Why does mic stay open all the time on my rugged radio in my atv

perhaps the squelch is set too "open". Try to program a tone code into the radios. Many times the manufacturer expects you to use a tone and they set the squelch too high, or open. This causes the squelch sound because the radio is trying to pull in weaker signals. If you are using a tone code, the model of the radio is needed to tell you if the squelch can be adjusted.

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.

Your mic has a series of contacts which cut off the speaker before you transmit and activate the transmitter. If the mic has screws holding it together. With the radio power off. Open the mic and check the spacing between the contacts if it is not enclosed. Some are sealed in a casing. You want to verify that the contacts are not sticking or too close together allowing other functions to stay on.

If you cannot check the contacts. Unplug the mic connector. Get a copy of the mic wire functions and use an Ohm meter to verify that the speaker leads disconnect when the mic button is keyed. It should read "0" when the mic button is pressed. If not, then there is a problem in the mic button switch and you will need a new mic.

Carefully inspect the mic cable for wear breaks. The wires inside are easily damaged when the shielding is damaged. Cables can be repaired. Be sure to slide on two to three shrink tubes to cover the repair job when done. Slide on the tubes and heat them one at a time to create a good protective shield for the wires. This involves several solder connections which will need a small shrink tube on each wire solder. Electrical tape can be used but it will end up a large bulge in the cable afterwords. This should be considered a temporary repair since the strength of the mic cable will be compromised. Stretching the cable afterwords can result in a wire break.

Next check the connector where the mic attaches to the radio, Often there are two small screws which can be removed so you can check the wire connections. A lose wire may be making contact with another contact when the mic is moved around allowing the speaker to stay on during transmit. A small lose strand of wire will account for the noise. After a lot of use the contacts in the plug can become lose if you frequently stretch the cord pulling on the connector. If it is the problem make a note of the wire positions. Then remove the leads with a solder iron. Be careful not to overheat the small metal post as the posts are seated in a plastic mold which can be damaged when overheated. Slip shrink tubing onto the mic cable. If the clamp was not very snug use more than one piece of shrink tubing. Cut off the bare ends and strip back about a 16th (just enough to solder back on). Re-solder the fresh wires to the pins. Over time the wires going into the solder weaken and break. Make sure there are no lose wire strands which could touch another pin. Slide down the shrink tube as far as possible and heat with a match or lighter. Re-attach the clamp so that it holds the cable snugly.

If the problem is not in the mic switch, cable or connections, you will need to take the radio to a technician.

You can also check for mic related problems by using a known good mic. However it should be for the same model radio. Pin numbers and configurations vary between radios, even the same brand of radio. Just because it fits the connector does not mean it will work properly and can even damage the radio.

check the mic connector internally its probably touching something in side.

Replace the Keying diode. you can sub it with two 1n914 in series..

Yes the light will stay on and change when you key the mic

Make sure your antenna is tuned properly. The light comes on when the SWR is too high. This damages the final transmission transistor. You can blow the transmit in the radio.

If you need to tune your antenna and do not know now, go here and follow the instructions...

tune SWR

there could already be some damage to the final transistor already, it may be why the light stays on. Tune the antenna according to the article and then if the light stays on again, there may be something wrong with the radio, or the warning light is not adjusted correctly.

If your swr is okay, then turn vr6 all the way down so the light does not come on.

Try pulling the mic out to see if it stops if it does you have a problem in the mic if not it
is inside the radio.
Good luck

What happens if you "key up" and "let off" and the transmitter "hangs", you remove the microphone plug from the Cobra ?
Will it still be transmitting or will it stop ?
If it stops, the problem is in the microphone with a "hanging" switch which you can easily clean or replace.
Iif it keeps transmitting while the mike is disconnected, there is a problem with the Rx/Tx switching circuit. This needs further investigation by use of a circuit diagram.

Hello scooter 34 1,

Are you able to get a new mic for your radio? Because I really think the problem is in the mic. Here is a test buy a cheap replacement mic that can be used with your unit and swap it out with your current mic. 9 time out of 10 this will solve the problem. If not the problem may be with the sensor switch inside of the unit itself, the sensor switch detects when the mic is activated, it avoids the galvanic response of the metallic switch in the mic. The switch could have malfunctioned. However I repeat, that I believe the mic has malfunctioned.

I hope this helps,

Shuttle83