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IBM Three wire to Two wire circuit


Registered User
Jul 12, 2007
I didn't get any help on my odd 2 wire IBM problem, (I couldn't figure it out either), IBM - Need help trouble shooting a 2 wire IBM / Simplex system. so I am going to try a work around.

I am making a three wire to two wire converter. See drawing. The K1 relay is large and slower then the reversing relay and serves as a time delay so a pulse doesn't get out before the contacts can transfer. Any thoughts? Better circuit?

3 to 2.jpg

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