anyway everything powers up fine and i can hit the local repeater no problem on 2m but when i checked SWR on the 70cm side its sitting around 2.5 which seems high. the antenna is a Diamond MR77 which i thought was supposed to be a decent dual bander. coax is about 12 feet of LMR-240 with PL-259 connectors that i soldered myself. im wondering if maybe i messed up one of the connectors or if the antenna needs some kind of tuning which i didnt think it did. havent had a chance to pull the antenna off and check the connection at the mount yet. anyone dealt with this before

problem is ever since i did the proper install im getting this weird buzzing noise on receive that kind of pulses with the engine rpm. didnt have it before with the janky mag mount setup which makes no sense to me. transmit seems fine, people say i sound good. its just annoying as heck on receive especially on 2m simplex where there's not a lot of signal to cover it up.

anybody dealt with this before? i'm wondering if its the alternator but i dont really know how to chase that down. the power leads are pretty close to the engine harness where they go through the firewall, maybe thats it?

The noise floor is so much better than i expected honestly. Was worried about alternator whine but i think doing the direct battery run helped a lot. I did have a weird issue where the radio would reset when i started the truck but that turned out to be my ground wire being loose at the chassis. Like really loose, embarrassingly loose. Tightened it up and haven't had the problem since.

Only thing i'm still figuring out is antenna placement. The lip mount puts it on the rear hatch which opens obviously so the coax has to loop a bit. Works fine but wondering if anyone has dealt with coax wear over time with a hatch like that. Using the factory coax that came with the antenna for now.

antenna is a Diamond NR770HB on a mag mount right now, sitting on the roof. the coax is just routed through the door seal temporarily. im using RG-8X for the run which is maybe like 8 feet total. the power leads are about 5 feet on each side and i havent done any ferrite chokes yet because i wasnt sure if that was actually necessary or kind of overkill.

has anyone dealt with this? wondering if i should start with ferrites on the power leads or if the coax routing through the door is actually causing some of the issue. also not sure if a mag mount is even a great ground plane on a modern truck with the plastic bed cover situation im dealing with

when i'm transmitting, especially if the truck engine is running, the guys on the local repeater keep telling me they hear a whine or buzz in my audio that kind of changes with the RPM. i've read a bit about alternator noise and i think thats probably what it is but im not totally sure how to track it down or fix it. i ran the power leads directly to the battery with an inline fuse like everyone says to do, so i thought that would take care of it

the antenna is a nagoya NMO mount through the roof, coax goes down the A pillar and under the carpet. everything looks clean to me but clearly something isnt right. has anyone dealt with this before? is there something obvious im missing

But I'm concerned about clearance issues with my garage and low branches. The fender mount seems more practical but I'm wondering about the performance trade-off. Anyone have real-world experience comparing these mounting locations?

ive seen some people do the trunk mount thing and run just the head up front and it looks really clean but im nervous about the cable run and whether ill lose any audio quality or have interference issues with all that extra wire. also not sure how to route the power if the radio is in the trunk — do people just run a dedicated line all the way from the battery back there or tap into something closer?

anyone done this on a smaller car and have opinions either way? im a general class if that matters, mostly do local repeaters and some simplex when im out hiking spots to check conditions.

anyway the radio seems to work fine, hitting the local repeater no problem, but i'm getting this weird alternator whine through the audio that gets louder when i rev the engine. ive seen people mention ferrite chokes and stuff but im not really sure where to start. also wondering if my antenna placement is ok — its kind of toward the rear of the roof, maybe 8 inches from the back edge. wasnt sure if center would have been better or if it matters much on VHF. any help appreciated, still pretty new to mobile stuff.

