Question about Cobra Mr Hh425li Vp Marine Hand Held Dual Band Transceiver

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My Cobra MR HH425LI don't transmit and received after 5 minutes

I have two Cobra MR HH425LI. After 5 minutes from power up, the radio stop to transmit or received.
On first 5 minutes all MR HH425LI work well (received and transmit ok with the same cobra radio and with other model).
After 5 minutes from power up, the radio stop to transmit or received.!!!:
When I press TX on the screen appared the TX indicator but I don't received anything on all other station on this chanel (on bouth band).
When I press Tx on  other model station (I have many other station) all MR HH425LI don't received the signal (but all other station receiv all ok).
When I press Tx on Cobra MR HH425LI other station don't received the signal.
If I power off the Cobra MR HH425L and Power Up this radio work ok again for only 5 minutes!!!

What can I do to resolvate the problems?
Thank you

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2 Suggested Answers

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SOURCE: radio sticks in TX mode after I let go of the button on the mic

Hello williamhicks,

There is a relay in side of the cb that might be sticking. The problem is that this situation might be environmental. You say that you sent it back to Cobra twice for repairs. I think that the place you are sending it to differs enough environmentally so that the problem does not manifest itself. You can test this by exposing the unit to different temperatures, to determine if the internal relay is sensitive to variations in temperatures.

If you do find that the relay has become tempurature sensitive, you can order the part from Cobra, or strangly enough from Radio Shack, since they do carry the same part just by a different part.

I hope this helps,

Thank you,


Posted on Mar 11, 2009

  • 35 Answers

SOURCE: cobra marine band radio will not transmit more

Before changing out the radio try the radio on a ANTENNA RADIO TESTER or try it on a different antenna. Good luck.

Posted on Jan 29, 2011

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