[Milsurplus] TBY

[Hue Miller]

I just took a millisecond look inside a TBY.
I cannot put aside time for hobby tinkering for
many months still, but from what i observed:
the coils rotate on a turret type thing, contacts
on the coil press against pick-up fingers. The
tuning coil is an autotransformer, one winding 
only. I think it would be possible to: locate the
two taps that go to the transmitter tube taps.
Slide a bit of paper or plastic or mica sheet
between these two fingers and the coil points
that meet them. On the solder lugs to the same
two fingers, tack solder a 3rd overtone crystal
across. Don't touch that dial, i mean bandswitch,
when you're using this mickeymouse setup.
Transmitter tuning will be MUCH different. Instead
of a continuously running oscillator whose output
varies as you do the antenna tuning, the "TUNING"
control will now swing the oscillator suddenly into
and out of oscillation as you swing across the
crystal's resonant frequency.  This is all THEORETICAL
and may not be worth beans but it's a matter of 
a few minutes to undue it and have the experiment
be practically undetectable thereafter. Who will go
for it? The object, of course, is to make the TBY's
free running power oscillator inter-operable with 
superhet receivers with a non-wide bandpass.
-Hue Miller