Thanks, Steve

So it never was possible to hear both sides of the conversation on one
freq., even back in the analog only days?

thx

bob



Steve Silverwood wrote:
In article . net,
says...
Technically, exactly what is going on to prevent 2 sides of the call?

Aside from the issues of being in range of the remote unit, the
problem is that a mobile phone call operates on two frequencies.
This is necessary so that it works like a regular phone call, with
the party on one side being able to interrupt and the party on the
other side able to hear the interruption even though (s)he is still
talking. That's called full-duplex operation. With regular two-way
radio, you both operate on the same frequency and only one can
transmit at a time. The other party has to wait until the first
person has stopped transmitting in order to be able to be heard by
that person.

In full-duplex, each side of the conversation has to be on a different
frequency. You can't transmit and receive on the same frequency at
the same time on the same antenna -- just doesn't work. The minute
you transmitted, you'd be jamming yourself.