I thought I had some notes here on this but can't find them. Anyway here
is my question:
I have a filter that was suppose to be a model 217, 500 Hz 9MHz. It came
in a used Ten-Tec Omni-C. There was far more loss through the IF than
what I would have expected with this filter inserted so I began
troubleshooting (I had an Omni-C for 24 years so I knew it wasn't
right). I could find nothing wrong with the filter switching circuit or
the two-gain setting buffer amplifier (provides more gain when this
filter is inserted). Next I disassembled my Argosy that had a nice, new
217 filter in it (I bought it myself some time back). The filter out of
my Argosy is clearly stamped a model 217 with another part number of
8036 on one of its crystals. This filter works great in either
transceiver. It is also an 8-pole filter. The suspect filter I had
finally pulled from the Omni-C transceiver has only 6-poles. It also has
no stamped on model number. There is a 8043 part number stamped on one
of its crystals.. I suspect it might be the Ten-Tec 250 Hz, 9MHz filter
as the passband is around 750Hz but with more attenuation than the 217 I
know is good. Any info?
73,
Jerry
--
Ralph Jerald "Jerry" Volpe
Amateur Radio Operator KG6TT
ARRL Member & VE
FISTS 12304
788 Chestnut Drive
Fairfield, CA 94533
kg6tt@arrl.net
510 325-7724
707 399-8838 FAX
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