I would also be interested in a set of the 50 baud gears if they're available. I also have a TT4C machine which only has 45.5 and 75 baud gears. I have tried to adjust the motor speed to change the machine speed up to 50 baud from 45 baud but I found the governor didn't have enough range. Attached is a photo of my setup.
I will check our stock at the AWA (Antique Wireless Association -
not to be confused with Amalgamated Wireless Australia) Museum
when I am there on Tuesday. I know I have extra gears, but don't
know offhand if there are any 404 opm gears.
All mechanical TTY machines can receive over a +/- 10% speed
variation, using the Range Control to adjust when the selector
magnet reads the data. So your TT-4 can copy 66wpm with the 368
opm gears (just turn the Range control down to about 20), but of
course you will need the 404 opm gears to transmit 66 wpm.
You could also try increasing the motor speed by about 10% while
still using the 368 opm gears. I don't know how increased speed
would affect the life of the motor or brushes. But since the unit
was designed to work 24/7, and as long as you only use it a few
hours a day, I wouldn't think it would affect its life
significantly.
Good luck & have fun,
Duncan Brown, K2OEQ
USASA 31J30
Antique Wireless Association
Communication Technologies Museum
Asst. Curator, Commercial Equipment
(also chief TTY op & repairman)
I need a gearset for a TT-4/TG to operate at 404 OPM / 66WPM /
50 baud. I am happy to exchange a 368.1 OPM / 60 WPM / 45.45
baud set and a 600 OPM / 100 WPM set. The TT-4 manual states
that the 368.1 OPM set is normally fitted and the 404 OPM set is
held inside the machine. My machine is fitted with a 368.1 OPM
set holds a 600 OPM set.
I am located in Adelaide Australia and am happy to pay parcel
post both ways.