So the printer is running open even with a good/checked loop supply. The machine is an M28ASR. Here is a picture of the LESU in it (I don’t know which version this is).

https://w2hx.com/x/TTY/ASR%20Pix/20220103_214634.jpg

You can see in this picture, the external loop is connected to the L J jack. I wonder if it was supposed to be in this jack. I can’t recall the definitions (L J is probably loop jack?). Unfortunately I don’t have any pictures of this from the last time it was running.

I also tried the LINE/TEST switch here:

https://w2hx.com/x/TTY/ASR%20Pix/20220103_214712.jpg

the red light lit up but the printer was still running open. I also confirmed, no voltage to any of the 4 selector magnet contacts.

I am hoping this is something simple. Wrong jack, open fuse, etc.

Any suggestions welcome.

73 Eugene W2HX

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