All, I am trying to help a local group with a remote TX/RX site they have which is remoted to their office with a leased phone line and some Motorola tone remote equipment. I know the radio end has a Motorola L3276A adapter, and the office end has a "telephone style" handset (don't have the model number).
As of last week, this system will no longer transmit. It still receives fine, but will not activate the PTT on the remote radio, or at least there is no transmitted signal. The fact that is receives tells me that at least the line is intact. I have not yet been to the remote site (several miles away) to look at the radio, but I want to know a little more about this tone remote system before I go: 1) Can I plug a regular telephone into the pair to monitor the signaling? 2) How is the signaling done for TX and RX on the 2 wires? 1950Hz tone or something similar? 3) What should I hear on the line when the PTT on the handset is pressed? 4) Is there a way to passively monitor the leased line audio for the signaling from either end with my HP 8920A service monitor? I don't fully understand the concept of balanced lines, and I don't want to damage any of the equipment by connecting something I shouldn't to it. Any help would be appreciated! Dave Cameron - VE7LTD IRLP System Designer
