General Lee Radio Problems No Modulation On Low Power & Other Problems

unfortunately CB Tricks site is down again, so it's going to be tough to answer your questions without a schematic. The diode that you are talking about, are you saying that it was on the solder side of the board going to one leg of the power transistor? I assume you are talking about the diode on the component side of the pcb, which goes to one lead of the audio transformer. If its on the component side, I'm sure you probably know that there should be a little silk screen image of the diode that shows which way it should go. If the diode was on the solder side, then it may have been put there as a Mod of some sort? Is D91 still there on the component side?

Is this radio using IRF520's? If you haven't already, check the voltage regulator, I think its B827. Make sure it's output is okay, and not over driving the IRF520 transistor. The regulators middle leg should be between
3 - 7 volts I think. If all 3 legs are around 13 - 14 volts, then the regulator is shorted. I hope this helps.

 

These voltages are probably correct, the bad thing is that the radio is getting hot so there is a component somewhere that maybe shorted. It would sure be nice to know what that diode's job is and where its suppose to be in the circuit. Without a schematic, it's like looking for a needle in a haystack. Is there 3 IRF520's in the radio? One should be the TX power transistor, and the other two I believe are the drivers. You may try de-soldering each transistors one at a time, and see if the 2SB754 still gets hot.

 

Yeah what the hell is going on with this?

it is like mp3car.com, great site, could have been a paid subscription site but the owner took it down.

 

Okay, thanks for the pictures. I'm sorry, but I said it backwards about the 520's. looking on the component side, the far left 520 (the one that's kind of by itself) this transistor is the driver. The middle transistor and the one to the right (closest to the middle of the radio) are the TX finals. I didn't think to ask if you had checked the bias on them. The gate voltage on the driver should be around 3.75 volts, and 3.55 volts on the two finals. Also, if you haven't already, it might be worth checking the ceramic insulators to make sure they aren't cracked. I wish I could be more help, but I'm not that familiar with this radio. I think the Connex 3300HP is the same board. If you could only get your hands on one, it might help you figure this out.

 

Yes, it's very unfortunate to have such a valuable website not be available from time to time. I've noticed on other forums some of the guys said they would be willing to donate to help keep CB Tricks going. But I guess the webmaster must not of been interested in the offer? What ever the reason, its a shame to loose it.

 

I looked for the email for the owner, i thought I had it but ...

I would consider taking it over and mp3car.com ...