Ok, I am learning a lot about how this is connected. For 15 years this ASR just worked, I never had to worry about it so I never had to learn about how it is wired up. I have a question for those of you who are familiar with this LESU.  I have a 60mA meter (newly crafted) that works great when I plug it into my external jack field for my ST-6. Reads about 55mA sounds good to me. I then plugged in the meter into the BJ, RJ and PJ expecting to see something. However I saw zero current and the act of inserting the plug (of the meter) into PJ caused the printer to run open (and I know my meter is not open!).  Also BJ showed zero bias which I don’t think is the case.

So I got to thinking. Maybe the plug on the meter isn’t “compatible” with these jacks on the LESU. I am using what I believe to be fairly standard TRS plugs and I am using the Tip and Ring for the loop. Can anyone tell me if, perchance, the jacks in the LESU are expecting something else, perhaps Tip and Sleeve? That could explain what I’m seeing? Anyone know?

https://w2hx.com/x/TTY/43A-1%20Test%20Meter/20221202_203627.jpg

73 Eugene W2HX
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