Have you checked the repeater for desense without the antenna installed? As in
most commercial repeaters they are usually designed for larger spacing than 600
kHz. Check it without the antenna and all open ports terminated with a 50 ohm
termination. Then add the antenna and look at the difference. I have had
problems where I had to split the transmit and receive to two different
antennas and split the duplexers accordingly.
I also chased this down once to a cheap right angle connector, the manufacturer
used a spring to make the turn and it made a neat detector!..Jim
