AnsweredAssumed Answered

E4438C output level problem

Question asked by hudla on Jul 9, 2010
Latest reply on Nov 30, 2010 by hudla
Hello all,
after upgrading E4438C from firmware C.05.28 to C.05.76 I mentioned that some of my VEE programs don't work correctly, specifically when I set the some values of attenuator and ALC level manually. This short example fails:

:sour:power:att XX
:sour:pow:alc:lev YYDB

when XX=20 or XX=30 and YY=anything between settable values approx -15 dB to +15 dB (depending on frequency), the generator returns -222,"Data out of range;Value clipped to maximum user defined RF Output Limit." which is strange. For all the other attenuator and ALC settings everything is OK. The output level at the RF connector seems to be correct, however the error message makes me worry. I'm afraid of downgrading to FW C.05.28 since Agilent doesn't recommend it.

Could this error be caused by the FW upgrade? The generator selftest is OK, output level is in specifications, moreover the 20 dB and 30 dB sections are internally composed of 5+5+10 dB and 5+5+10+10 dB, respectively, thus other attenuator combinations should be affected too in the case of some damage.

Thank you for any suggestions,