[Hammarlund] Accuracy

[Roy Morgan]

At 11:43 PM 1/12/2007, you wrote:

>In between the top and bottom, all bets are off. The big variable 
>capacitor isn't calibrated any more after 30 years. Moreover, you and I 
>can't align it. It requires a custom jig that compares one section to the 
>next and measures the capacitance. We had an email a few years ago from a 
>lady that actually aligned these capacitors for Hammarlund.

Capacitor Nuts,

I would really like to read that email if anyone can find it.

"Knifing" a tuning cap is a skill, but it seems to me it's not rocket 
science.  Having little experience in it, I won't speculate on how it's done.)

One trick however, is to align the band tracking a quarter of the way in 
from the band edges. This will reduce errors in the middle at the expense 
of hopefully modest errors at the ends.

>One of these days, maybe I'll sit down with a precision capacitance bridge 
>and try my hand at adjusting it, but only if I have a lot of time to kill . . .

Hooray for the precision cap bridges (I have more than one GR bridge 
here).  But if the goal is to make a radio track right, I'd suggest using 
the radio itself as part of the experiment.

Roy



- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing
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