Contact an Expert

Thread: E4440A error handling reference level via SCPI


Permlink Replies: 5 - Pages: 1 - Last Post: Sep 7, 2012 9:32 AM Last Post By: tabbott
miyamky

Posts: 111
Registered: 08/03/09
E4440A error handling reference level via SCPI
Posted: Jul 19, 2012 4:42 PM
Click to report abuse...   Click to reply to this thread Reply
We're using firmware A.11.20

If my PSA is at a low attenuation, say 0 dB, and I issue the SCPI command to set the reference level (it's embedded in a string of commands) high, say 20 dBm, I get no errors reported but (probably as expected) the PSA sets the reference level to -10 dBm.

I've since fixed the code to set the attenuation first but I would've thought that setting the reference level to something other than what is specified would produce an error.
zwm

Posts: 2
Registered: 07/08/12
Re: E4440A error handling reference level via SCPI
Posted: Jul 20, 2012 7:12 PM   in response to: miyamky in response to: miyamky
Click to report abuse...   Click to reply to this thread Reply
I think it is the restriction of the max mixer input level of the E4440A, you can find it at AMPT/NEXT/NEXT/MAX MIXER LVL (normally is -10dBm).

You should make sure that the input level to the mixer is less than the max value, i.e. the RF Input Level - Int AttMax Mixer Level. The E4440A ensures this in top priority, so the reference level may be automaticly adjusted.
miyamky

Posts: 111
Registered: 08/03/09
Re: E4440A error handling reference level via SCPI
Posted: Jul 23, 2012 10:19 AM   in response to: zwm in response to: zwm
Click to report abuse...   Click to reply to this thread Reply
My concern is not the mechanism, it's that the firmware responded that the command succeeded when it actually did NOT.
tabbott


Posts: 1,483
Registered: 07/24/09
Re: E4440A error handling reference level via SCPI
Posted: Jul 26, 2012 3:24 PM   in response to: miyamky in response to: miyamky
Click to report abuse...   Click to reply to this thread Reply
Hi -

When you remotely set the analyzer to a value past its range for the current operating conditions, it will instead set the value to the maximum and will put an error in the error queue to the effect of: -222,”Data out of range;value clipped to upper limit.”

You can query the error queue by sending the command: syst:err?

Regards -
miyamky

Posts: 111
Registered: 08/03/09
Re: E4440A error handling reference level via SCPI
Posted: Aug 16, 2012 3:17 PM   in response to: tabbott in response to: tabbott
Click to report abuse...   Click to reply to this thread Reply
That's not true (at least for my firmware version).

Try:

:POW:ATT 0
:DISP:WIND:TRAC:Y:RLEV 20DBM
*ERR?

It will set the referencel level to -10DBM and *ERR? will return +0,"No error"
tabbott


Posts: 1,483
Registered: 07/24/09
Re: E4440A error handling reference level via SCPI
Posted: Sep 7, 2012 9:32 AM   in response to: miyamky in response to: miyamky
Click to report abuse...   Click to reply to this thread Reply
Hi -

I apologize, but only X-Series Analyzers report an error. PSA does not. For PSA the work around would be to query the value after you set it to make sure it is the value that you want and has not been clipped. Here is an example showing an N9030A actually returning an error after setting the reference level too high:
-> SYST:ERR?
<- +0,"No error"
-> :POW:ATT 0
-> :DISP:WIND:TRAC:Y:RLEV 20 DBM
-> SYST:ERR?
<- -222,"Data out of range;The value 20 was clipped to the maximum value of -20."

Regards -

Point your RSS reader here for a feed of the latest messages in all forums