Lord High Everything Else <geary@cis.ohio-state.edu> (08/31/90)
I have a telephone that I'm trying to fix. The dictionary
identifies it as a "300" model telephone. We last used it in 1976 and
it worked fine then. Now, when I plug it in I can dial out; it will
ring when we receive a call and I can answer the call and here the
other party's voice; but when I try to talk, it won't transmit my
voice. I've tried swapping the microphone element with a phone that
works, and I know that it is good, so the fault must be elsewhere in
the phone. I've looked inside and nothing obvious is broken, but,
while I can identify most of the individual components, I don't know
how they all work together.
Can anyone give me advice on fixing this telephone, or tell me
where to look for information?
| Mark Geary, Department of Computer and Information Science |
| The Ohio State University, 2036 Neil Ave., Columbus OH USA 43210-1277 |
| ...!{pyramid,killer}!cis.ohio-state.edu!geary (614) 292 - 0915 |
| geary@cis.ohio-state.edu or geary@tut.cis.ohio-state.edu |John Higdon <john@bovine.ati.com> (09/02/90)
Lord High Everything Else <geary@cis.ohio-state.edu> writes: > I have a telephone that I'm trying to fix. The dictionary > identifies it as a "300" model telephone. We last used it in 1976 and > it worked fine then. Now, when I plug it in I can dial out; it will > ring when we receive a call and I can answer the call and here the > other party's voice; but when I try to talk, it won't transmit my > voice. If you have cleared the transmitter itself, and the phone will seize the line when off-hook, then look for a short in the handset transmitter "pair". There are three wires going to the handset (vs four in a 500 series phone) and one of them is common to both receiver and transmitter. The other possiblity is a defective network. One of the neat things about a 300 set is that when you disconnect the transmitter (unscrew the cap and take it out), the network releases the line, but you can monitor perfectly through the receiver. If you remove the transmitter and the call stays up, then the transmitter circuit is shorted or something else is screwy. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@bovine.ati.com | San Jose, CA 95150 | M o o !