[Test-Equipment] (no subject)

[w3sz]

Hello, All,

I have an HP3586C Selective Level Meter that I use mostly for VLF  
listening and frequency calibration work.

Today the HP3586C started misbehaving; first, the frequency tune encoder  
started occasionally skipping.
That is, rotating it would produce no effect for 30-60 degrees, then it  
would work OK.  Then it
started only tuning down in frequency, no matter which way the knob was  
rotated.  It is currently
working properly, but it has cycled back and forth between working  
properly and not doing so several
times this afternoon.

I did the brainless stuff like reseating the boards / modules / internal  
connectors with no apparent effect.

As I don't have schematics I am somewhat at a loss for troubleshooting.

Has anyone else noticed a similar problem with a similar HP unit and if so  
what was the diagnosis /
treatment?

I don't have any manuals for the unit, though today I ordered the  
operating, calibration, and parts manuals
on CD from http://www.fullnet.com/u/tomg/manuals.htm .  Unfortunately,  
they don't include the schematics
and I haven't found the service manuals [parts 1 and 2] for less than  
$180.00.

Thanks in advance, and

73,

Roger Rehr
W3SZ

-- 
Roger Rehr
W3SZ
http://www.qsl.net/w3sz