I ran across this on another forum and found it to work realy good for the Cobra 29.It may be of use to some.
Add a 1/4 watt 4.7 ohm resistor from the + side of C116 to the gate of the 2030 this is the left leg looking at the face of it. Replace C62 with a 390 PF Cap. The post suggest to jump D8 but I left mine alone. Went from 2 watt dead key to 8 watt.This will also incress the swing.
Now my question is does anyone know if this can be done to the Cobra 25 and how ?
Mod for Higher Dead Key With Cobra After ERF 2030 mod
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- speedracer6g
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Sure can!!
-instead of using a 4.7k use a 10k pot or 100k. set your gate voltage to about 2.7 to 3volts. Do this by putting a voltmeter on left most leg of the mosfet final when looking at the face of the transistor.
-remove C45
-remove C46 and install a 480pf capacitor.
Also do not put a jumper on D8 because that is bad I have seen radios go up in smoke that diode is there to prevent feedback into the audio ciruit.
happy modding
Mike
-instead of using a 4.7k use a 10k pot or 100k. set your gate voltage to about 2.7 to 3volts. Do this by putting a voltmeter on left most leg of the mosfet final when looking at the face of the transistor.
-remove C45
-remove C46 and install a 480pf capacitor.
Also do not put a jumper on D8 because that is bad I have seen radios go up in smoke that diode is there to prevent feedback into the audio ciruit.
happy modding
Mike

Call me blind, but I don't see a C116 in the Cobra 25. Can someone tell me where it is located?speedracer6g wrote:Sure can!!
-instead of using a 4.7k use a 10k pot or 100k. set your gate voltage to about 2.7 to 3volts. Do this by putting a voltmeter on left most leg of the mosfet final when looking at the face of the transistor.
-remove C45
-remove C46 and install a 480pf capacitor.
- speedracer6g
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- First Name: Michael
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Re: Mod for Higher Dead Key With Cobra After ERF 2030 mod
Sorry I might have that wrong I will check that agian and get back to you.
MIKE
MIKE
- speedracer6g
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Re: Mod for Higher Dead Key With Cobra After ERF 2030 mod
On a Cobra 25 it goes on the center leg of tr16. Sorry about that.
MIKE
MIKE