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Manenti
New member
Username: Manenti

Post Number: 2
Registered: 9-2006
Posted on Wednesday, July 18, 2007 - 8:33 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

How do you adjust carrier power on the PC 78 Elite?
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2590
Registered: 9-2004


Posted on Wednesday, July 18, 2007 - 6:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

remove JP36. its near the final.
solder a 220uF 25 volt electrolytic capacitor in its now empty holes. the negative lead of the cap goes toward the final. (back of radio)
now solder a 1/2 watt resistor to the leads of the cap. do this on the solder (green) side of the PC board, keeping the leads of the resistor very short, and using heat shrink tubing on it to prevent shorts.
just solder each lead of the resistor to one of the places where you soldered the cap to.
this would be considered "in parallel". just FYI

experiment with the value of the resistor to vary the deadkey. swing will always be the max the radio can do no matter what the deadkey is.
try a 10,22, or 33 ohm resistor to start with and see where that puts you.

i wouldnt go much below 2 watts, as it makes the radio sound funny. thats just my opinion.

put D11 back in the radio if you have removed it, and turn VR4 all the way up.
tune L14 for max PEP wattage, while saying "ahhh" into the mic.

should be just right to drive a 2 pill amp, and be very loud!
have fun,
matt
anyone wanting a "clean signal", just look to the left and build one of these!!!

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