Connex 3300hp help

I had this same issue after several yrs of having my General Lee HP, basically same radio as yours just different face plate.
Was told its what's called by my CB Dr 'Cold Solder', basically it could be anywhere in that radio that can possibly never be found.
You said it works fine for about 10min just enough time for it to warm up & a loose solder joint somewhere gets weak.
Mostly occurs either if it has been dropped or just yrs of bouncing around in a truck, i know there strapped nice & tight but believe or not they still get abuse.
I was advised to send it down the road so that is exactly what i did.
Best of luck to you these are kick ### radio's & it sucks when they crap out, maybe try another Dr to see what he comes up with.

 

Get 'er warmed up and then use freeze spray in different areas of the board. You might get lucky

 

I would refloat the grounds on the board, or just refloat the board in general.

 

Techs have to be clueless.

Get some of this and go through section by section with it,

 

Its a tool for sure, but so is a heat gun, and a BFH. tap tap..

 

If it hasn't already been done, make sure all the PCB screws are tight. Loose screws can cause strange issues too.