[Test-Equipment] HP 141 analyzer low gain

[Gary Schafer]

I finally got around to doing a little work on my old HP 141 spectrum 
analyzer. Had to repair the input attenuater. Someone had smoked the 10 
db front end pad. Replaced resistors and works ok now.

The analyzer has low overall gain. Down about 20 db. If I turn the gain 
adjustment up all the way (front panel screw driver adjustment) I can 
get the gain up to about -10 db down. But it is not linear there. When 
changing the step attenuaters the crt does not indicate 10 db each time.

With the gain calibration backed off to where the analyzer is 20 db 
below where it should be calibrated everything seems to work fine except 
of course the calibration is off by 20 db.

Any thoughts on where to look for the problem?

Thanks
Gary  K4FMX