I have two crank phones paired, can hear self, but low/no volume to other phone?

[RB]

Been seein this a lot.
put two lb phones together, and can hear sidetone in each rec quite well.
but, they don't wanna talk to each other??
Or, one direction good, other, bad.
My phones are mostly liech, federal, WE, and a few odd balls.
Most play together fine, but a few just don't.
Question 1 : If I can hear myself in the rec, then the transmitter and rec must be working, right? or am I way off here?
Question 2 : Is it possible to have an impedance mis match thats so out of whack, as to prevent the audio from passing from one phone to the other?
Question 3 : Could the bells be killin the audio transfer from one to other?
I am so close to solving these last few issues. just need a few more brain cells to fill up...

[dsk]

Been seein this a lot.
put two lb phones together, and can hear sidetone in each rec quite well.
but, they don't wanna talk to each other??
Or, one direction good, other, bad.
My phones are mostly liech, federal, WE, and a few odd balls.
Most play together fine, but a few just don't.
Question 1 : If I can hear myself in the rec, then the transmitter and rec must be working, right? or am I way off here?
Question 2 : Is it possible to have an impedance mis match thats so out of whack, as to prevent the audio from passing from one phone to the other?
Question 3 : Could the bells be killin the audio transfer from one to other?
I am so close to solving these last few issues. just need a few more brain cells to fill up...

To question 1: Usually, yes.  What may go wrong? The common wire for transmitter and receiver may be broken, and you may still hear yourselves OK, but extremely faint in the other end.

To question 2: Never heard about that, and I do not believe it is possible.

To question 3: Nope, I have heard about systems with more than 10 ringers on the same LB line.

For testing out a LB phone, just connect a cb phone (without semiconductors) on the line, It shall ring when you crank the LB, and you may hear loud and clear whats spoken in to the LB phone..   A 9V battery and a resistor of 100-220 ohms in series putted across the line, and the CB phone should be heard in the LB phone. 

dsk

[RB]

Will try, thank you