Mike i have watched your videos for the past year, have learned a lot, currently trying to get my troubleshooting skills up. it is easy to swap parts but to have the skill of reading charts and diagrams is getting to be a lost art. keep up the good work.
Hi Mike, Great explanation as always, but you forgot C302. A 10uf electrolytic across the output of the voltage-regulator pc board. When it opens up from age and mileage the regulation goes to the doggies. We got in the habit of replacing C302 in every 2000GTL we touch. Cheap insurance against a callback weeks later, even if the part is good. If you don't believe me, pull C302 out of a radio and see how it regulates under full transmit load. Keep up the good work and 73 Chris
glad to see this finally up on youtube! as i said in my comment on your last cobra 2000 video, i have done this exact repair on quite a few 2000's. i drill the hole in the back corner of the switch, and just spray the contact cleaner in there. it has worked every time ive done it. great video.
@@FuturesBrizio on the back of the switch. either side of center where its flat. drill through the black plastic. set a depth stop on the bit so it can't grab and pull itself in to the switch. just tape around the bit exposing just enough so that the bit can get through the plastic, but no more. drill slowly and remove the cut plastic as you go so you don't get any inside the switch. then just spray in contact cleaner and shake the switch around. drain it out the hole and actuate the switch a bunch of times. repeat this process a few times, then re-install.
I have a 2000 gtl and low voltage as well. Whwn I switch to side band from AM the dim CB channel gies out completely. I read 13.6v from the piwer supply at the fuae and the switch seems to be fine. The brifye rectifier tested fine. Someone told nne it is likely the voltage regulator. This system was in storage.
Been a ham a long time, but never seen a setup like that. Great explanation Mike, thank you for another great video. I learn a great deal from your work!
I just picked up a cobra 2000.. I can talk on AM just fine But if I try to modulate on USB or LSB all the lights dim down so bad that you can barely see the meters.. Is this a power supply issue or something else.. Should I replace the power supply.. I am wondering why it only does this on Side band.. Thank You for any advise on this..
Not sure how many hack jobs I have seen on the 2000. Specially in the power supply. A lot of techs do not understand the switched grounds in these. Great explanation mike.
A friend of mine had a 2510 done caps and "re-tune" by Mr. Snake and when he got it back it sounded like crap on SSB i felt so bad for him after he payed a lot of money for him to swap caps i told him ill take a took at it and it took me the good part of the day to undo what he did and realign it. I am not a shop i just have a 100Mhz scope a 8 digit freq counter that i adapted a Tcxo in to it and a $60 freq gen. any how it was WAY off freq and the bias was all most at 0v among other stuff... they call you a snake because you snake people out of there money.. now i don't call my self a real Tech i went to school for electronics and CNC I got my general class license in 2014 so i am still new and just play with radios I just do stuff for friends. I got a fix or repair Kenwood TS-450Sat off E-Bay and i was so excited when i got that baby working. I all so did a few 148GTL's for friends... but dude you suck...
@SNAKE RADIO CUSTOMS BUILDS AND MODS ROFL dude i have seen your work you get a C- . You have been called out a few times and you need to take it as a learning experience. you f%^#ED up Snake OIL Customs.
lost power supply on a Uniden 40 Channel CB radio base station ? it works on the 12 volt plug . when you get time can you show 1 of these ? Thanks for your videos .
richard watson Not much to a simple linear AC/DC power supply. Check the step down transformer voltage, bridge rectifier and regulator transistors. Also check if there is a fuse on the power supply board. Many radios have more than one fuse. If it has a AC/DC switch be sure to check that to.
@@mikesradiorepair yeah I wished I had someone around here that could learn me how to work on them I am just been in it for since 1985 and just started working on them I have a Cobra 2000 that will not transmit will not receive but with a radio setting beside it it will a little any ideas
I guess if the voltage did not change when you fiddled with the power switch it could be at the other end where the switch provides the "ground" to the radio PCB (loose connection, bad solder joint, etc.). More likely the switch though since it is exercised mechanically way more often. Nice video Mike, thanks!
Thanks for the tutorial Mike. Can you tell me what the transformer secondary output voltage is on those radios, I'm having some uniden washingtons sent over to Aus from the US and will need to replace the transformers for 240 volts.
Mike i have watched your videos for the past year, have learned a lot, currently trying to get my troubleshooting skills up. it is easy to swap parts but to have the skill of reading charts and diagrams is getting to be a lost art. keep up the good work.
Hi Mike,
Great explanation as always, but you forgot C302. A 10uf electrolytic across the output of the voltage-regulator pc board. When it opens up from age and mileage the regulation goes to the doggies. We got in the habit of replacing C302 in every 2000GTL we touch. Cheap insurance against a callback weeks later, even if the part is good. If you don't believe me, pull C302 out of a radio and see how it regulates under full transmit load.
Keep up the good work and 73
Chris
That always gets replaced when I do one of these.
glad to see this finally up on youtube! as i said in my comment on your last cobra 2000 video, i have done this exact repair on quite a few 2000's.
i drill the hole in the back corner of the switch, and just spray the contact cleaner in there. it has worked every time ive done it.
great video.
