Originally posted by Silversam:
Matt -
Do you have one or two sources of -24VDC on that beast? If you have two hook one up for A and the other for B.
Also - lift all the wiring off the power supply -24v, then take a butt set and go a cross it. If it still hums coming out of the supply, then that's it. If it doesn't, start attaching the connections one at a time and see which one puts on the hum. Trace that back and see - might be a defective 400 card or......?
Also that ICM I sent out will work Tone or Rotary - so if you dig up some old sets, it'll still work.
Sam
Sam -
Pretty sure there is just one 24v output. See my PM for PS specs.
I'm thinking I have a ground issue or something. AG is tied to the power supply grounding screw as per instructions, and basically every ground (AG, LG, etc) is really the same point now. I tried disconnecting all keysets (2) and swapped in a third one (an ITT) in favor of the 2 WE keysets - same buzz. Then I disconnected the lamp feeds to the intercom, and the 18v station signal input... same buzz. My next step will be to disconnect everything from AB and AG; possibly everything from the entire KSU, and see if I still have a buzz on AB/AG...... if not, then I'm guessing it's the intercom putting out the buzz, since it feeds tip and ring to the keysets.
It's really not that much of an annoyance...... but it would be nice if it were completely silent.
I do have an ITT rotary, so it's great to know it will work with both!
Thanks Much!
Matt
