[Hallicrafters] SX-42 alignment - msg. to Al Parker

[Waldo Magnuson]

Hi Al,
    I'm rapidly getting totally frustrated with the SX-42 alignment.
    I first replaced C48 with a new silver mica of the same value (470 
pf).  No changes to speak of.  Both the old and new caps measured about 
the same value (I have a PACO and a Heathkit cap. tester and check one 
against the other).  I couldn't measure any leakage.
    I next substituted a 330 pf in place for C48.  I could still not 
tune to 1500 kc., 600 kc still tunes with the slug about 1 turn in.  
With the dial set at 1500 kc it takes an osc. setting of from 1200 to 
1380 kc to get any modulation output at the speaker terminals.  It's 
like C48 and C47 are being swamped by some other capacitance.  I 
monitor osc. freq. with a HP freq. meter so I am confident of the 
frequencies.
    I removed and inspected the slug of S-36 and it looks perfect.
    However someone (in the past) has replaced the cathode bypass cap. 
C38 with a 510 pf instead of a .01 uf.  It's tied to pin 4 of 7F8 
mixer.  I don't see how this could change the tuning of T23 but I'll 
change it - very tough to get at.
    Al, I really appreciate your thinking about my 42 and the help.  
Thanks.
Skip Magnuson