.: ICOM IC 271 frontend mod.

I just have bougt a used IC 271 and the it seamed deaf . I made some msurement on the sensetevity it were 0,23uV for 10DB S/N. I replased the Q7 3SK48 on the RF.YGR bord with a BF988 and replased R18 100ohm with a 47ohm after that the sensetevity where 0,11uV on  144.3MHz and 0,06uV on 145.9MHz. And after justing helexfilters 0.05uV on 144.300MHz.

i have made the same replasedment of O7 on a a IC271H. Before 0,09uV for 10DB S/N after 0,05uV for 10DB S/N

.: ICOM IC 271 bad modolation on SSB

My IC271 alsoe hade a bad modolation on SSB , but not on FM. after a invistagition i fond out that the BFO frequency on the main board where wrong and the sideband hit the SSB filter at rong frequency resulting cutting the low freqency of the modolation. After adjysting the BFO USB to 10.7485MHz  modalation wehere perfekt.


   standart filter



frontend bord

BF988 on botton side


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