[R-390] R-390A Cosmos EP adjustment

[Larry H]

Hi Dave,  There are a few docs on the 390 disk that talk about VFOs.  Mine
on the Cosmos is here in the Pearls menu:
https://www.r-390a.net/Pearls/PTO_Cosmos_Observations.pdf

I talk about adjusting the EP range by adjusting the capacitance.  In there
I added an 82 pf ntc 200 cap in series with one of the two 10 pf caps to
bring the existing EP coil into range.  That moved it about 5 kh, which in
your case would not be enough.  17 kh is a very large offset, even for a
Cosmos.  I'd recommend putting the EP coil back to original (so it can be
adjusted in the future) and adding a 60 pf  ntc 200 in series with one of
the 10 pf caps.

Although the drift on your Cosmos is good, it could be better, so I
suggested an ntc of 200.  You can play around with that if you want.  But,
you will not see the final drift offset until you reinstall it in the
390A.  It will be less in open air.

Regards, Larry