[AMRadio] National PW Dial

D. Chester k4kyv at charter.net
Mon Mar 12 12:06:57 EST 2007

    >Does anyone have any information on getting a PW dial { 0 to 500 units) 
to directly correspond to 0 - 500 Khz. in a VFO circuit? I have the National 
 >"PW Condensor", a PW dial with a 155 pF. air variable. Thanks, Byron 

>It might be possible, by carefully pruning the coil, and adjusting the end 
>plates of the capacitor by bending them in and out.  It would depend on the 
>fixed >capacitors used in the tuned circuit.

Good luck.

It would probably be more trouble than it's worth, since the capacitor will 
need to be somewhere intermediate between straight-line frequency and 
straight-line capacitance, and which would be designed to work over a 
specific, limited range of maximum to  minimum frequencies.

Probably better to just do like National did with the HRO and NC-101 series: 
make up a tuning chart.

Don k4kyv

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