows, the titles will not be printed with help text.


Triggering Problems
Trigger Level and Delay Issues

The 89600 software relies on the input hardware to do the triggering. The input hardware must use a trigger level supplied by 89600 software, and return back to 89600 a delay value indicating exactly where the trigger occurred.

However, once 89600 gets this data, it passes through the 89600 software resampling filters and time corrections before the data is displayed. These two steps can cause unexpected effects on the trigger level and delay.

Resampling effects

The 89600 resampler acts like a variable-bandwidth low-pass filter, which is used to reduce the bandwidth of the raw input data to match the bandwidth desired by the user. If there is very much energy in the region that gets filtered away, the signal level and shape will change as a result of the resampling, resulting in a time waveform that does not match the original waveform that the triggering took place on. This effect is most pronounced if the input hardware has widely spaced "cardinal" spans, which is the case for the E1438 and E1439 VXI input modules and the Infiniium oscilloscope. The effect is also more pronounced when the signal is far from the 89600 center frequency.

If the user bandwidth matches the hardware cardinal span, and the hardware produces data at the native 89600 oversample ratio (like the E1438 and E1439 VXI input modules) a non-triggered measurement will not use the resampler. However, when triggering is turned on, the resampler is always used because the resampler is used to get exact sub-sample trigger delays. Note that the resampler will attenuate out-of-band signals even if the bandwidth is not changed, so the signal shape can change as a result.

Time Correction effects

For the E1438 and E1439 VXI input modules, the 89600 time corrections are used to correct for hardware digital filtering effects. The digital filters have non-linear phase, so the time corrections also have non-linear phase. In addition, time correction usually changes the amplitude of the signal. This means that the signal shape and amplitude may change as a result of the time corrections, as compared with the original signal on which the trigger was detected. The correction varies with frequency, so a signal at the 89600 center frequency will be affected differently than a signal near the band edge.


Error and Status Messages

The analyzer may display error and status messages to inform you of a condition that may need attention.

The following illustration shows the location of these messages.

•	Trace indicators inform you of conditions that occurred when a trace was created.

•	Measurement status messages show the status of the current measurement (for example, if the measurement is in the process of filling the time record).

•	Calibration status messages show the current calibration state for the selected hardware.

•	External reference lock state messages indicate the lock state of the external reference for measurement hardware that has an External Reference In capability

Note

For source (signal generator) errors, see Source Error Messages.
For calibration errors, see Calibration Error Messages.

For details, click on the names of any of the messages listed below:

<blank> (External Reference Lock State)

Acquiring Pre-trigger Data

ALL POINTS

Average Complete

Average in Progress

CAL?

CARRIER LOCK?

DATA?

Demod: Not enough data.

Doing 3G demodulation

Doing CDP calculations

Doing descrambling

Doing EVM calculations

Doing final timing estimation

Doing secondary timing correction

Doing secondary timing estimation

Doing timing compensation

Doing timing correction

Doing timing estimation

EQ

EXT REF

Filling Time Record

INACTIVE CHAN

INT REF

MEAS OFFSET?

Measurement Paused

Measurement Running

Needed

NO DATA

None

OK

OV1/OV2

Playback Measurement

PULSE NOT FOUND

PULSE TOO SHORT

Real-time Average Complete

Real-time Average in Progress

Real-time Measurement

RNG

Signal Track Measurement

Starting 3G demodulation

SYNC NOT FOUND

UNLOCKED

Waiting for Settling

Waiting for Trigger

Warmup


Calibration Status Messages

Messages about the current calibration status are displayed in the lower right corner, as shown in the following illustration.

