On 8/27/19 8:14 PM, Mike Besemer wrote:
I recently acquired an HP8643A.? It **SEEMS** to work ok,
althoughadmittedlyI have not used it very much yet.?
On initial power on, it displays? --- Calibrating --- for a very long
time¡ perhaps 3 minutes or so.? When the --- Calibrating --- finally
goes away, it displays Hardware Failure 14 and Calibration Error 2,
along with theResult Code 14.020122*WITHOUT* a plus or minus sign in
front of it.?According to the service data, a result code without a sign
in front of it indicates a calibration errorand require additional
action to return the instrument to working condition.?I haven¡¯t found
anything on either the Hardware Failure 14 or the Calibration Error 2 in
the manual yet.?
I have checked the P/S voltages and all are in tolerance and the max
ripple I see is about 20 mV, although I have not seen a spec in the book
for ripple.?There is **SOMETIMES**a P/S fail LED lit on the I/O board,
but it always goes away.? Obvious this is suspicious, but I don¡¯t know
if it means anything or not.
I pulled the I/O board and looked down at the P/S boards and I don¡¯t see
any leaky or swollen caps.?
The Serial Number is 3512A01553 and the device has Options H02 and K01
installed.?
Any advice would be appreciated.?I spent some time getting my HP8924C¡¯s
up and running recently, so I¡¯m not afraid to get in up to my elbows,
but sure would appreciate some direction.
For that PS Fail LED, my money is on a tantalum capacitor trying to
short. I'd look around for that and then see if the error code goes
away. This family of signal generators performs extensive self-tests;
it's easily possible that one of the power rails isn't quite right at
startup (i.e., when those tests are run) and then straightens up later on.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
Dave McGuire