so i've been running a little handheld clipped to my visor for like two years now and finally broke down and got a proper Yaesu FTM-400 for the truck. got it mounted under the dash on a RAM mount bracket, ran the power cables direct to the battery with an inline fuse which i feel good about, and threw a mag mount on the roof for now until i can figure out the permanent antenna situation.

overall it sounds way better than the HT obviously but i'm getting some engine noise on receive, like a whine that changes pitch with the RPM. i've read about alternator noise and ferrite chokes and all that but honestly im not sure where to start. the power cable is pretty close to some other wiring under the dash, could that be it? or is it more likely coming in through the antenna feedline?

also curious what people are running for antennas on trucks, i want something that'll survive the highway and maybe the occasional dirt road. the mag mount is fine for now but it slides around a bit when i make sharp turns which is kind of annoying.

the RPM whine is almost certainly alternator noise and yeah it's super common. first thing i'd try before buying anything is just moving the power leads away from other wiring if you can, sometimes that alone kills most of it. if not, a noise filter inline on the power feed helps a lot, the ones from West Mountain Radio or even the cheap ones off amazon work fine for this. some people also put a ferrite choke on the coax near the radio end and that can help if it's coming in through the antenna side.

for the antenna, if you want something that'll stick around on the highway i'd look at a lip mount or a through-hole NMO mount. mag mounts are fine for getting started but they really do slide, especially on a smooth roof. i've been running an NMO mount through the rain gutter channel on my old silverado for years and it hasn't budged. Diamond makes some good dual band whips that aren't too long and handle highway speeds fine. the NR770HB is what i've got and it works great.

oh man i had the exact same whine problem when i put my TM-V71 in my jeep, drove me nuts for weeks. turned out for me it was actually the ground, i had grounded the radio to a bolt under the dash that wasn't making great contact with the chassis. once i ran a proper ground strap directly to a known good chassis point it went away almost completely. might be worth checking that before you go buying filters and stuff.