Midland MXT275 GMRS background noise

[TimWSGR360]

Hi,

I have a new Midland MXT275 mobile unit.  When I connect to my local repeater, I am told that there is feedback in my response and listeners can hear my engine rev while I drive.  I have tried to diagnose the issue by parking, turning the car off, but they can still hear feedback in my transmission.

 

[OffRoaderX]

That's not 'feedback', its noise, or engine noise.. or, ignition noise.. Feedback is a whole 'nuther thing.

what kind of car is it, does it have any LED lights, and how is the radio wired for power?

[WRUE951]

I remember those days, way back when. . My 70 Chevile played hell with my CB until i put in an electronic ignition    

[WRYZ926]

More information will allow us to help you better.

Noise can come from many sources. Alternators, spark plug wires. cheap LED lights, using an accessory port, wiring directly to the fuse panel, etc.

The best way to connect any two way radio in vehicles is to run the radio's positive wire directly to the positive battery terminal while running the radio's ground wire to a chassis ground. You do not want to use the battery negative terminal, especially on newer vehicles equipped with battery management systems.

[amaff]

11 hours ago, OffRoaderX said:

That's not 'feedback', its noise, or engine noise.. or, ignition noise.. 

It shouldn't be if they're still getting it with the engine off and just running off the battery. Could be some noise from lights tho, since seemingly every car turns the headlights on if you so much as walk too close to it

[WRYZ926]

It could be a number of different things causing the noise. Knowing what vehicle he is using and how it is powered will help. All of the LED bulbs and computer modules on newer vehicles can cause noise.

I had to put clamp on ferrite beads on the wires powering my radios and I even put one clamp on ferrite bead on each end of the main wire going from my alternator to the battery on my 2023 Ford Escape. I still get an occasional whine when transmitting. But it doesn't happen often enough to chase down the source.

Another thing people sometimes overlook are al of the LED street lights and LED bulbs used in homes. I know the cheap LED lights in my garage are very noisy on 2m, 70cm and GMRS. I don't dare try to use any 2m/70cm or GMRS radios inside the garage with the lights on.

Power transformers are another source of noise if they are starting to go bad and/or have bad connections. Solar panels are another source of noise.