Planning to run power directly to the battery with proper fusing. Any other gotchas I should watch out for on a first install?

the problem is i really dont want to drill through the roof if i can avoid it, not because im scared of it exactly but this truck still has payments on it and i just feel weird about it. ive been looking at the lip mounts that go on the rain gutter area but the F-150 doesnt really have a traditional gutter so that complicates things. someone at the club mentioned a stake pocket mount in the bed but id be worried about the antenna being back there and the ground plane being weird.

what did you end up doing on your truck or SUV, and did the location actually matter that much for everyday VHF/UHF use around town and hitting repeaters? im not doing anything exotic just local stuff and maybe the occasional simplex

anyone have experience with trunk lip mounts on a car with a short trunk? my trunk lid is pretty sloped so im not sure how well it would clamp on. also curious if theres a ground plane issue i should worry about since the antenna would be off to the side instead of centered on the roof. i know in theory centered is always better but figured id ask people who have actually done this in the real world.

right now the coax is just coming in through the door seal which i know is terrible and probably killing my signal or at least gonna wear through eventually. the radio itself is mounted under the dash on the passenger side and works fine, hitting the local repeater no problem, but i want to do this right before winter. anyone done a clean route on a newer F-series or just trucks in general — does the firewall grommet trick actually work without making a mess

roof mount would obviously give me the best ground plane and radiation pattern but im a little worried about running the coax through the headliner, my truck is a 2019 F-150 and theres a lot of stuff up in there apparently. trunk lip mount seems way easier to install and i wont have to mess with the interior panels but ive heard it can mess with the pattern on the side where the trunk is? or maybe that doesnt matter as much as people say, i honestly dont know.

using it mainly for local repeaters and maybe some simplex out on trail runs with the jeep club. not doing anything crazy like EME or anything where i need every last db. just want reliable comms. anyone been down this road with a similar setup?

anyway everything works, im getting out fine on 2m and 70cm, but theres this low hum in the audio that changes pitch slightly when i rev the engine. i know this is probably some kind of ground loop thing but ive messed with the ground connections twice now and it hasnt really changed. the hum is there even when im not transmitting so its not RF getting back in or whatever. its more of a receive thing.

anyone dealt with this before? i feel like im missing something obvious. the radio is powered off its own dedicated run so i dont think its sharing a circuit with anything sketchy but who knows

my main thing is where to put the antenna. i was originally thinking trunk lip mount with a mag mount style but someone at my club said roof center is way better for the radiation pattern on VHF/UHF. that makes sense to me electrically but i really dont want to drill into the roof if i can avoid it. the truck is still pretty new and honestly the wife would kill me. NMO on the trunk lid seems like the compromise but then im worried about the groundplane being weird since the trunk lid isnt connected to the chassis the same way.

anyone done this on a pickup or similar? worth just doing the roof and living with the hole or is there a good trunk lid solution that actually works well?

The thing is this truck still has that plastic body trim around the roof edge and im not 100% sure where the best spot to drill would be. A buddy of mine said the cab roof center is ideal for VHF/UHF but I've also heard people go through the trunk lid or even the fender. On a truck I guess that would be the bed? Im also a little nervous about drilling into a brand new vehicle if I'm honest.

Anyone done a proper NMO install on one of these newer F-series trucks? Is it really noticeably better than a quality mag mount like a Larsen or Comet? Or am I overthinking this as usual.

the antenna right now is a mag mount NMO on the roof toward the back. i know mag mounts arent ideal but i havent wanted to drill yet. wondering if anyone has dealt with this on a pickup specifically and whether moving the antenna further back toward the cab-over-bed area would help or if this is more of a grounding issue. the truck has the composite bed liner and i wasnt sure if that matters for ground plane stuff.

also my SWR on 2m is fine, reads under 1.5:1, so i dont think its the antenna itself. just something feels off about the installation and i want to clean it up before winter.

the big thing that was killing me was the power cable. i had run it through the firewall but i was tapping into a fuse block under the hood instead of going straight to the battery, and apparently that was introducing enough noise to drive me nuts on receive. switched to direct battery connection with an inline fuse and the difference was honestly night and day. i can actually hear the repeater now without that buzzing behind everything.

also the mag mount placement matters way more than i thought. had it on the rear corner of the roof at first and was getting a ton of multipath garbage on 70cm especially. moved it closer to center and things cleaned up a lot. probably still gonna drill eventually but wanted to get a feel for the radio first.

