20 Most Recent Cobra 18 WX ST 40-Channels Base CB Radio Questions & Answers

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You probably have a damaged mic cord. These are not overly rugged. You might want to replace the mic cable with a quality Beldon mic cable.

make sure you have a good ground.

it may not be that IC but maybe a electritic cap or a transister.

spend the money you will use to fix it and buy a new radio.

check the speaker it may be dry rotted and not working.use an external speaker. depending on the time of day you probably couldn't reach any one any way Get a friend to talk on another radio while you listen and then let him listen for you.

to get this fixed is going to cost you more than the radio is worth. Your decision.

get another that only receives and no transmit.hook them up together .one on top of the other .I have a friend that did this and it actually worked

another splashbox D-11

start unsoldering you final , check it for proper voltage. then do the same for the driver. Check the voltage regulator. make sure you have the proper out put voltage in the vco section before doing anything. Also make sure you are on frequency.you more then likely have a short somewhere in the receive section and you are just going to have to break it down area by area , transistor to ICs .Its going to be painstaking but you will find it.

no ,black is for ground ,red is positive and yellow is positive ground but your radio will run with or without the yellow.

should never tune.they are tuned from the factory.Now peak thats different.The only thing you can do is turn the watts up or down and turn the mod vr up. you need a meter to do this.A schematic will also help.now have at it.

you have to have that led replaced by a tech

final or main IC getting ready to burn out.Have it checked by a tech.If its the final then replace the driver also.

Check your antenna. Make sure it is getting a proper ground. If mag mount; make sure base of antenna and where you put it are both super clean. Check where whip goes into coil or base. Make sure all allen screws are tight and whip is not either all the way down to the base or up to the top. If antenna is mounted; make sure that it has a good ground. You might have to remove some paint around the base to get a good connection. DO NOT TRANSMIT WITH A HIGH SWR. YOU CAN BURN OUT THE EXPENSIVE POWER OUTPUT TRANSISTOR. Hope it helps. Tom

www.cbtricks.com

change the reverse polarity diode. Put one in that is one number higher like 1n4003 to a 1n4004 .It will handle more volts so you shouldn't blow any fuses.

Sounds like a antenna issue. Make sure coax is in good order.and antenna is connected properly. You might have to get a "swr" meter to put in line between radio and antenna to make sure antenna is "tuned" to were the radio is operating. Radio shack sells a ok low budget swr/power meter.

The first thing to do is to check if your power wire actually has power to it. Do this with a test light or a multimeter. Given that the wire is powered, check to make sure your ground is good. Modern cars have so much plastic in them that grounds may be hard to find. The next step is to check the rig's fuse. Make sure the microphone is plugged in, too. If none of this helps, your radio needs repair or replacement.