Help with a motorhome CB

[Milan]

I have a Magnum S9 in a Class A motorhome. The radio worked before I installed it in the motorhome. It was in my work truck before I retired. Once I installed it I noticed I was only receiving. When I would transmit I sounded garbled and like I was on another channell. I sent the radio out to get fixed. I was told it was out of tune and the mic was bad. He tuned the radio and sent it back. I bought a new mic. Had a friend park down the street about a 1/4 mile away. Anutime he would talk all I got was a buzzing sound. When I tried to talk all he got was a buzzing sound. Maybe a bad new mic?

[1iwilly]

so you send the radio get work on get it back now is worse sound like you need to go back to basic check coax check ground on vehicle priority check SWR also voltage to radio this is just a starting point

[Milan]

so you send the radio get work on get it back now is worse sound like you need to go back to basic check coax check ground on vehicle priority check SWR also voltage to radio this is just a starting point

Coax is good. SWR under 1 channel 19. Not sure how to check for voltage. Turn the radio on it comes on. Tested mic on a friend's radio it works just fine. Will mount my radio in his truck on Thursday, will see if it acts any differently.

[Radiohobbyist]

If not already, try running a dedicated power circuit (Positive and Negative) straight to the vehicle battery, with fuses on both Positive and Negative at the battery, and another on Positive near the radio. Orient this wiring away from vehicle instruments, computer/data lines, motors, etc. Next, connect the radio housing to the vehicle chassis with flexible braid.