#636 key assembly

[Babybearjs]

  well, here's something that I'm not familiar with... as you all know, I won a red 564 on E-Bay and last light I went to test it... it tested bad... it wouldn't dial out and I was getting an impedance hum on the lines, the A-Lead was not breaking when the phone was hung up and I was getting a faint dial tone through the 5th line when all stations were off...  so, I went ahead and disconnected the station cord and pulled the 636 key assembly. I wired the phone up as a single line phone and all the problems went away. the phone rang OK (after having to re solder the coil with new wiring) the phone picked up and dialed out fine... So... I went ahead and put the 636 in a small container of rubbing alcohol and swished it around to clean it... let it dry out and then proceeded to reassemble the phone. upon testing it again, the problems persisted... it won't dial out and the impedance hum is still noticeable. the a_lead control works OK, but still acts like it has issues. I wired only the first 3 pairs of cord to test line 1 and the phone won't dial out, yet it hangs up fine. has anyone ever serviced these 636 key assemblies? what kind of test other than continuity can I perform on it to find the problem? or is it just easier to replace the unit?

[Key2871]

As far as servicing I've cleaned and adjusted contacts.
I've had issues with those keys before and found for the most part it was either dirty and out of adjustment, or the foam strips that sandwitch between the key switch them selves.
Now cleaning it was a good idea, alcohol isn't recomended.
It's just too strong a solvent, and create more problems than it solves, in this case. It can and has destroyed the foam sandwitch layers. And that's not good, because you you need those to insulate the switches that all run in line.

So, check that the hold button through line 5 are all clean contacts, check gap adjustment. And also check for cross grounding or shorts between other switch contacts.
It's tedious but if you can save that key, it's nessary.

But look closely at the insulation between the layers, make sure it's not turned gummy or something like that because of the alcohol dip.
You can try connecting one to each other switch for noise or crackling.

That should help you get to the bottom of any issues.

If you should find you need a new key, send me a pm.
At one time I had tons of spare parts for these sets, and I'll check what I have.

[Babybearjs]

Ken, what do you think would cause the dial not to work right? this is really weird because if I bypass the 636 and wire the phone as a single line, it works fine... I can't understand why this is happening... have you ever run into this issue? how hard is it to get a rotary dial to work? its only 4 wires?