Let me try again, perhaps a bit more terse and maybe less 
confusing/confused:
 Is there a particular circuit, board, or cable I should examine that 
would explain (a) normal receive operation on amateur bands below 14 MHz 
but (b) extremely high receive noise on bands above 14 MHz?
 There must be some signal path that is operative only on 20m-10m. I'm 
not knowledgeable enough to identify it.
--John K3GHH
On 05/19/2013 08:26 PM, K3GHH wrote:
 I'm encountering problems on wavelengths <30m. Operation seems normal 
on 160-30m. A few days ago I had no (well, maybe 4w) transmitter 
output on 20m, intermittent output on 17/15/12/10m, and main-tuning 
encoder clicking (with each step) on all bands above 10 MHz. I applied 
Deoxit to the pins of all circuit boards (and out/in 10 times) and 
their cables, and the A&B front panel cables, and that seemed to do 
the job. I once again have full power on all bands.
 But I also have S9+40 noise (if I'm using the S-meter correctly) on 
20m and higher (frequency) bands. No signals can be heard under that. 
(With RF Gain = 100, "signal level" is about S=0.5 when 160-30 are 
selected; it jumps to +40 to +50 when 20m is chosen and drops to 
+30-+40 on 17-10m.)
 As a test, I fired up the old Icom 706IIG and immediately worked a 
strong VP5 on 14.005 MHz. I put the antenna back on the Orion and 
heard the VP5 briefly, but then the noise returned and now nothing is 
audible on 20m.
Any suggestions? Wish I hadn't put all of those cabinet screws back in!
  
--
--- John, K3GHH
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