CAL:	This area lists the status of calibration. The possible calibration states are: • OK:  The calibration data is current. • Needed:  The hardware has not been calibrated, or the calibration data is out of date. • Warmup:  The temperature of the measurement hardware is changing. (This probably means the hardware was recently turned on.)  When the temperature stabilizes, this state will change to either OK or Needed. • None:  The current hardware configuration does not support calibration (for example, simulated hardware or ADS interface). You can initiate a single calibration or extended calibration by right clicking in this area, then selecting from the list.
A	External amplitude calibration status. Double-click this area to open the Amplitude calibration dialog box. When any of the checkboxes in the dialog box are selected, the A is dark to indicate that one or more amplitude calibration parameters is active. If all the checkboxes are cleared, the A is greyed to indicate that all amplitude calibration parameters are inactive.
F	External frequency calibration status. Double-click this area to open the Frequency calibration dialog box. When the Use External Down Converter checkbox in the dialog box is selected, the F is dark to indicate that the parameter is active. If the Use External Down Converter checkbox is cleared, the F is greyed to indicate that the parameter is inactive.
E (abs or rel)	Fixed equalization status. Double-click this area to open the Fixed calibration dialog box. When the Fixed Equalization checkbox in the dialog box is selected, the E is dark to indicate that the parameter is active. If the Fixed Equalization checkbox is cleared, the E is greyed to indicate that the parameter is inactive. The letters following the E indicate whether equalization is absolute or relative.
See also

Error and Status Messages


External Reference Lock Status Messages

These messages, which appear at the bottom of the window, indicate the status of the external reference.

Message	Explanation
<blank>	External reference status message. The analyzer uses the reference signal generated internally by the input module.
EXT REF	External reference status message. The analyzer is locked to a signal at the external reference connector.
INT REF	External reference status message. The analyzer is locked to the clock signal provided by the reference master.
UNLOCKED	External reference status message. The Lock Reference state for a piece of hardware that is used in conjunction with other hardware modules has been changed from True to False. Or the external reference for a piece of hardware that has Lock Reference set to True could not lock to the external reference. If Ext Reference Frequency for an 89605B or 89606B module is set to 13 MHz and a 13 MHz signal is not connected to the Ext Ref In connector, calibration will fail.
See also

Error and Status Messages


Measurement Errors

Measurement error messages appear in an error dialog box.

Note

For source (signal generator) errors, see Source Error Messages.
For calibration errors, see Calibration Error Messages.

Demod: Not enough data. (Measurement step 'Demod' encountered this error)	Measurement error dialog box. The current hardware setup could not acquire enough time samples to complete the requested Digital Demodulation measurement. The Digital Demod Result Length and Search Length algorithms require a minimum of 10 Symbols for Result Length. Typically this error is related to the Alias Protect setting for the ESA or Sampling Mode (documented under "Operation" in the product note) for the Infiniium oscilloscope.


Measurement Status Messages

Measurement status messages appear at the bottom left of the 89600 window. The messages provide information about the current measurement.

Acquiring Pre-trigger Data	Doing timing estimation
Average Complete	Filling Time Record
Average in Progress	Measurement Running
Doing 3G demodulation	Measurement Paused
Doing CDP calculations	Playback Measurement
Doing descrambling	Real-time Average in Progress
Doing EVM calculations	Real-time Average Complete
Doing final timing estimation	Real-time Measurement
Doing secondary timing correction	Signal Track Measurement
Doing secondary timing estimation	Starting 3G demodulation
Doing timing compensation	Waiting for Settling
Doing timing correction	Waiting for Trigger
Message	Explanation
Acquiring Pre-Trigger Data	If a negative trigger delay is specified, the analyzer must collect a certain amount of data to perform a valid measurement when it receives a trigger signal.  If acquiring the data will take very long (more than a few seconds), the analyzer displays this message.
Average Complete	The analyzer has finished an averaged measurement.
Average in Progress	The analyzer is making an averaged measurement.
Doing …	3G status message. These messages are indicators of what is happening during various stages of a W-CDMA or cdma2000 demodulation.
Filling Time Record	When you start a real-time measurement that has a long time-record length, the analyzer displays "Filling Time Record" until it fills the time record. For real-time measurements, the analyzer is able to process the time record as it's being filled. "Filling Time Record" informs you that the time record being processed (and displayed) is not a full time record. In some cases, such as digital demod operations, the analyzer acquires extra data before and after filling the time record. The display does not change when the analyzer is collecting data outside the time record.
Measurement Paused	A measurement has been paused. You can continue the measurement by clicking the Pause button [image] or start a new measurement by clicking the Start button [image].
Measurement Running	The analyzer is making an unaveraged, non-real-time measurement.
Playback Measurement	The analyzer input is from a recording.
Real-Time Average Complete	The analyzer has finished a real-time averaged measurement.
Real-Time Average in Progress	The analyzer is making a real-time averaged measurement.
Real-Time Measurement	The analyzer is making a real-time measurement.
Signal Track Measurement	The analyzer is making a measurement with Signal Tracking turned on.
Starting …	3G status message. These messages are indicators of what is happening during various stages of a W-CDMA or cdma2000 demodulation.
Waiting for Settling	The analyzer is waiting for internal digital filters to settle before starting the measurement.
Waiting for Trigger	The analyzer is waiting for trigger conditions to be met before starting a measurement.
See also

