At 07:47 PM 6/1/05, you wrote: >I have a GE Mastr II repeater on 444.325 +. The repeater was originally a >VHF base station. I swapped out the RF modules, interfaced an outboard >controller, and the other things to make it play. Or so I thought. I am >using 2C ICOMS in the transmitter and receiver. The were redone by ICM. >The Rx was sent back for them to repair after it wouldn't stay on freq. I >got it back and thought all was ok. Earlier tonight, someone pointed out >that it seemed the off frequency. The Tx is fine but the rx seems to be >off. I haven't actually measure to see if it is but everbody sounds bad >getting into it. Even the ham that lives 1/4 mile away. I was discussing >this problem with another repeater owner here and he suggested maybe the >comp line between the ICOMs was still connected and causing problems. The >station originally had a 5C in the rx and an EC in the tx. Could this be >causing problems? If so, can someone point me to the easiest was to break >this connection? I don't have the complete manual here. I have tidbits of >it in PDF but not the complete station/repeater manual. > >Thanks > >Jamey Wright >KD4SIY >444.325 >Wilson Mtn/Oden Ridge, Al
How old are the crystals? If less than a year, I'd just put it back on channel, especially if it's less than 6 months... I've seen new crystals move as much as 6khz as they age the first 6 months. And it's not always the same direction. Strange as it seems, I once saw a crystal drift down 2khz, then up 3khz, then back down 2khz and it finally settled down there. See the article at <http://www.repeater-builder.com/ge/mastrII/m2icoms.html> and pop the covers off and compare the guts to the pictures. I've seen ECs and 5Cs with 2C covers and sold as 2Cs. Remember, a 2C element stands alone, only a 5C generates comp voltage, and only an EC receives it. If you are running true 2C elements the comp pin isn't even connected. In a station the comp pins on the elements in a chassis are connected together, and to nothing else - i.e. all the RX comp pins are tied together, and separately all the TX pins are tied together. A common mod is tying the comp lines of the two chassis together. I've been told that some GE stations came that way, but I've not seen one. In your case, I'd pull the both elements, put a DVM on the comp line of the TX chassis and check the voltage.It should be floating - an open circuit. Then plug the TX element back in. If the voltage changes, that's significant. Then do the same procedure to the RX chassis and element...If the voltage changes, that's significant. The above procedure should tell you something.... let us know. Mike Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
