so anyway i finally got it working after about three weekends of messing around and thought id share what tripped me up in case anyone else is going through the same thing. i put a Yaesu FTM-300DR in my truck and it sounds great now but getting there was kind of a pain.

the biggest thing that got me was the power connection. i ran the power leads straight to the battery like everyone says to do and the radio worked fine but i kept getting this weird buzzing noise that changed with engine RPM. turns out one of my ground leads wasnt making great contact under the seat where i had it bolted. spent two hours chasing RFI and it was just a bad ground the whole time. once i cleaned that connection and used a star washer it went completely quiet.

the other thing was antenna placement. first i had a mag mount on the trunk lid kind of off to one side and the pattern was all weird, uneven signal reports depending on which direction i was driving. moved it to the roof dead center and it made a noticeable difference. probably obvious to most people but i didnt think about it much at first.

anyway if anyone is just starting out with a mobile install, take your time with the grounding, it really is as important as everyone says. whats everyone else running for mobile antennas these days?

yeah the alternator whine thing gets almost everybody at least once. i remeber spending a whole saturday convinced my radio was defective before someone at the club pointed me toward the ground. classic.

im running a Diamond NR770HB on a lip mount on the trunk of my honda and honestly its been rock solid for a couple years now. lip mounts get a bad rap sometimes but if you do them right they work fine, the trick is getting a solid ground strap from the mount to the body because the paint breaks the electrical connection. some people run a short piece of braid from the mount down to a bolt under the carpet and that does the job.

for what its worth i also ran a dedicated 12v line all the way from the battery on my FTM-400 and used an inline fuse near the battery and near the radio end. belt and suspenders approach but i sleep better knowing its done right especially with all that current draw on transmit.

nice write up, this is basically exactly what im about to do. just got my technician a few months ago and ive been running HTs but want to do a proper mobile setup in my jeep before winter. was already planning to do the battery direct connection so good to know about the grounding thing ahead of time.

quick question if you dont mind -- did you need to do anything special with the head unit mounting since the FTM-300 has the separate head? i have kind of limited dash space and wondering how people handle that.