Error and Status Messages


Trace Indicator Messages

Trace indicators, displayed in the upper right corner of the trace grid, provide information about the currently-displayed trace data. If you click on the Trace Indicator, the analyzer displays a brief description of the condition that caused the error.

Only one trace indicator can appear at a time. Therefore, the analyzer uses the following priority to determine which trace indicator to display if more than one exists:

NO DATA	Highest Priority
DATA?
OV1 and/or OV2
CAL?
PULSE NOT FOUND
SYNC NOT FOUND
CARRIER LOCK?
EQ
RNG
ALL PTS	Lowest Priority

For details, click on the names of any of the indicators listed below:

ALL POINTS	NO DATA
CAL?	OV1/OV2
CARRIER LOCK?	PULSE NOT FOUND
DATA?	PULSE TOO SHORT
EQ	RNG
INACTIVE CHAN	SYNC NOT FOUND
MEAS OFFSET?
Message	Explanation
ALL POINTS	Trace indicator. Show All Frequency Points is turned on.
CAL?	Trace indicator. CAL? means the data contained in the trace is uncorrected or not fully corrected for one of several reasons. CAL? appears if calibration data is missing because you have changed hardware configurations and have not yet calibrated. It also appears if the hardware's environment (e.g. temperature) has changed sufficiently to invalidate the previous calibration. In either case, you should perform a Single Cal. CAL? also appears if Apply Corrections to Data is off. Another cause for CAL? is the absence of factory calibration files for the 89605 or E2730 modules. CAL? also appears if the User Calibration file was not created properly.
CARRIER LOCK?	Trace indicator that may appear when using Digital Demodulation to demodulate VSB signals. It informs you that the analyzer is unable to lock to your signal. For further details, see Setting up a Digital Demodulation Measurement. This message is also displayed for W-CDMA and cdma2000 measurements when the analyzer is unable to lock to the signal.
DATA?	Trace indicator, "Data is questionable relative to the current setup." This can happen if a measurement is paused and, for instance, you change the span. If a measurement is paused, changing most measurement parameters (those under the MeasSetup menu) result in questionable data (DATA?). For more information about what caused the data to be questionable, click on DATA?, and the analyzer will display an explanation.
EQ	Trace indicator. The digital demodulation equalizer is on.
INACTIVE CHAN	Trace indicator. With channel data in W-CMDA or cdma2000 displayed, the currently selected channel is not active.
MEAS OFFSET?	Trace indicator. For W-CDMA or csma2000 measurements, most results use the measurement offset and measurement interval parameters. A few results do not, and instead use the first slot (PCG) of the data. For these results, "MEAS OFFSET?" is displayed if the measurement offset parameter is non-zero or the measurement interval parameter is greater than one. This is a reminder that these results don't use the current measurement offset or measurement interval.
NO DATA	Trace indicator. There is no valid data associated with this trace. This message appears for the following reasons:
	The trace data has become invalid due to a measurement parameter change, such as changing instrument modes or selecting a different average type. In these cases, NO DATA is cleared when a new trace is acquired. The trace data cannot be computed. Some likely causes are if trace data is turned off, or you're trying to display an empty data register, or an undefined math function. NO DATA also appears if you try to display a result that cannot be computed for the current measurement setup (such as time data in scalar mode, coherence if not in rms average, correlation data if in scalar mode, or instantaneous spectrum in time average. The displayed math function cannot be computed. For example, a math function that uses an empty data register or an undefined math function.
OV1/OV2	Trace Indicator. The OV1/OV2 indicators appear if the trace was created from data that contained an ADC overload. For averaged data, this means that an ADC overload occurred in at least one average. The analyzer cannot make valid measurements with ADC overloads--ADC overloads corrupt measurement data. If an ADC overload occurs, increase the range or decrease the amplitude of your input signal, and perform another measurement.
PULSE NOT FOUND	Trace Indicator. For details, see online help for pulse search on/off.
PULSE TOO SHORT	The Detected pulse length is shorter than specified measurement offset . No data is displayed."
RNG	Trace indicator. A PDF or CDF found a sample with magnitude greater than 100% of the input range.
SYNC NOT FOUND	Trace Indicator. For details, see help for pulse search on/off and sync search on/off.
See also

