And another thing, the 6 cavitie small mobile VHF duplexers are rated around 70dB isolation at 5MHz. How are you gonna keep that spec and narrow the BW by over 10X?
prcguy
That would fall under my previous post where I stated that I wasn't advocating the use of a 5 MHz spaced mobile duplexer. Remember that? It was only yesterday. I'm just saying that for a low power portable repeater, one doesn't need a $2000 high performance duplexer. One can get by with less.
I hear what you're saying, I understand, and I agree. But isolation requirements aren't always that stiff, if some intelligent compromises are made.