2022 Ram 1500, Baja Design LED lights, positive lead is off an IGN fuse tap (primary circuit is 20amp, fuse tap is 15amp to radio), negative is on a chassis ground, happens on both engine on/off, the PL259 connector is crimp (0.213/0.068 dies) with a touch of solder on the tip.
There's at least three things I can see going on here:
1. Proximity of the antenna to the lights.
2. Power source
3. Noisy LED lights.
Here's what I'd suggest. It's going to take some work, but it'll pay off in the long run.
Two way radios need clean power. Tapping into any existing wiring/fuse is not a good plan, as it shares the circuit with other noise making devices.
Not sure if you were saying your lights and radio are on the same circuit, but if it is, that's not a good plan, either.
If you are going to be keeping this truck, put some time and effort into pulling radio power off the battery. This will give it a clean source of power that will fix some of your issues. The positive power for the radio should come off the positive terminal on the battery. Install a fuse or circuit breaker as close to the battery as you safely can. Run the positive power lead to the radio with no breaks, splices or other connections. You want the radio on its own circuit.
Running the negative to the vehicle body is the right way to do it.
Sounds like you tapped an ignition switched circuit, so looks like you want the radio to power on/off with the truck. That's fine, you can use that ignition switched circuit to drive a relay that interrupts the power to the radio. That will isolate those two circuits, giving you ignition switch control as well as clean power off the battery.
I'd do something similar with the LED lights. While they usually don't draw much power, some of them are really noisy, and tapping them off existing circuits will end up putting all that noise onto the original circuit.
Run a positive lead from the battery -just- for the lights. You can run a separate relay to give you your ignition switch control.
If you plan on adding more accessories to the truck, upsize the wire now, it's much easier to do it once than doing it twice.
For multiple radio installations (If you ever want a CB radio along with the GMRS radio), run a larger wire from the battery through a fuse/breaker, and then to the cab. Install a fused distribution block that will allow you to install more accessories later by just connecting to it and installing a new fuse. Makes life easier in the long run.
Same for your lights. If more lights are in the future, a larger wire will allow you to grow without redoing the entire install.
Having the lights on their own circuit will help with the noise. But some LED lights are just noisy.
Next, lets discuss that antenna install.
The antenna is the most important part of your radio installation. You want the antenna up as high as you can, on a large flat metal surface (ground plane) and well away form any noise sources. From your description, it sort of sounds like you have a light bar above the windshield and the antenna mounted on or near that.
I'd strongly suggest redoing the antenna installation. Put the antenna on a permanent NMO mount dead center on the truck roof. Yes, that will require drilling a hole, but it's well worth it. Having the antenna on top of the truck and in the center will give you the best performance possible. Anything less than that is a compromise. What that will do is put the antenna high on the truck, giving it the best view in all directions. Center of the roof will give it an ideal ground plane, which will help it work equally well in all directions. By having your current antenna installed on the A pillar, you are creating a directional pattern that is throwing most of your signal to the front left side of the truck.
This will also move it away from the LED lights and get the coaxial cable fully routed inside the vehicle where it is protected.
It really is worth putting that extra work into the antenna installation. It's not hard to make these GMRS radios shine with a good antenna mounted in the right location. Unfortunately many mount them where its easiest and never realize the improvement they'd get with a bit more work.
Also, if you do have plans to install a CB down the road, that would be a good time to run a second antenna mount for the CB antenna.
