[GreenKeys] M28 using 20ma

[Steve Garrison]

To change the machine from 60ma to 20ma, on my machines, I would make a couple of wiring changes on the "A" terminal block in the LESU.  That is where the wiring from the "C" block makes it's transition to the connector that plugs into the typing unit.  If memory serves me, and lots of times it fails me, that is annotated as the "R" plug on the schematic of the wiring of a M28.  I could be wrong about the "R" but I'm right on about the "A."  On all my machines so far anyway.  Now if yours has been modified multiple times in the past, all of this might not be of any use in your case.  It should however match what you would find on a KSR or ASR schematic.

I could possibly be prodded into sharing a home made schematic that shows just this portion of the selector  magnet wiring from the "C" block to the "A" block and then on to the "R" plug.

This is how I have done several KSRs and I'm currently starting on an ASR, so I know the Reperf is going to have to be fit into the picture.

The thought just occurred to me, if you had the line relay, couldn't you run the relay windings with the 20ma loop and use the internal 60ma loop for the mags?  Providing of course your LESU has its own 60ma supply.


Steve G./N4TTY