Newbie with Cobra 29 LTD Classic

The other day I got a Cobra 29 LTD Classic that needed some repair.. The radio would receive some what but would shutdown on keying up.. Also the led was going bad and the meter bulb was out .. I am trying to order parts for the repair but I can't decide on green or blue display ?? But my main problem is I do quarry work and would like the most out of the radio (Distance)without using an amp because the CB radio might moved to different trucks.. Oh the trucks are using a Wilson 2000 antenna and quality coax cable too.. I am not looking for the crazy noises or such just clear and powerful radio.. Have any suggestions ??
Oh hold do I know if I have a older or newer model ???

Thanks


I found this withe some leg work

Cobra 29 LTD:

Receive Boost: Locate pin 14 of the PLL chip, and the Positive (+) side of C-12. Install a 22k-220k ohm resistor between these two points. The smaller the value, the more the receive is boosted. Use CARE when soldering to the PLL chip! If desired, this mod may be wired through a switch.

Supertune: Replace the stock final with a 2SC1969 unit. Solder a jumper across D8 (this may cause receive distortion at high volumes, remove jumper if it does). Solder a 68pf cap across C62. Solder a 68pf cap across C59 if there is already a 33pf across it. If there isn't, use 100pf instead. Replace R 55 with a 10-15k resistor, and solder a 33-55 pf cap across that resistor. Replace R58 with a 4.7 ohm resistor. Set VR4 just a bit to the right of half-way open. If D11 or C3 have been removed, replace them. D11 is a simple small-signal swithcing diode like a 1n147, and C3 is just a 1uf electrolytic. If TR18 has been removed or cut, replace with a 2SA733. Spread Open L12 a tiny bit, and adjust L16 for best swing, using a loud, steady "aaaaaaah" sound into the mic (or if you have a function generator, set it up for 1khz at about 16mv output, and use that. MAKE SURE to use heat-sink compound (a very light coating is sufficient) when mounting the new final, and MAKE SURE the final mount screw is tight!

MOSFET Supertune (29LTD classic and newer): Replace stock final with IRF520 MOSFET transistor (pin-for-pin match when installing). Remove R56 and in its place install a 470-ohm resistor in series with a common switching diode (1n914 or similar), with the banded end of the diode towards the front of the radio. Remove C53 and solder it across C59. In C53's place solder a 3.3k resistor. Remove C 61 and solder it across C62. Remove R55 amd solder a 22pf cap in its place. Remove the slug from L14. Replace C71 with a 33-47uf cap. Turn VR4 (AMC) counterclockwise fully. Gently spread L13 and L12 and tweak the spreads for best PEP when modulated. Tweak L20 and L17 for best PEP when modulated. After tuning is finished, set VR4 to half-way.

Note: Older 29's (LTD and GTL) use the same basic procedure, but instead of re-using the caps, place a 100pf across C62, a 68pf across C59, and 22pf across the spot where you removed R55.

Channel 9 switch to Channel 19: Cut D32. Hard, huh?

Radio comes in TX mode without mic plugged in: Check C117 and C118

Channel display goes dead on key-up, little or no receive: Check TR23 for bad part or bad solder joints. Also check C119.

 

What would you suggest??

 

I drive a Mac CL dump truck.. Sorry it ain't no big rig but it pays the bills for my family..

 

We run 1 whip on the driver side mirror and would like the dual antennas but they are not my trucks and not always in the same truck.. So hence why I am trying to mod radio .. I have looking around about the mods and there is alot of bad reports on the mods except for putting a 4700uf input filter cap.. But I will continue to search for better answers ..