anyone else run that Diamond antenna? curious how people like it long term, specifically whether the SO-239 connection at the base holds up or if it gets flaky over time.

the audio from the speaker is just terrible when im moving. like at a stop it sounds fine, clear enough, but once i get moving above maybe 30 mph theres this low hum that gets worse the faster i go and honestly its pretty hard to hear people talking over it. ive tried moving the radio around a bit, checked that all the grounds seem tight. not sure if its the alternator or road noise or what. anyone dealt with this before? also does the mounting position of the control head matter for this kind of thing?

background: FT-7900R mounted under the dash of my f150, NMO mount through the roof with a Tram 1185 dual band antenna. grounds look good, i used the chassis ground near the mount and ran the power directly to the battery with the recommended fuse close to the battery terminal. been pretty happy with it overall.

the issue is when i key up on 70cm i get this buzzing in the audio that kind of pulses with engine RPM. classic alternator whine i guess? but here's the thing — on 2 meters it sounds totally clean. no noise at all. only on 440. ive read that UHF can be more sensitive to this kind of thing but i dont really understand why it would only show up on one band and not the other. is this a filtering issue or could it be the antenna or feedline? running LMR-400 which seemed like overkill for a mobile but i had a bunch of it left over from another project.

anyone dealt with this before? kind of at a loss here

Thing is when i do an SWR check on 146.520 it comes back fine, like 1.2:1 or something close, but on the 70cm side around 446 it's reading closer to 2.5 or 3:1 which seems too high to me. I checked the connector and it looks fine visually but maybe i did something wrong with the PL-259? Or is this normal for a dual band whip and im just overthinking it. The radio works and i can hit the local repeaters on both bands but still bugs me.

Anyone dealt with this before or know what to check first

the thing is it doesnt lose the signal entirely — i can still see the squelch light doing its thing on the display, so its receiving but just no sound coming out. then a few seconds later it comes back like nothing happened. its mounted pretty solidly i thought, used the standard bracket and its not rattling around or anything. anyone dealt with something like this before? im starting to wonder if its internal, like a cold solder joint somewhere inside the unit itself. radio is maybe 5 years old, bought it used.

the problem is when i key up on 2m everything sounds fine to me but people are telling me they hear a buzzing or whining noise in my audio that kind of changes with engine RPM. i've heard of alternator whine before but i thought running direct to battery would mostly fix that. the coax shield is grounded at the mount but im wondering if maybe the lip mount isnt making great contact with the truck body. or could it be the audio cable from the radio? i ran everything pretty close together which maybe was dumb.

anyone dealt with this before? kinda at a loss here

the head unit is mounted on a RAM mount on the dash which i'm pretty happy with, ran the cable through the firewall which was honestly the most annoying part of the whole thing, took me like an hour just to find a decent grommet spot. power goes straight to the battery with an inline fuse which i know is the right way to do it but crimping those ring terminals in the engine bay was not fun.

antenna is a Tram 1185 on a mag mount for now, eventually want to do a proper lip mount or maybe NMO through the roof but not ready to drill holes yet. and i gotta say the difference between this and the HT is just night and day, i can hit repeaters i could barely scratch before and the audio is so much clearer. anyway if anyones about to do a similar install and has questions feel free to ask, i made plenty of mistakes so i can at least warn you what not to do lol

anyway got it done last weekend. ran the power leads directly to the battery with an inline fuse, used the split mount so the head unit sits on the dash and the main body is tucked up under the passenger seat. coax goes up through the firewall and up the a-pillar to a NMO mount i had drilled into the roof. put a Tram 1185 on there for now, figure i can upgrade the antenna later.

first real test was driving around for about an hour hitting the local repeaters and honestly the difference from the handheld is just night and day. no more dropped audio, people can actually hear me clearly, its just... better in every way. wish i had done this sooner tbh.

only issue i ran into was the head cable was just barely long enough to reach where i wanted the control head. anyone else run into that? wondering if there are extension cables available or if i just have to live with the routing i have now.