[AMRadio] VFO vs XTAL

Geoff/W5OMR ars.w5omr at gmail.com
Wed Oct 17 21:10:44 EDT 2007

Rick Brashear wrote:
> It doesn't matter as far as the operation is concerned IF there is enough
> drive.  I'm not getting sufficient drive from either.  However, I am getting
> much more drive from the internal crystal oscillator than from the Viking
> VFO and I found that strange.  I would have thought the VFO would put out
> more RF than the xtal oscillator.

What rig is this in, Rick?  MAn, the Viking 122 VFO, at least on the 
Viking II, has -plenty- of drive! 

I keep my grid drive control down, on 80m, around 2.5 or 3 on the knob.  
That gives me around 7.5mA of grid drive for the pair of 6146's (yeah, 
Ellen - I've been meaning to send you that correction - Johnson says a 
single 6146 needs no more than 2.5mA of grid drive, the pair in the 
Viking II needs 7.5mA of grid drive, and I'm guessing (someone tell me 
for sure) that the Valiant, with it's (3) 6146's needs around 10mA of 
grid drive?) and if I crank the knob up to around 5 or 6, then I've in 
excess of 10mA of grid drive on the pair of 6146's.

Driving your AM Rig without a scope, 
is like driving your car at night, without headlights. (K4KYV)

73 = Best Regards,

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