For what it's worth, the FCC authorized repeater sub-bands for 2m are 144.5-145.5 and 146.0-148.0, so putting a "repeater" input (or output) square on 145.5 will likely have part of the "repeater" operating outside the sub-band if that matters to you.
Mike/W5JR ---[Original Message]--- From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Oct 3, 2008 3:07:08 AM Subject: [Repeater-Builder] Re: Portable Temporary Repeater <<"Observations, suggestions, and your crazy are appreciated!">> Unfortunately I have to add myself to the list of naysayers but to answer as you requested: "Basically the question is: at a 2 mhz seperation (odd split) on VHF can one get away without using duplexers (cans), utilizing separate rx/tx antenna's, spaced about 20 ft apart! Without desense or other issues" NO. Inadequate physical separation, inadequate frequency separation, especially using the equipment described. "Being such a remote area, and the nearest 2 meter repeater is well over 50 miles away, and nowhere near these frequencies - 145.500 rx/147.500 out using a tone of 179.9, I do not see any interference issues there!" As you suggest, the likelihood of interference is small but NOT nonexistent. If it were me, I think I'd have a receiver (on carrier squelch) monitoring your repeater output just for the purpose of CYA. Overkill? Maybe, but as the movie actor asked, "Do you feel lucky today?" At least you could answer truthfully that the frequency was monitored. --- In Repeater-Builder@yahoogroups.com, "Louis" <[EMAIL PROTECTED]> wrote: > > I apologize if this has been addressed previously, or even close! Do > not have a substantial amount of time to complete this research! > > Situation: An event in a remote area, one hill top is well enough > that coverage at around 10 watts VHF for the repeater could cover most > of our Aid Stations, 2 with HT's, the other 3 with Portables at 25 > watts or so, could get into the repeater! > > In the past, we have used crossband UHF in, VHF out, and it worked ok! > Except for issues with a couple of HT's not being able to cut the > input out during transmit! My goal, is to design a lite weight, low > power consumption (i.e. fewest batteries possible, as the hill top is > only assessable by hiking or horseback! > > What I have on hand: > > Single band 2m HT for receive > Single band Yaesu 2M FT2800R for transmit @ 12.5 watts! > Pair of homebrewed 2 m aluminum j-poles > > Need to acquire: > > simple controller - NHRC-2 looks workable! > batteries - based on estimated power consumption of final configuration! > > > Basically the question is: at a 2 mhz seperation (odd split) on VHF > can one get away without using duplexers (cans), utilizing separate > rx/tx antenna's, spaced about 20 ft apart! Without desense or other > issues! > > Being such a remote area, and the nearest 2 meter repeater is well > over 50 miles away, and nowhere near these frequencies - 145.500 > rx/147.500 out using a tone of 179.9, I do not see any interference > issues there! > > Observations, suggestions, and your crazy are appreciated! > > Thank You, > > K1STX >
