Here's a brain teaser for all you Orion experts. My 565 running ver 3.032 has
developed a couple of problems that I was hoping would be a firmware issue but
it's looking more and more like a hardware problem. I'm looking for some ideas
about where to start troubleshooting.
In a nutshell the two problems (which may just be different symptoms of one
problem) are these:
1. All signals received by the main rcvr on 20M only are extremely garbled and
distorted. This condition is not dependent on mode and all other receiver
functions such as S-meter operation, AGC, BW and PBT functions seem to be
unaffected. Operation of the sub-receiver is normal. One interesting note is
that a signal disappears when I engage the hardware NB, which is probably just
an indicator that the NB thinks it's seeing noise and just doing its job.
2. When both VFO's display the same frequency, there is a difference in
received frequency between the two receivers. This is present regardless of
band, but the difference is not the same from band to band. The worst I've
noticed is 200 hz offset on 20M, but other bands exhibit 50-100 hz delta
between the receivers in spite of displaying the same frequencies. It
doesn't matter how the two receivers arrive at the same frequency, either by
pressing the A>B button or configuring both Main and Sub recvrs to be
controlled by VFO-A.
This all came on as an intermittent condition. I would notice that during
operation on 20M, received signals would suddenly jump by 100-200 hz and I
would have to re-tune to get back on frequency. I was assuming that the
transmitted frequency was jumping as well, but I haven't verified that as yet.
Anyway, after the "jump" occurred, the signals would sound warbly and quivery
(technical terms for "trashy"). No matter their signal strength they sounded
watery like they were coming from over the North Pole. If I were to select a
different band and then return , the receiver would "slide" a few hertz back
onto frequency before settling.
I have
sometimes noticed that just before this would happen there would be a rise in
noise
level, like precipitation static. While the rcvr is off-frequency, there is a
lot of noise/hash that is in sync with other signals some as far
away as 50 khz. It resembles being at field day in close proximity to
several
transmitters. Even though they are way out of the bandpass of the
filters and too far away to hear a cw tone, I
can copy them by listening to the hash.
I have re-flashed the firmware and performed a few master-resets, etc... with
no change. The problem is no longer intermittent and I'm looking for ideas
while I decide how much $$$ I want to put into repairing a really fine, but
old, radio.
73, Art/N4UC
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