Single Tube Modulator
Which Year One was that, Harold? Where I became a ham many years
back, there was a creative fellow in our club who designed a compact
AM transmitter using a couple 6146s, one for the RF PA and one for the
audio output. They were coupled not by a choke as in Heising, but by
a common audio output transformer, available back then much more
readily than a modulation transformer, and having the advantage that
the DC in the center-tapped winding was (nearly) balanced, avoiding
saturation effects in the transformer and allowing the use of a
relatively small transformer. I think Mitch designed that thing in
the mid 50's.
Cheers,
Tom
Hi Tom. Must have been around 1954, cause I'm sure it was after I came back
from Sunny Athens Greece. (SV0WX) I have the complete QST on disk, if you'd
like to peruse the article, I can go find it for you.
(Yes, and there was another one. Mobile Tube rig, winding up in a 10 Watt
2E26 I think, with something like a 25 Watt transistor audio amplifier for a
modulator. Part of THAT was rectified and used for the B+ for the rig. I
started on building that and then found a vibrator supply.)
Regards
W4ZCB
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