--- Dave <[EMAIL PROTECTED]> wrote: > > I use a couple of EF Johnson Challenger 71xx UHF > mobile radios for > the RX and TX side of one of my repeaters. Obviously > there is no COR. > A makeshift COR signal is the busy LED which works > to a point. The > busy LED lights up whenever there is ANY AND ALL > signals on the > frequency regardless of the PL tone. A static crash, > the noise floor > raising, a DX repeater, etc... it will trigger the > transmit on the > repeater, but the audio will not pass because that > is filtered by the > call guard (PL ). What I need to do is I need to > grab the signal from > the squelch gate trigger to make a true COR. > > However, directly taping to the trigger point with > the controller > loads down the whole thing and nothing is received. > I've tried using > a radio shack mps2222a transistor to make a > transistor switch and > still, it loads it down. I'm thinking now of using a > quad buffer/line > driver or something like that, but thats going to > use a lot of space. > I'd prefer to just use a transistor or something. > Something that I > can solder flat to the PC board and not have to run > a pile of wires > and add a circuit board. > > Does anyone have any ideas --- know of any > transistors that could be > used that will not load down the gate/squelch? I > need something that > is almost transparrent to the gate trigger. > > Thanks > > Dave > N9NLU >
It's hard to say exactly what you need without knowing some voltages, etc. What is the voltage at that point, squelched and unsquelched? When you installed the transistor, did you use a series resistor to the base of 100K or greater? This is an easy problem to solve, you just need to get the right values of parts. Joe __________________________________ Do you Yahoo!? Yahoo! Finance Tax Center - File online. File on time. http://taxes.yahoo.com/filing.html 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/
