[Milsurplus] UGC-74 Teleprinter

[Ray Fantini]

Next problem, the UGC-74 A teleprinter. Would like to use this UGC-74 A printer in the field with my GRC-106, the teleprinter has the usual roller rot and I did remove all the melted roller residue and before I spend any more time on this wanted to see if it works. Long story short is it has the unregulated +28 volt supply, the +5 and +/- 8 volt supplies are good but the MPU +5/12 volt supply is dead. Only puts out a volt or two. Also, the drum motor never spins up, but think that's related to no control signal because the MPU is dead.
Anyone have any idea on what may be a common issue on the power supply card for this printer? Or a spare power supply card for an A model?
Before anyone asks why I am wasting my time with an A model and all its roller problems let me say I wanted an A instead of a B or C because unlike the later versions of this teleprinter the A uses a regular typewriter ribbon and have had C versions before and they all were subject to needing a stupid cartridge that never works. If I can get the electronics sorted will turn to how to tackle the missing roller.
I know that shipping a 100 pound TTY is a bit of a problem but think sending just the power supply card would be easy. Or if anyone knows of an interlock or some other thing I am missing please help. I looked at the card briefly and saw that at least one of the filter capacitors (C3) is open and would assume that maybe more are also at fault but wanted to see if I can find entire card to swap first.

Ray F/KA3EKH

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