[Amps] 6146 AM Modulation

Bill Turner dezrat at outlook.com
Tue Sep 16 13:24:23 EDT 2014


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On Tue, 16 Sep 2014 08:35:55 -0700, wcw wrote:

>  Anyone know the answer?  

REPLY:

It's been a long time, but in the old days we modulated a 6146 screen
100%.  The easy way to do this was to NOT use a separate screen
supply, but rather supply the screen through a dropping resistor and
tie the supply end of the dropping resistor to the hot side of the
modulation transformer. Works great. 

If you use a separate screen supply., it becomes trickier. You would
need a separate modulation transformer just for the screen. It could
be done but I don't see the point. 

Also, do not use a very large screen bypass capacitor or the
modulation will be bypassed too. About .01 uF is big enough. Guess how
I found this out.  :-)

73, Bill W6WRT


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