[GreenKeys] RS232-Current loop converter troubleshooting

[Sarah Autumn]

Hi all,

I finally got around to building the loop to serial converter that everyone
knows and loves (http://www.aetherltd.com/connecting.html). It worked fine
at first, but now I'm getting this weird behavior.

When there is no teletype connected, on the pins for the selector magnet
(J1 5&6) have voltage. When I connect the teletype to the pins, the voltage
drops to almost nothing, and the magnet doesn't operate. If I remove the
teletype from pins 5&6, the voltage jumps back up to 100V. When I hook the
teletype directly to my loop supply, it runs fine.

I have also tried 2 different power supplies: One is an acoustic coupler
modem used for the deaf, and another is a REC-50.

I have checked the values of all my resistors and capacitors. What simple,
easy thing am I doing wrong?
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