The commercial diplexer might only have to deal with two transmit or receive frequencies feeding one antenna. As such wouldn't the bandwidth on each port be relatively narrow?
For use with two repeaters, the VHF port would need to pass both the TX and RX freqs at 600 kHz or 1 MHz separation, and the UHF port would need to pass two freqs 5 MHz apart. I would think that this kind of bandwidth on each port would be rather difficult for a diplexer, as now you're actually talking about four freqs through the feedline/antenna. Perhaps this is why TXRX said they couldn't or wouldn't provide something. Or am I all wrong about the bandwidth issue? I'm looking at it from a duplexer point-of-view. Bob M. ====== --- Doug Bade <[EMAIL PROTECTED]> wrote: > Kevin; > > Their perspective is the commercial world > and dual band > single antenna repeater systems do not really exist > in these bands > using that narrow view..... split in at the bottom > and split out at > the top they do, but not a dual band antenna. You > are quite correct > that it is not an issue if the antenna is a dual > band, but not in > their version of the world... Never ask the factory > those kind of > questions.. :-) They are not very amateur centric in > this realm. > > I think as I mentioned, they mis-understood > what he needed.. > > They also do not know that a T-pass > combiner can be used > cross band (VHF/UHF) also, but that is another > discussion .... :-) > > TX/RX has great stuff but sometimes it is > tough to get > someone who thinks outside the box on the support > staff.....although > there are several folks there who are quite > knowledgeable and > normally very helpful. > > Doug > KD8B > > > At 09:55 AM 11/14/2005, you wrote: > >n2len wrote: > > > > >Thanks for the info, I called them this morning > they explained to me > > >they can build a combiner using the same feedline > feeding different > > >antennas but not a combiner using the same > antenna for 2 different > > >uhf & vhf repeaters... > > > > > > >I don't know why they would have told you that, > unless they didn't know > >that companies make multi-band antennas... > > > >The diplexer doesn't know (or care) how it is being > used, and in this > >scenario, only one diplexer is needed; at the > bottom. > > > >Kevin __________________________________ Yahoo! FareChase: Search multiple travel sites in one click. http://farechase.yahoo.com 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/