The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

i got a cobra 19 ultra III mounted on my atv with a 4ft. firestik antenna.... its works purty good, but im the kinda person that likes to make things better.... so ive been searching for mods and stuff and i found this on another site... to me this info aint reel clear...




Not much can be done to these radios.
Replacing the final RF transistor with a 2SC1969 is a plus.
You'll have to solder a jumper across the diode going from the
Audio transformer to the Driver and Final.
Solder a jumper across the resister going from the base of the Final to the Driver.
The output loop coils towards the back part of the radio (usually by the Final) can
be spread apart, or pinched together to get maximum forward power.
You should see only about 5-7 watt increase. Don't clip the modulation diode.
Adjust the modulation VR pot.



now if anyone has any pics or any other info that would be helpful, please post
input will be greatly apreciated......

i pulled this pic of another thread on here cause its the same as the radio im wanting to mod.... could someone point out the "driver" and the "final"....if some one would point those out that would be a big help....

Im not an expert but Ill try to help the final is in the left rear corner of radio. It will be bolted to the frame of the radio. It should say c2078 on it or just 2078 on it . The driver looks like the final but im not sure what number will be on it but will be fairly close to final . Just make sure if you change the final to put the insulator off the old one on the new one so it doesnt ground out to the radio case. You might just try turning the modulation pot first it will usually make quite a bit of difference on these.

aight thanks... i try it

Never ever jumper the diode connected to the transformer! Butcher shops do that! The diode is there to protect the modulation transformer.

timrim wrote:Never ever jumper the diode connected to the transformer! Butcher shops do that! The diode is there to protect the modulation transformer.

does that mean theses instructions are bullsh*t ?

I dont know if the 1969 will work in the cobra dx , If you turn up the modulation pot and make sure you have good swr's , your do about all that radio is capable of. Not sure if an atv has enough ground plane for you to get you swr low enough. Possibly cophasing two antenna's will work better as they will use each other to make your grond plane . Do you have and swr/ watt meter ? Setting it up right will work better than pumping up the radio and then reflecting it all back to the radio.

yea i got a meter ......


thanks for all the input