[Johnson] Pacemaker Problem

[Edward B Richards]

David;

When I saw your subject line, I got a start. I thought it was from my
doctor, at first. I am scheduled to get my pacemaker replaced in a couple
of weeks. Not the same thing!

73,  Ed  K6UUZ

Seeing your subjec 
On Fri, 08 Jan 2010 10:18:22 -0500 "David C. Hallam"
<dhallam at rapidsys.com> writes:
> I have run into a problem in the alignment of my restoration project 
> 
> Pacemaker.  The two carrier crystal oscillator signals for the 
> balanced 
> modulator are taken from a 12BH7 cathode follower at a common point. 
> 
> The two signals go a switch.  One to a front wafer and the other to 
> a 
> rear wafer.  The front wafer has switched capacitors for each band 
> and 
> the rear wafer has switched slug tuned coils to get the 90 degree 
> phase 
> shift.  The Pacemaker uses a different carrier oscillator frequency 
> for 
> each band.
> 
> Then each signal is connected to the balanced modulator tubes.  The 
> wave 
> forms on all bands from the front wafer with the capacitors look 
> good on 
> the scope.  The ones from the rear wafer are distorted for the 80M 
> and 
> 40M bands.  10M and 15M are good and 20M is probably OK.  The 
> distortion 
> shows up as a knee on the first 90 degrees of the sine wave.  So far 
> no 
> amount of twiddling with the oscillator output voltage or the phase 
> 
> shift adjustment has cleared this up.
> 
> Any ideas?
> 
> David
> KW4DH
> -- 
> 
> I predict future happiness for Americans if they can prevent the
> government from wasting the labors of the people under the pretense 
> of
> taking care of them.
> Thomas Jefferson
> 
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