[Milsurplus] MAK Transmitter osc

[Hubert Miller]

Forgive me if I'm restating things obvious to the reader.
The oscillator circuit at these frequencies, the old "2 MHz marine band", are most assuredly NOT overtone type.

Other comment: I am a little surprised at the 100:2000 pF ratio in the oscillator. I suspect and think possibly
increasing the 2000 pF size will do the same effect as the gimmick, that is, increase feedback. I do not think
crystal capacity has anything at all to do with what you're experiencing. If either the 100 or the 2000 has some
problem, that would affect feedback level => oscillation. Crystal capacity will affect the exact working frequency
some, but not affect feedback.

I just now took a look at the TCH manual. It uses for these 2 Colpitts caps, 50 and 100 pF. Not exactly what I
expected to see.

I think the MAK has a large loading coil right inside the cabinet. That will develop massive RF voltage, with a
short antenna, and somehow that's getting back into the oscillator. Pretty hard to eliminate that.  IF the designer
had used an oscillator at ½ the frequency, it probably / maybe would have eliminated that.

Re the interesting pushpull oscillator circuit: I am thinking it will work with only one g - p added capacitor.
But power output is maximized when the g-p is somewhat more equal. I get this thinking from a military
VHF generator manual I read. It has a pushpull osc with trimmer caps from each plate to grid. The adjustment
procedure had you tweak them for maximum output. It wasn't a massive difference, though.
-Hue
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