A question on Communications

Is your antenna a ground plane independent antenna ? If not that could explain your symptons.

Hi Richard

Such a senario is generally only possible when there is local interference
(engine noise?) at the receiving location. Resulting in a sub-standard setup in the other car.

First 2 things

F. M. communications has a sharp threshold at which signals go from poor to clear.

The direction of strongest signal in these type systems is normally in the direction of most metal.
I.E. If your antenna is on front Bullbar , you will have a stronger signal towards the rear of car.

Given the above - its possible your signal was strong enough to overcome the limiting noise when other car was behind , but not when it was if front.

Your antenna type would make some , but limited difference.

These effects are a reason I use a centre of roof mounted 1/4 whip which has
better omni directional characteristics.

check all your antenna connections; it is quiet possible you have a loose connection or dry solder joint on a plug or cable from the radio to the antenna. Often under these circumstances you can recieve ok, but the connection breaks down under power (e.g. transmit). Also check to see if you have a break in your antenna.
regards

Richard I had exactly the same problem and was asking around etc and considered replacing the antenna etc etc etc.....when someone ask me if the connection AT THE antenna was still good......so when I got home and grabbed the cable at the bottom where it goes up into the antenna and guess what.....it just pulled straight out....it had broken off because of all the flexing over time and travel.
So you could receive OK but it would not send.

So I pulled it apart and remade the connection and no more trouble....how easy was that, lol.

The antenna comes apart really easy and it is so simple to remake the connection again after you strip the cable back ( allow about 50 mm) and NO soldering....it just wraps around a washer and is sandwiched in there. Just clear the shielding back enough so as not to touch the the core wire, the shield or screen is not connected at the antenna end but at the radio end.

.