View Single Post
  #1   Report Post  
Old November 12th 09, 04:35 AM posted to rec.radio.amateur.boatanchors
tchrme tchrme is offline
external usenet poster
 
First recorded activity by RadioBanter: Sep 2006
Posts: 25
Default Help needed with Halli SX 100 repair

I need tjhe wisdom of the list as this one has me totally stumped. A
week ago I posted about static crashes on this rcvr. The collective
advice was to check out the stages by removing tubes and then replace
the micas (which are discrete components on this rcvr) in the IF cans.
Well, the first tube that made a difference by removal was the 50.75
KC IF amp (6C4 V13) on the 2nd converter IF chassis so...I bit the
bullet and pulled the subchassis. Easier said than done on this rcvr.
I replaced the micas associated with T3, T4, and T9 the cans on the
subchassis. Still had static crashes...so I replaced all the IF micas
in the other cans while I was at it. Aligned it and sensitivity is
great but still static crashes. I thought maybe the C31 mica which
carries the signal out of the subchassis to V13. Tried subbing a cap
in and same result. The funny thing is that when I put my signal
tracer on V4 or T2 which is the 1st IF amp, I can hear the crashes,
but removing the V4 tube doesn't have an effect. Also removing the
tubes V5 and V12 on the subchassis doesn't stop the crashes. Several
questions. Could the static crashes be back feeding from the
subchassis to T2 or is the problem in that stage? Besides micas what
other component failures should I be looking for? Can a bad tubes
cause it? Thanks in advance for help. Mike KF6KXG