Hello -
If anyone has a 601A KSU, I was wondering if you could do me a favor.
I get hum when hooking a telephone across AB/AG.
However, if I hook the phone across the T/R terminals of the intercom, there is no hum.
I understand that normally you have AB for filtered voice, and BB for relays, etc - but the 601 only has AB/AG.
Having said that, the manual says that AB/AG can be used for voice, as well as relays, etc.
Ed is shipping me a power supply to see if that's my problem. However, I'd hate to take the chance that there is something wrong with my KSU that causes power supplies to go bad.
I've also replaced every component on the power supply board that I think could contribute to hum (capacitors and diodes). All that's left is the transformer, and from what I'm guessing a couple voltage regulators. (The voltage holds steady on all AC and DC outputs).
Of course, I'm by no means an electronics wizard; pretty much a parts swapper/hack in that area.
Anyway, if somebody has a 601 in use that you could hook a butt set or the tip and ring of a telephone across AB/AG on, and see if you get hum, I'd appreciate it very much.
Thanks
Matt
