Sam Goldwasser wrote:
Adam writes:


Hi all!

This might be a long shot... but here goes.

I have an old, 1941 Western Electric Model 302 Telephone. This is a
'real' phone, and has always continued to work flawlessly... until....

We took the phone apart to clean and polish the case, and install new
cords. I had to remove the dial and the hookswitch. New cords (cloth
wrapped of course!) were installed and everything was put back
together exactly as it was.

We have a wiring diagram for it, everything is in the correct
place. Here are its symptoms:
1. When listening with the phone off the hook, you can hear the line
noise, but no dial tone
2. slight motion of the pulse dial gives a momentary dialtone, which
then disappears
3. the phone rings properly, but will not answer when lifted off the hook.

The wiring diagram from Western Electric indicates that one of the two
clapper switches in the hook switch assembly "makes last" but it does
not give any specifications-- should there be a delay between the
closure of one part and then the other? I can't really imagine the
phone company in 1941 detecting an 80ms delay between two switches?

I've really been at wits end because nothing seems to have changed
except that the phone wont trigger a dial tone. My previous
understanding was that the CO (central office) detected a closed
circuit through the hook switch and that was what triggered the dial
tone. I've checked all contacts in both the hook switch and dial and
they all connect and disconnect cleanly.


Does the resistance into the phone go low when it's off-hook?

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Just working from memory--distant memory--and referring to symptom #2
above, it sounds like the issue may be in the dial mechanism. Given
that the dial makes/breaks the line connection in order to function, and
further given that a dial tone can be obtained, however briefly, by
moving it...it seems to me to be a contact issue within the dial itself.

I could be wrong, but....

jK