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For the Uniden Washington/Cobra 142GTL:

Remove R104 (AMC limiter resistor), and replace with a 20k ohm trimmer pot, you'll have to solder this on the solder side of the PCB.
Remove R204 (560 ohm), and replace with a 1.5k ohm resistor.
Install a 1uf, non-polarized capacitor between pin 9 of IC4 (TA7222AP audio IC) and the junction of R204/D62/R121. The capacitor can be electrolytic, mylar, metal film, polyester, mica dipped or ceramic.
Remove the 2SC1419 at TR34, and replace with a 2SC1061, or NTE-152.

Set your deadkey to 2W at VR6.

Using a 1khz tone, and a scope, set your modulation on AM with the 20k trimmer pot you soldered in at R104. Adjust this trimmer until your NEGATIVE peaks are approximately 90%.

At this point you should have 180~200% positive peaks with no flat topping.

Wattage should be 2W deadkey, with PEP output at about 13-14W.

Good luck!

~Cheers~

<blockquote data-quote="ExitThirteen" data-source="post: 499067" data-attributes="member: 6878">For the Uniden Washington/Cobra 142GTL:Remove R104 (AMC limiter resistor), and replace with a 20k ohm trimmer pot, you&#039;ll have to solder this on the solder side of the PCB.Remove R204 (560 ohm), and replace with a 1.5k ohm resistor.Install a 1uf, non-polarized capacitor between pin 9 of IC4 (TA7222AP audio IC) and the junction of R204/D62/R121. The capacitor can be electrolytic, mylar, metal film, polyester, mica dipped or ceramic.Remove the 2SC1419 at TR34, and replace with a 2SC1061, or NTE-152.Set your deadkey to 2W at VR6.Using a 1khz tone, and a scope, set your modulation on AM with the 20k trimmer pot you soldered in at R104. Adjust this trimmer until your NEGATIVE peaks are approximately 90%.At this point you should have 180~200% positive peaks with no flat topping.Wattage should be 2W deadkey, with PEP output at about 13-14W.Good luck!~Cheers~</blockquote>

[QUOTE="ExitThirteen, post: 499067, member: 6878"] For the Uniden Washington/Cobra 142GTL: Remove R104 (AMC limiter resistor), and replace with a 20k ohm trimmer pot, you'll have to solder this on the solder side of the PCB. Remove R204 (560 ohm), and replace with a 1.5k ohm resistor. Install a 1uf, non-polarized capacitor between pin 9 of IC4 (TA7222AP audio IC) and the junction of R204/D62/R121. The capacitor can be electrolytic, mylar, metal film, polyester, mica dipped or ceramic. Remove the 2SC1419 at TR34, and replace with a 2SC1061, or NTE-152. Set your deadkey to 2W at VR6. Using a 1khz tone, and a scope, set your modulation on AM with the 20k trimmer pot you soldered in at R104. Adjust this trimmer until your NEGATIVE peaks are approximately 90%. At this point you should have 180~200% positive peaks with no flat topping. Wattage should be 2W deadkey, with PEP output at about 13-14W. Good luck! ~Cheers~ [/QUOTE]

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