Error and Status Messages


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Acknowledgements

The following products are mentioned in one or more places in the Agilent 89600-series documentation.

Product	Acknowledgement
Adobe® and Acrobat®	These products are trademarks of Adobe Systems Incorporated.
Microsoft®, Windows NT®, Windows®, and MS Windows®	These products are U.S. registered trademarks of Microsoft Corporation.
MS Excel, MS Word, MS Office, VBScript	These products are products of Microsoft Corporation.
MATLAB	MATLAB is a product of The MathWorks, Inc.


The Documentation Roadmap is not installed on your system.


1999-2002, Agilent Technologies


This documentation is not installed on your system.


This document was not available for inclusion in the online help. You can download the PDF from the 89600 [image] Web page .


This document was not available for inclusion in the online help. You can download the PDF from the 89600 [image] Web page .


This document was not available for inclusion in the online help. You can download the PDF from the 89600 [image] Web page .


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


Service

If your Agilent 89600-series analyzer needs service, contact your local Agilent Sales and Service representative or visit the 89600-series Technical Support web page at:

 www.agilent.com/find/89600


For Internal Use Only

The following commands may be useful in troubleshooting problems associated with the E2730A tuner.  These commands can be sent to the E2730A via the VISA Assistant utility program that comes with the Agilent VISA I/O libraries.  Some of these commands cause permanent setting changes for the E2730A and should be executed only by qualified personnel.

Table 3-3.  Reference Selection

Command	Response	Description
REF nrf		Set Reference to Internal or External 0 = Internal  Reference 1= VXI Bus Reference  2 = External Reference
REF?	REF nr1	Request Reference Setting Reset: REF 0 Example: REF 1
Table 3-4.  Reset

Command	Response	Description
*RST		Set all tuner device messages to the reset values.
Table 3-6.  Frequency Operations

Command	Response	Description
FRG?	FRG nr2, nr2	Request the lower and upper frequency limits of the tuner. Reset: n/c Example: FRG 0002.0000,2700.0000
FRQ nrf		Set tuned frequency of tuner. Range: 0 - 2700 MHz, resolution is 100 Hz.
FRQ?	FRQ nr2	Request current tuned frequency. Reset: FRQ 0020.0000 Example: FRQ 2699.9999
TSP nrf		Selects tuning resolution 1 = 100 Hz, 2 = 1 kHz
TSP?	TSP nr1	Request current tuning resolution Reset = TSP 2 Example = TSP 1
Table 3-7.  Tuner Attenuation

Command	Response	Description
ATN nrf		Set the tuner attenuation. Range 0-60 dB, resolution is 2-dB.
ATN?	FRQ nr2	Request current tuner attenuation. Reset: ATN 000 Example: ATN 030
Table 3-10.  Communications Messages and SRQ Operations

Command	Response	Description
*IDN?	*IDN str	Request the tuner's identity.  Response is manufacture, model, serial number, and firmware version number. Reset: n/c Example: *IDN Agilent Technologies, US39440101, 01.00.00
Table 3-12.  Master/Slave Messages

