Re: [time-nuts] HP 5065 Rb update

[ed breya]

If the only problem is that you're at the resolution limit of the pot, 
you may be able to slightly modify the circuit, reducing the pot's 
effect, but also reducing the total adjustment range. I don't recall 
what the circuit looks like, but from the discussion I'm guessing it's 
like a 10 kilohm or so ten-turn WW with a kilodial on it, and it adds 
some adjustable current to the C-field network. The few k ohm range pots 
have set-ability that's near the small tick dial resolution. If the pot 
is quite low resistance, like less than 2 k, it can be much worse, due 
to the larger resistance wire - the wiper can only interpolate so much 
between the discrete wire turns, so the net value has more ripple with 
rotation. If the pot is in the few k region, you can gain quite a bit of 
actual resolution by upping it to say 50 or 100 k, but of course the 
rest of the circuit would have to be adapted.

Ed
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