I am not familiar with I Telex workings but a couple of hints that might help.
Both 32 and 33 TTY's have power applied to the SMD card when plugged into AC. Even in OFF mode.
32 Telex are normally 60 MA, not 20.
Its 33's that use 20 MA most times although its strapable to 60 MA and also Half Duplex. Rarely see that configuration.
Using a 32 Telex on RTTY its always in Line Mode and the TU turns on the motor so that is one application that can be left plugged into the TU AC long as the TU is not left on.
Testing a 32 Telex can be done with a 9 volt batt briefly.
With the 32 plugged into AC and running open (chattering), apply the batt to the Line cord. It will either shut down the Telex or keeping running with the loop closed. Reverse leads for the opposite condition.
73,
Wayne
KB1FDW