At 10/18/2007 10:52, you wrote: >Re: Need recommendation for small repeater controller > >How much work do you want the controller to take on? Most of the
For this application, just a single repeater - no remote bases. I do need DTMF control of the repeater (on/off) as well as a TOT that can also be disabled, & a courtesy beep. >smaller repeater controllers are pretty basic, many don't include >an input valid detect line for switched and controlled CTCSS Operation. > >A simple D-9 connector (aka db-9 to most of you) to an external >controller can make the MVP a much "butter repeater". Otherwise even >something as simple as an orignal Hamtronics COR-2 and an ID O'matic >cw unit would work very well. Understood. As I mentioned in a previous post, I did that this year for Dayton using an MP100. It was still small enough to pack the MVP & controller in one suitcase. Originally I just didn't want to be bothered with building another simple COS/audio/hang time/IDer for it, but as it turned out it was nice having a controllable 2nd port that I could plug the G707 into for linking back to Miamisburg. This application is a bit different. Although space is of no concern as it's a standard standalone fixed 2 meter repeater, the equipment paradigm that was adopted for this system was to have the controller installed inside the mobile case (the backup system is a Mastr II mobile with the NHRC Mastr II controller; I wouldn't have used it for the same reason I don't like the NHRC-MVP controller - displacing the superior GE CG board - but I didn't build that system). I am making progress with the NHRC-micro. Found one bad chip capacitor; replaced it & now it's decoding DTMF again. Now the audio output is getting noisy, & I see why: the audio output coupling cap is a 1 µF polarized chip cap, which feeds the MIC HI input of the MVP, which of course is biased @ 12 V for their mics. Care to guess which side of the chip cap the plus side is facing? I know high-capacitance non-polarized caps are hard to come by in SMC form, but controller manufacturers have got to face reality in that many radios bias the mic input. BTW, there is a solution to this problem that uses only polarized caps, but I've got to run down. Will follow up if anyone's interested. Bob NO6B
