I sold the plans in the 80's for $95.00 in the Gear and Mart. Paid for a bass boat.

Have since lost it but it's real easy to do in the shop. Their are some 100 ohm resisters in line with the CO circuits, easy to see when you look, on some boards the one by line 6 was labeled MOH. Just put a call on hold Line 1 and play with it. When you find out where it goes the rest are looped. There is no cross over, always worked fine for us. You can install a plug in the KSU or steal the VS.


Did this for Merlin 206/410/820 also. MOH, Paging
and Nite ring were just wire wrapping pins on the back plane. Nothing in those $400.00 boxes.

Same with that modular SW Bell system, topped at 616. Had a MOH cartg.