[Collins] Collins TCS12 mods

[John Nicholson]

Hi Guys,
I use a Collins TCS12 in original condition on our AM nets, I get reports 
from time to time that it lacks audio.
Not surprising since the mic transformer feeds direct to the grids of the 
1625 modulators without any preamp.

Does anyone have or know where I can find any info on modifications I can 
make to increase the modulation level? I want to keep the transmitter as 
original as possible but have thought of removing one of the crystal 
sockets and adding a pre-amp stage.

73
John Nicholson
ZL1AUB
SPAM Librarian,
(Society for Preservation of Amplitude Modulation)