One of my project radios is a Motorola APCOR box. Basically a 463 mhz EMS portable repeater, like the orange box you see int he old TV show Emergency. The only issue is that the duplexer is connected with real small rigid coax and it is upside down frequency-wise. It receives 463, transmits 468. But the duplexer isn't symmetrical, it's like 4 notch cavities one side and three teh other. In a duplexer you (most of the time) need to keep the frequency sense the same, one port always the lower, one the higher, regardless what's hooked to it. But the point is that these are self contained and have nicads in them. If you can find an APCOR unit it can be a pretty good portable repeater. They came in 1 watt and 12 watt versions. Oh yeah, the radios are a pair of MX300's. And those are plentiful on ebay, for making portable repeaters. George Csahanin W2DB WQEU782 Cedar Park, TX