[AMRadio] Still more SP-600

Rick Brashear rickbras at airmail.net
Thu Jan 11 22:46:58 EST 2007

I tried to post this to the Hammarlund list, but it is being held for 
the administrator's approval, whatever that means.  So, I'll post it 
here too in hopes someone will have mercy on me.

I am still having trouble with aligning the SP-600/JX-17.  I am 
obviously overlooking something, but...  Here's where I am.  Tubes have 
been replaced with known good ones.  I've tried several 6C4's with the 
same result.  I have replaced all paper capacitors in the rf/oscillator 
strip.  All resistance's and all other capacitors in the strip he been 
tested and are well within tolerance.  The RF chokes are good.  In fact, 
all components in this section have tested good or have been replaced 
with good parts.  The capacitors in all oscillator modules in the turret 
have been thoroughly checked, replacing any paper capacitors or out of 
tolerance parts.  The voltages check well within tolerance as per the 
manual.  The IF alignment has been made.  The problem is the oscillator 
alignment is not wide enough to stretch the entire band on any of the 
bands.  If I get it right on the bottom it's off at the top and visa 
versa.  Same problem I have had since I began this project.  Am I 
missing some obscure adjustment?  I've performed the alignment procedure 
exactly as described in the manual.

Since everything is right (and I have checked it all twice and some of 
it more than that) it must be me, but I can't find out where I'm going 
wrong.  Any and all suggestions will be greatly appreciated.


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