[AMRadio] VFO vs XTAL

Jim Wilhite w5jo at brightok.net
Wed Oct 17 22:20:30 EDT 2007

If I am not mistaken the Johnson 122 VFO has a coupling cap in it to the 
output.  I really don't remember for sure.  If it doesn't use a 75 pf. 
to the grid of the buffer.

If the VFO has a coupling cap, tie the VFO output directly to the grid 
of the buffer and see what happens.  If you don't have enough then, move 
back to the grid of the Osc.  Just be careful of driving the Osc to 


>I ran it through a small capacitor before the grid of the 828 buffer. 
> appreciate the info Jim and Geoff on the output of the 122.  I thought 
> it
> should be plenty hot to do anything I wanted.  I guess I'd better go 
> back to
> crystal control and not take on another project of repairing the vfo 
> at this
> time.  It was just for a test anyway.  I am supposed to get about 100 
> ma pa
> grid current and I'm only able to muster up about 65 ma.  However, I 
> am
> getting the full 250 - 275 watts of RF out.  I just need to level it 
> out a
> bit.
> Thanks guys...
> Rick

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