At 03:38 AM 3/2/2007, you wrote: >Picked up a vertex VXR 7000, and a Celwave 6 cavity duplexer. (VHF)
<---What type? One of those mobile notch-only type? How about a model number? >Using Celwave pd-220 3a, with 25 feet lmr. <---Some folks recommend against using LMR in a full duplex system (this topic has been beaten to death on this list by the way but there are good articles at the RB website explaining why) >We have spent hours tuning the duplexer, and find that it makes the >system deaf. <----Keep reading... Using an HT to generate and notch the signals, (as well as a power meter and a swr meter) all looks good until hooked up and its deaf. A user a half mile away can barely hold the repeater on an ht at 5 watts. <----An absolutely HORRIBLE way to tune a duplexer. But still I'll ask - what type of duplexer and,if a notch-only mobile type (which those small ones are), did you tune for notch or pass? And I bet you didn't use 50 ohm pads when you tuned? >Using an HT to generate and notch the signals, (as well as a power >meter and a swr meter) all looks good until hooked up and its deaf. A >user a half mile away can barely hold the repeater on an ht at 5 >watts. > >I fully understand that there is attenuation inherent in duplexers, >but this is way too much. freq pair is 4 mhz split, antenna system >and cabling is excellent, rx and tx on the repeater is great, >duplexer is in excellent shape. > >Anyone have any ideas? Are our crude methods of tuning the duplexer >too crude? we tune the high to pass the high and notch the low (and >vice versa on low side) but the duplexer seems to attenuate much >more than expected. <---See above