Can you specify exactly where you drill that hole? I’d like to try that on mine. Thanks.
@@FuturesBrizio on the back of the switch. either side of center where its flat. drill through the black plastic. set a depth stop on the bit so it can't grab and pull itself in to the switch. just tape around the bit exposing just enough so that the bit can get through the plastic, but no more. drill slowly and remove the cut plastic as you go so you don't get any inside the switch.
then just spray in contact cleaner and shake the switch around. drain it out the hole and actuate the switch a bunch of times. repeat this process a few times, then re-install.
Do you work on a Cobra 2000 I need one repair
Good job. Thanks for sharing.
Great radio, but lots of problems.
Another good video.
Best regards
I have a 2000 gtl and low voltage as well. Whwn I switch to side band from AM the dim CB channel gies out completely. I read 13.6v from the piwer supply at the fuae and the switch seems to be fine. The brifye rectifier tested fine. Someone told nne it is likely the voltage regulator. This system was in storage.
Been a ham a long time, but never seen a setup like that. Great explanation Mike, thank you for another great video. I learn a great deal from your work!
where di Milke go? is there another place we can follow and continue to learn? is Mike ok? my respects sent !
I have seen exactly the same fault on the President/Uniden Washington, voltage drop through the switch.
I just picked up a cobra 2000.. I can talk on AM just fine But if I try to modulate on USB or LSB all the lights dim down so bad that you can barely see the meters.. Is this a power supply issue or something else.. Should I replace the power supply.. I am wondering why it only does this on Side band.. Thank You for any advise on this..
Not sure how many hack jobs I have seen on the 2000. Specially in the power supply. A lot of techs do not understand the switched grounds in these. Great explanation mike.
I guessed right when you showed the schematic but it was just a guess based on what you had said. I am learning!!! Yea!!!
snake radio can learn something here
I doubt it. Snake Radio is a "legend in his own mind". LOL
A friend of mine had a 2510 done caps and "re-tune" by Mr. Snake and when he got it back it sounded like crap on SSB i felt so bad for him after he payed a lot of money for him to swap caps i told him ill take a took at it and it took me the good part of the day to undo what he did and realign it. I am not a shop i just have a 100Mhz scope a 8 digit freq counter that i adapted a Tcxo in to it and a $60 freq gen. any how it was WAY off freq and the bias was all most at 0v among other stuff...
they call you a snake because you snake people out of there money..
now i don't call my self a real Tech i went to school for electronics and CNC I got my general class license in 2014 so i am still new and just play with radios I just do stuff for friends. I got a fix or repair Kenwood TS-450Sat off E-Bay and i was so excited when i got that baby working. I all so did a few 148GTL's for friends...
but dude you suck...
@SNAKE RADIO CUSTOMS BUILDS AND MODS
ROFL dude i have seen your work you get a C- . You have been called out a few times and you need to take it as a learning experience. you f%^#ED up
Snake OIL Customs.
@SNAKE RADIO CUSTOMS BUILDS AND MODS
you need to send make some money for all the Classes you are taking at MikesRadioRepair school..
@SNAKE RADIO CUSTOMS BUILDS AND MODS
ROFL your crazy dude you had videos on your page back in the day working on 2510's your a liar liar pants on fire
lost power supply on a Uniden 40 Channel CB radio base station ? it works on the 12 volt plug . when you get time can you show 1 of these ? Thanks for your videos .
richard watson
Not much to a simple linear AC/DC power supply. Check the step down transformer voltage, bridge rectifier and regulator transistors. Also check if there is a fuse on the power supply board. Many radios have more than one fuse. If it has a AC/DC switch be sure to check that to.
Mike this is Harvey Miller in Mississippi do you still work on Cobra 2000 radio
Yes I do. Don't work on a lot of CB's these days. It's mainly amateur and commercial radios but I toss a CB in every once in a while.
@@mikesradiorepair yeah I wished I had someone around here that could learn me how to work on them I am just been in it for since 1985 and just started working on them I have a Cobra 2000 that will not transmit will not receive but with a radio setting beside it it will a little any ideas
I guess if the voltage did not change when you fiddled with the power switch it could be at the other end where the switch provides the "ground" to the radio PCB (loose connection, bad solder joint, etc.). More likely the switch though since it is exercised mechanically way more often. Nice video Mike, thanks!
Thanks for the tutorial Mike.
Can you tell me what the transformer secondary output voltage is on those radios, I'm having some uniden washingtons sent over to Aus from the US and will need to replace the transformers for 240 volts.
Factory service manual shows transformer secondary winding is 15.5 VAC @ 4.5 Amps.
Thank you kindly.
Where did you find the replacement switch for this?
In my parts cabinet. I have several dozen NOS switches in stock.
i just had to change a power switch in a 2000 this week same problem radios showing its age
The engineers must have work at a plant the made All American 5 radios. The power switch was in the ground leg there.
nice radio,,, plug it in to 220v better receive and xmit LOL!!!!
You'd have a real flame throwing putting the fire in the wire radio then. ;)
I wonder if the power supply was goosed to compensate for the bad power switch....
Low voltage? nah.... just turn it up higher!
LOL, I didn't even consider that. Wouldn't surprise me in the least.