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Madison TX problem

Oct 15, 2008
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Hello all! I have a Uniden Madison with the PC-411A board. Had to put it into storage a few years back and it was working fine. When I got her out, it had no transmit. After reading up on this site, I replaced all the electrolytic capacitors in the radio with new ones (using the recomended voltage upgrades). Replaced the voltage regulator, driver and final with new parts. Problem is that it only puts out 1 watt TX. Recieve is fine (actually it's great after the capacitor replacement). She is modded for extra channels, variable wattage and FM. I was wondering if anyone else has had this problem. I have no test equipment, only a VOM. The radio has great sentamental value to me and I'd love to put it back where it belongs; on the air, so any help would be greatly appreciated.
 

Welcome to the best forum and group of guys anywhere. Two questions will be asked. Is it the older Madison with the 858 PLL or the newer design with the 8719 PLL ? If it is the newer design it shares similarities with the Cobra 2000 and on this forum there are a few real professionals who know that chassis inside and out.


3's
 
It has the 8719. Sorry, I should have put that info in the first post. It's one of the last series of Madison with the digital clock.
 
if you dont have a wattmeter; how do you know the radio is only putting out 1 watt?
could just be that the internal meters need re-adjusting.

after major surgery like a re-cap, your radio ABSOLUTELY needs a complete alignment.
PLL- RX-TX-metering etc...

your best bet is to send the radio to a good shop to have them give it an alignment, (not just a "peak and tune") and they will be able to tell you if there really is a problem with it.

it would be a good idea to thoroughly check all the new caps to make sure you put them in correctly with regard to the polarity before you send the radio to a shop.
if the tech at the shop has to search around for a backwards cap, its going to cost you some money.

when you say that you replaced the driver, final and regulator; what parts did you replace them with?
were these parts from a used radio?
where did you get the 2SC1969 final from? (there are lots of fakes out there)

my personal recommendations for a shop would be DTB radio or Sparky's CB shack.

many of the "truck stop" CB shops dont know how to give a radio a complete alignment even if they did have the required test equipment.
you definitely need a reputable shop.

if you run into problems, PM me here on the forum and i will try to help you out.

you have a great radio there and it deserves to be healthy! LOL
LC
 
Thanks for the replies! I think your right. I need to buck up and send her to a GOOD shop. I've spent enough money buying parts over the last year that I could have had her fixed! Again, many thanks. You guys deserve it!
 
I ve had looked at radios here that had low or intermitent output and pushing around on the board showed bad solder and reheating the 3 legs on the final stage transistots brought everything back to life Ive seen this in Cobra 148 radios.
 

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