I recently replaced the 218 filter in the N2 position of my Omni VI (opt 3)
with a TT 219 (250 Hz CW) filter that I removed from an Omni V. The filter
was purchased from TT in 2001 and was working when removed from the Omni V.
However, in the Omni VI it doesn't appear to work. I did move the gain
jumper as per the instructions to the high setting.
The reason that I think it is not working is that when I monitor the audio
spectrum (using MixW) the only change I see when I engage the N2 filter is a
general lowering of the entire audio frequency range, there is not one
specific frequency range that stands out. In contrast, when I engage the 217
(500 Hz CW) filter in N1, I see a definite highlighted area of reception
(2100 - 2600 Hz in USB). These tests were done with the 6 MHz filter in the
2.4 kHz setting. I reinstalled the 218 filter and verified that it is
working.
I looked at the filter itself and examined the solder joints for broken
connections and didn't see any problems.
73,
Mark
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