Lot, The specification sheet for this duplexer shows 70 db of isolation. That may not quite be enough.
I have a Q2330E which Sinclair claims 85 db of isolation. I was able to carefully tune the duplexer to obtain 91 db of isolation at 147.280/147.880. With a 75 Watt Micor repeater station and factory Motorola preamp I have no measurable desense. When I tried a ARR preamp I had 2.5 - 3 db of densense, so went to the factory Micor preamp which has a little less gain. I much prefer to sacrifice a little sensitivity to eliminate densense. I am not all that familiar with what your VXR repeater needs for isolation but I think 70 db is going to be a problem even if you run pretty low power. You could also add some additional cavities between the transmitter and receiver ports to the duplexer to increase your overall isolation. Good Luck, Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, "Lot" <k6...@...> wrote: > > Hi Everyone, > We are setting up a project in Manila and would like to ask some help with > information about a good repeater duplexer. > I saw one in Ebay, (Sinclair Q2220E VHF BpBr Repeater Duplexer). > Is this a good type of duplexer and would work on a typical repeater setup? > We will use it on a VXR7000. The Repeater Frequency will be at 144.880 - > 0.600. > Any information will be very much appreciated. > > Thanks! > Lot / k6irf >
