This involves a general Microwave 476 RF power meter of
which I have three of them.? I picked
them up with their sensors some time ago but haven¡¯t had time to give them a
full checkout.? This past week that went
on my ¡°to do¡± list.
?
They are fairly nice and have two sensors that cover the 10
& 100 mW maximum power input ranges.?
Being from the early 80¡¯s they are also somewhat antiquated utilizing an
electromechanical chopper made by Stevens Arnold which was quite ubiquitous in
many equipment in earlier years.
?
Out of the three I have, two seem to have a few
problems.? The third works well and is
very accurate in its power readings.? But
when starting to investigate the issues with the first two, I tried finding a
OP/SVC manual on this model and literally came up with nothing.? It appears that these units were original
government/military units and may have been made for that purpose.? The power sensors have had a soft metal foil
label added that sports a NSN (national stock number).
?
All three units are in nearly new condition and I would like
to get the two units working again but judging from the printed circuit board
inside, it would be a significant task to reverse engineer them.? All op amps and transistors have been
verified as good.? Attempts at an A/B
voltage/signal comparison with the good unit does show differences in
magnitudes but, again reverse engineering would have to be done to see how
these areas of the circuit are functioning.
?
Artek Media does have CD ROMs on later versions of General
Microwave watt meters but they are totally birds of a different color.? Has anyone ever come across a manual on the
units that I possess?
?
Thanks for reading.
?
Greg
RFI-EMI-GUY