[Amps] SB-220 tick,tick,tick

[mikflathead at aol.com]

 Being very care full with the top off and the lights off you may be able to see the spark.
 
 
-----Original Message-----
From: Steve London <n2icarrl at gmail.com>
To: amps <amps at contesting.com>
Sent: Sun, Jan 20, 2019 4:06 pm
Subject: [Amps] SB-220 tick,tick,tick

I have an SB-220, of unknown lineage.

While using it, I noticed that on receive, listening on my receiver, I was 
hearing a strong tick, tick, tick sound, about 3 ticks per second. With a little 
experimentation, I noticed the tick rate was higher in the SSB position than the 
CW position. At audio frequencies, I localized the source to the HV area of the 
amp. My guess would be filter capacitors, rectifiers or equalizing resistors. A 
few more data points - the equalizing resistors are not the original - they are 
100K, rather than the original 30K. The electrolytics are Nichicon 200uF, 450 
WV, 85 degree C. That's probably not original, either. I don't see any cracked 
resistors. Best course of action ? Replace the electrolytics ?

73,
Steve, N2IC
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