Command	Response	Description
LOM nrf		Set the LO Mode. 0 - Independent 1 - Master 2 - Slave
LOM?	LOM nr1	Request current LO Mode. Reset: LOM 0 Example: LOM 1
Table 3-13.  Compatibility Messages

Command	Response	Description
BND nrf		Set Preselector Band
BND?	BND nr1	Request Preselector Band.  Response depends on current tuned frequency.  From 0 to 982.0000 MHz, BND 1 is returned. From 892.0001 to 2700.0000 MHz, BND 2 is returned.
BYP nrf		Set the Preselector Bypass mode.
BYP?	BYP 0	Request the Preselector Bypass Mode Status.
Table 3-14.  User Configuration Messages

Command	Response	Description
CFG nrf		Set configuration status on or off.  Normal operation is with configuration off (0).  When configuration is on (1) EEPROM data in the tuner may be written.
CFG?	CFG nr1	Request status of the configuration mode. 0 = Unit is set to operation mode 1 = Unit is set to configuration mode Reset: n/c Example: CFG 0
#FFE nrf		Set nr2 output format.   0   nr2 output format  = xxxx.xxxx    1   nr2 output format  = xxxx.xxxxx    2   nr2 output format  = xxxxx.xxxx    3   nr2 output format  = xxxxx.xxxxx
#FFE?	#FFE nr1	Return current nr2 output format. Example: #FFE 0
Table 3-15.  Factory Configuration Messages

Command	Response	Description
#CDT nrf,nrf,nrf		Set the date of configuration. Field             Parameter              Range    1                  Month 1 to 12    2                  Day 1 to 31    3                  Year 0000 to 9999
#CDT?	#CDT nr1,nr1,nr1	Request the configuration date. Default: #CDT 01,01,2000 Example: #CDT 06,25,1997
#COP		Set the options configured in the unit. Bit             Options   0                 TBD                 1                 TBD                 2                 TBD                 3                 TBD                 4                 TBD                 5                 TBD                 6                 TBD                 7                 TBD
#COP?	#COP nr1	Request the options configured in the unit. Default: #COP 00000 Example: #COP 00000
#CSN?	#CSN nr1	Request the unit's serial number. Default: #CSN  US00000000 Example: #CSN US39440722
#EED 0		Load default configuration data to EEPROM.
#EED?	#EED nr1	Return current value in EEPROM. Example: #EED 43690
#MDL		Set the unit's model number.
#MDL?	#MDL str	Request the unit's model number. Default: #MDL ′E2730A  ′ Example: #MDL ′E2730A  ′ Note:  The first five (E2730A) of the seven characters must never change.  If they do, then the EEPROM will be reset upon the next power-up of the unit.
#WJI?	#WJI nr1	Request the unit's vendor serial number. Example: #WJI 00009
#YCL		Initiates a Calibration of the YIG DAC.  This command should only be issued by qualified personnel and only after the tuner is at normal operational temperature.
#YCL?	#YCL nr1	This returns the status of the most recent YIG DAC calibration. Results:  -1 - Complete and Uncalibrated +0 - Complete and Calibrated +1 - Calibration In Progress Example: #YCL +0
#YIG nrf,nrf		Set the YIG DAC tuning voltage values at 0 MHz and 2700 MHz respectively.  This command should only be used by qualified personnel.
#YIG?	#YIG nr1,nr1	Request Current YIG DAC Settings. Example: #YIG +00000,+00000
Table 3-16.  Maintenance Messages

Command	Response	Description
ATI nrf		Set IF attenuators. Range: 0 to 30,  2-dB steps
ATI?	ATI nr1	Request current IF attenuator setting. Reset : ATI 00 Example: ATI 14
ATR nrf		Set RF attenuators. Range: 0 to 30 - 2 dB steps
ATR	ATR nr1	Request current RF attenuator setting. Reset:  ATR 00 Example: ATR 22
PAM nrf		Turn Pre-Amplifier OFF and ON.  0 = OFF  -  1 = ON Reset: 1 ; Default: 1
PAM?	PAM nr1	Request Pre-Amp Setting.