Greetings,
I am having a problem with a 440 repeater that I am putting
together. I started with a MVP custom that I converted to 70cm and
duplex modded. The radio tuned quite nicely on 443.800 tx and
448.800 rx. Tx and Rx well before the duplex mod. I made sure to
get Hi side LO xtal for my rx also. I installed the ICS Basic
controller and the COS is working, and ptt working great. But I
have a horrable feedback injection. I can turn down the audio on
the controller to its lowest setting and still have the feedback. I
can turn the radio's PA down to 500mw and the feedback goes away,
but there is still noise in the audio. When I turn the pa back up
or even to from 2-10w the noise is back even in the squelch tail.
If I disconnect the controller, my feedback goes away. I have also
directly connecting my rx audio to my tx audio and keying the
xmitter, and using my ht supplying an imput signal and get good
audio out at full power. But when I put the controller back in line
the feedback resumes. I also noticed waiving my hand over the
controller while the feedback is happening changes the frequency of
the feedback. Any ideas?
Thanks and 73 de Joe KB5VJY -- First repeater project not working
out!