[R-390] R390A alignment question

[djed1 at aol.com]

The IF bandwidth of the R-390A is determined by the mechanical  filters.  
The only exception would be a case where the transformers have a  narrower 
bandwidth than the mechanical filter.  I expect this is the case  with the 16 
Kc filter.  So the only reason to go through the stagger tuning  process is 
to assure that the 16 Kc bandwidth is correct.  Most of us don't  bother 
because we don't use the 16 Kc much.  But if you want to do it up  right, I 
think you just have to offset the signal source to either side of 455,  then 
peak up alternate IF transformers.  I haven't done it, so I can't  offer an 
exact procedure.
Ed