Copper Talk » Open Forum » Archived Messages » 2002 » Archived Messages 02/01/2002 to 04/31/2002 » Pots for cobra 148 nw st « Previous Next »

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Joe
Posted on Saturday, February 16, 2002 - 3:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey. I need to turn my cobra 148 nw st down to 2 watts so i can run an amp with it. Also would like to turn modulation up to be loud but still CLEAN!!!!! Can anyone tell me wat the pots are that i need to turn? Also I have a watt meter for the power turn down, but how do i know if i am ajusting the modulation to the corect level? How is this done? Any help would be great!!!!!! Thanks
Joe
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GeneHackman
Posted on Thursday, April 10, 2003 - 12:31 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

1. DONT Remove TR24!

There are two methods to improve the AMC, you can change R130 (a 1.5KOhm for a 500 Ohm, it may be in a diode location close to TR26)

Or you can add a 1K resistor in series on the the middle leg of TR24, to do this just cut the track for the leg and put the resistor across the cut.
2. Change R126 (10k) to a 4.7K
3. Change R124 (10k) to a 4.7K
4. Re-tune L37 and L38 for maximum AM forward power.