Batboard

Hi, I have a MCS2000 VHF that has successfully been working a a medic unit for the past year. Yesterday i noticed when I hand the mic up in the ungrounded mic holder it transmits continously. When the mic is taken out it stops transmitting. Otherwise the radio works normally. I have tried 4 different mic's with the same outcome so it's definately the mic. It transmit's when the ptt is pushed and recieves normally as long as it isnt in the mic holder. Any Idea's of why its doing this?? Thankx

just a guess...
Some systems use the mic hangup clip to short between two contacts built into the microphone's hang up button on the rear of the mic. Typically this is used to put the receiver into PL mode. Since you have tried other (correct Motorola microphones) mics, there may be a short inside the radio between the wires that sense the hang up clip and PTT.

Try putting a coin across the button on the back of the mic and see if the unit keys up.

There may be a programming switch to disable this... have you made any programming changes lately?

I also wonder if maybe it's related to an emergency input on the accessory connector.

Sam

I thought the mcs2000's used the magnetic style for hang up, not the metal grounding style

The penny test was positive it keys up when inserted. No programming or any changes were made to the radio. It decided to do this on its own.I'm going to assume its a short of unknown nature then?