Maybe check R84 and particularly R85 are the correct values, and doesn't have any dry joints? I'm guessing that Q12 takes R84 in/out of circuit in order to set bias current on Q22, and if Q12 is open circuit to set optimised bias current, and there is a problem with R85, the post mixer amplifier won't work properly?
73, Matt VK2RQ > On 25 Feb 2015, at 12:35 am, Don Palmer <[email protected]> wrote: > > Hi hope someone can help me I have just finishing building a K2 when I > change OPT to Optimization I lose sound. > > I put it back to BATT and it all comes back, I understand that this command > reduces the I.F. > > post-mixer amplifier current by about 40 mA and automatically > > forces the bargraph to use DOT mode if set for BAR. > > > > Any help would be grateful. > > > > Don > > G6CMV > > K2 Ser Num 6546 > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
