Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!accuvax.nwu.edu!nucsrl!telecom-request From: John Higdon Newsgroups: comp.dcom.telecom Subject: Re: Trying to Fix Old Phone Message-ID: <11628@accuvax.nwu.edu> Date: 1 Sep 90 18:01:03 GMT Sender: news@accuvax.nwu.edu Reply-To: John Higdon Organization: Green Hills and Cows Lines: 26 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 10, Issue 614, Message 8 of 9 Lord High Everything Else 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 !