[R-390] R-390 alignment

[Gord Hayward]

One thing to note with the balanced input is that one side has a 
variable alignment cap to ground and the other a fixed cap.  You
need to make sure that if you ground one side and feed the other, you 
feed the side with the variable cap.  The ground shorts
the fixed cap.  I did the balance adjustment to set these, but I wonder 
if running with an unbalanced input  I should just peak
the response with the variable cap to match the input better.  What do 
you think?

On a similar topic, I get some crackle when I adjust the antenna trim. 
 I think the rotor contact is a bit dirty but getting into the
box will be a major pain.  I plan to try some deoxit on the shaft when I 
next open the case, but is there any other accumulated
lore on this subject.

73 de Gord, VE3EOS.

-- 

Gordon L. Hayward, Ph.D., P.Eng.,
Associate Professor, Biological Engineering,
School of Engineering, University of Guelph,
Guelph, Ontaro, N1G 2W1.