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I remember seeing an old telephone switching system from the 20's and I think it was 48vdc. Uncertain though.
by m463 2y ago
I remember seeing an old telephone switching system from the 20's and I think it was 48vdc. Uncertain though.
- ttyprintk 2y agoYeah, would have been 48 vdc for line operations, 60 and up AC for the ring.