Fault finding need help..transmitt carier on am normal 4 watts no modulation on am and no modulation on ssb usb/lsb.receive is alright.checked mic insert -inside mic etc and other end mic plug all ok their.
It looks like you had some loose connections in that CB. you may want to also check for other cold solder joints throughout the units and touch them up with some solder. Might I suggest you use a desoldering tool and then just add new solder to the connection.
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fuyt back .found predriver 2sc1906 was blown replaced with 2sc1966.final ok.noticed now that the final and driver had 13 volts readings on the base .when switching mode switch am should read 5.50 volts when switch mode switch usb/lsb should read 13.75 volts.checking tr41 dc reg transister also tr42dc reg transister end of press i will be back ......
fuyt back tonight 11.20pm been in the garage working on the cb radio put back ic6 found that i could hear my modulation my voice on all modes lsb/usb/am connected another cb radio besides the president radio .mod was low not even moving the needle but i could hear myself looked inside cb again from the mic gain control 2 wires going into the amp stage tr 29 was a bc 458 this did not look right and while touching the legs with my fingers my modulation increased and the watt meter started too peek up.took out tr29 and replaced with a bc945 and wow modulation now on all mode lsb/usb/am.same probem with another cb cobra 148 my friend wanted fixed.my other email is [email protected] cobra cb radios .
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