At 12/12/2007 06:06, you wrote: >One for the wonderfull experts here. I have been working to many >nights this week to be able to think straight. > >Our MastrII converted mobil developed a spur problem last nite. Were >on 145.43 and the spur was on 145.11. Very strong and subbing in a >standy unit produced the same results. The only components used in >both are the ICOMs and the stock tone card (used to encode tone >only). The fix was to pull the reciever ICOM (144.83)killing the >local rx. Guys what are your thoughts on this and the possible fix.
I've had this happen with both the VHF & UHF Mastr II mobiles (though not "strong", more like anywhere from -50 to -80 dBc), which is why I now consider that particular GE mobile unit unsuitable for repeater use unless the RX or exciter is removed & separately packaged. AFAIK the Exec II & MVPs don't have this problem, possibly because the TX exciter & RX LO chain aren't sitting side-by-side. I've tried bypassing the 10 V supply & adding shielding to the exciter area to try to prevent coupling between the RX LO chain & exciter, but have had no success. Bob NO6B
