I've used a TX/RX mobile duplexer with very good results. Mine was tuned up at TX/RX, although it was originally in the commercial band. The TX/RX units are better (in my opinion) than the typical "flat packs" made by others. Although I have used the flat packs in the ham band with good luck. Again, I'm talking about UHF.
Chuck WB2EDV ----- Original Message ----- From: "Eric Lemmon" <[email protected]> To: <[email protected]> Sent: Sunday, June 21, 2009 5:43 PM Subject: RE: [Repeater-Builder] Mobile Duplexer for 30W repeater ok? > Tony, > > Most UHF mobile notch-only flatpack duplexers will work fine below 50 > watts > at a 5 MHz split- but their performance rapidly deteriorates when operated > outside of their stated band limits. For example, a commercial-band > mobile > duplexer that was manufactured to operate in the 450-470 MHz band will > likely perform poorly in the 440-450 MHz Amateur band. Although such a > duplexer may SEEM to be working in the Ham 70 cm band, it may have > excessive > insertion loss that the owner may not realize. That's because the > coupling > loops are set at the factory and not readily adjustable by the owner. > > I once tried to use a commercial-band mobile duplexer on 70 cm in a > portable > repeater, and was disappointed in its performance- especially receive > sensitivity. I then ordered a new Celwave duplexer of the same model, but > factory-tuned for my Amateur pair. What a difference! Once the new > duplexer was installed, the range of the portable repeater was > significantly > improved, with no other changes. > > 73, Eric Lemmon WB6FLY > > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of [email protected] > Sent: Sunday, June 21, 2009 1:47 PM > To: [email protected] > Subject: [Repeater-Builder] Mobile Duplexer for 30W repeater ok? > > > > Just a double-check question. I'm thinking of buying a UHF mobile duplexer > to use with my repeater at home. Since I'll only be running 30 watts, any > opinions if this is a bad idea? > > Most of the older style "cans" are getting higher auction prices, but some > mobile packs are pretty reasonable. > > Thanks, > Tony KT9AC > >
