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need help again with mic wireing , t command

i have anouther question ,, after looking at the websight

http://www.hardtimez99.com/SECRETCB29/bookz/SECRET_CB_VOLUME_3.pdf


i see where it says

tea berry (t ) command
adjust L15 and L12 for maximum RF power
adjust VR5 for 100% modulation or cut D14
VR6 : modulation meter adjustment
VR4 : RF meter adjustment
connect pin 19 or IC3 to 4.84v source for new frequencies ( channels 1-26 )



ok i looked in my radio and saw that the ( D14 ) had already been disconected ( not cut but one side un-soldiered ) , i dont plan on adjusting any of the things they say to adjust , because as yall know i dont know much about this all ..

but i do feel that i can maybe do the last step ( connect pin19 to a 4.83v source ) ,, but what im wondering is , what does it mean by new frequencies on channeks 1- 26 ?? and how will this help

Ok you need to be very careful when soldering around the PLL chip it can easily be damaged by static-electricity or by overheating if you hold the soldering iron on the pin for too long! Also, they don't mention the use of a pull up resistor, which would be recommended to restrict any large current flow (unless there is one built into the PLL chip). For what you will gain for the mod is it really worth risking the rig.

See if you can find a copy of the "screwdriver experts guide to cb radio"
not sure of the author and the "CB Eprom Data Book by Martin Pickering", they will help you understand the inner workings of the radio and how the voltages on each pin of the PLL chip control its frequency.
Do some reading, and buy some cheap old 40 channel cb's and play around
with them, rather than risking your only working set.

Congratulations on wiring the mic, it feels good when you do something for the first time and it works, well done!
Cheers Mark (y)
26ML205
 
Okay. The radio's mike socket uses pin 1 for audio, pin 2 for transmit and pins 3 plus 4 both as ground.

Audio for the factory cord is white, with shield wrapped around it. Goes to pin 1

Transmit wire is red, goes to pin 2. Just beware hundreds of Volts DC on that pin while receiving.

Blue gets combined with the shield. Should probably bridge pins 3 and 4 together inside the mike plug. This pair of wires goes to pins 3 and 4.

73
 
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