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the voltages going to the collectors of the driver and final look a bit low.

in AM mode with a 4 watt carrier, you should measure around 7 volts on them.

this voltage is provided by TR41 and TR42 and is the place to start looking for problems.
in AM TX you should measure this on TR41:
E-5.8v
C-13-13.8 volts
b-6.8 volts or so.

if its a new 148GTL (front mic) make sure VR501 is turned up.

if its an old 148GTL (side mic) check TR42 and if bad replace it with a 2SC945.
also look for old dried out electrolytic caps around the audio amp and TR41.
LC

[QUOTE="loosecannon, post: 264923, member: 1368"] the voltages going to the collectors of the driver and final look a bit low. in AM mode with a 4 watt carrier, you should measure around 7 volts on them. this voltage is provided by TR41 and TR42 and is the place to start looking for problems. in AM TX you should measure this on TR41: E-5.8v C-13-13.8 volts b-6.8 volts or so. if its a new 148GTL (front mic) make sure VR501 is turned up. if its an old 148GTL (side mic) check TR42 and if bad replace it with a 2SC945. also look for old dried out electrolytic caps around the audio amp and TR41. LC [/QUOTE]

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