Question about Uniden GMR638-2CK (22 Channels) 2-Way Radio

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Constant Rx Our radios have all steadily developed this problem but for no clear reason (Some have been dropped but this developed later. Whenever we turn them on they are constantly in receive mode. Showing Rx on the screen and with constant squelch (Really annoying!) Switching mon on and off doesn't help and there is no apparent internal damage. Any ideas? We have about 15 of the suckers in need of a fix and of course all are out of warranty........

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Re: Constant Rx

I have a UH036SX so not sure if its exactly the same. If you open up the unit, there is a large black potentiometer near the base of the antennae. I found if I wound this counterclockwise by approximately quarter of a turn with a small flat blade screwdriver it reduced the squelch level to a better level. I suggest wind it down until the static is gone, then increase slightly to give the best level.

Posted on May 25, 2013

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Re: Constant Rx

Hi, It would initially seem that your auto squelch is malfunctioning. With the squelch apparently way down, the RX indicator would automatically appear as if you are receiving something (even if it were just noise). Assuming no other fault except the auto squelch, a possible workaround is to use any of the 38 CTCSS codes both in receive and transmit. With the CTSS activated (TX/RX), even with squelch all the way down or auto off/defective, you will not hear anything except a radio transmission with the correct CTSS code. Again, this will only work of course with just the auto squelch muting problem. Any other problem/fault and this method may not work. Hope this be of some help/idea. Post back how things turn out or should you need further information. Good luck and kind regards.

Posted on Sep 03, 2007

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