CDR700 with CDM750's Repeater and duplexer

[sullijwiii]

I am attempting to program the CDR700. I got it setup to repeat on the same frequency but got a constant tone from the TX radio every time the RX radio received. I changed to a different TX frequency and no more tone. I still want it to re-transmit on the same freq. Somewhere in the middle of changing settings to find out why I got the tone I could no longer receive on the RX radio except if I unsquelched it (by holding P2 button for 1.5 sec). I swapped the radios, no change. I removed the repeater and duplexer and connected the radio directly to an antenna, still no change. Something is keeping the radio from breaking squelch unless I manually do it. I get no light on the RX radio when it receives, even when it is unsquelched. I have taken all the repeater settings out and still no change. I thought I had saved the default cps but apparently I didn't. I have been through every setting. I am testing on an unused channel (464.475). As I had said I swapped radios to see if it was a receive issue as the othr radio was set for TX only but both radios do the same thing, no receive, (unless I unsquelch) and no RX light at all.

Also a side question about this setup - the duplexer has a high and a low port, the CDR500/700 manual does not label these ports so I had to assume by the pictures that I connected them correctly. Which radio RX or TX, goes to the high and low ports?

 

[kayn1n32008]

Wirelessly posted (Mozilla/5.0 (BlackBerry; U; BlackBerry 9780; en-US) AppleWebKit/534.8+ (KHTML, like Gecko) Version/6.0.0.600 Mobile Safari/534.8+)

Repeaters do not repeat on the same frequency. The repeater MUST use seperate frequencies. One will be 'higher' than the other. The frequency that is 'higher' than the other goes to the high pass side and the lower frequency goes to the low pass side. The duplexer must also be tuned to the frequencies you are using as well. If not it will be deaf and can burn ouit the transmitter

 

[sullijwiii]

Thank you very much. I was hoping maybe that because of the 75db isolation in the duplexer it would work but I knew better.

Any idea why after chaning settings on the 750 why I can't break squelch but when I manually unsquelch I can hear my self but get no receive light on the radio?

 

[kayn1n32008]

Wirelessly posted (Mozilla/5.0 (BlackBerry; U; BlackBerry 9780; en-US) AppleWebKit/534.8+ (KHTML, like Gecko) Version/6.0.0.600 Mobile Safari/534.8+)

No I can't help with the squelch thing, make sure PL/DPL matches what your transmitting, and get it set for a split pair, preferably 5MHz difference between Tx/Rx. Also get the duplexer tuned for the pair. The higher of the two frequencies goes to the highpass port, the lower to the lowpass port antenna in the antenna port. First apply for a license, Once you know the pair you are going to be using, get the duplexer tuned(VERY IMPORTANT) if not you WILL burn out the PA in the transmit radio and the reciever WILL be deaf. After all that is out of the way program the radios THEN after everything is tuned and hokked up, do a function test before you install the repeater. Also use double shielded coax for jumpersbetween radios and duplexer and hardline for the run from the duplexer to the antenna. Anything less is going to create problems and frustration for you. Absolutly no LMR400 coax.