I think ground planes are more a factor of the wavelength of the frequency and not the vertical antenna length, and they should all be as close to 1/4w as possible. In the case of GMRS frequencies right around 460mhz... is ~6".
Thanks for offering your assistance
Thank you for you insight and knowledge.
The coil represents a tuned circuit, and depending on the frequency, will pass or block certain frequencies ranges. In the case of the standard dual-band, mostly considered VHF/UHF which is ~146mhz and ~ 440mhz respectively, the part of the antenna below the coil works at the higher frequency while the whole length of the antenna works at the lower frequency. GMRS is considered UHF.
I will be using the same antenna on my Midland MXT400. Never had one of the really short 'base loaded' antennas before. I've always ran whips, but getting the SxS.. I knew that was going to be a challenge running trails. So I'm gonna try it. (NOTE: I am going to carry 1/2w whips with me.. in case I need range.. get to a higher, clear spot, and swap antennas).
The RB3 off-road mount is very nice but is a bit expensive. Also the thru hole for the NMO mount was about 1/32” to small for the base to pass through it. It was easily fixed with a step bit but just mentioning it. Might’ve just been mine though.
Just looked at that... the NMO mount/cables I have are the 3/8" 'feed-thru' and not the 3/4" easy enough to change the angle bracket tho... I may for future necessity.... just use one of the double banded Axia alloys generic bar mounts and build my own angle. I ordered 3 of the single bands, to mount my radio mounting base plate on the front rops bar.
Contact them, I called their number and an actual human answered! In fact it was a very nice lady that was actually packing orders for shipping when I called. I get the impression they’re a machine shop making these on site. I’d be willing to bet they’d make one with a 3/8 hole. I can’t guarantee this but I’d be willing to bet they would. She was great to talk to and I believe she may have been the owner/co-owner of the business. Super helpful and friendly.
That’s the only reason I didn’t go with a ghost style. I like the look and small size but everyone says the same thing about impact regardless of model. That’s what steered me to the short whip style and opted for a spring base although I don’t think the spring is all that necessary or helpful but it’s there I reckon.
Just as an idea.... measure the diameter and check out some water bottles that you could cut to length. Many of them are poly carbonate and of course hard to break. Maybe set screw it to the remaining mount? Get your favorite color too, lol.
Thanks for the reply, trying to find an antenna that will work that is not mounted above the roof would be ideal, i don't have much room over head when i load it in the Toyhauler.
That looks well protected I would have never guessed it would have got broken there, but I guess that's just plain bad luck.
Any antenna will work mounted below the highest point on the rig but none of them will work to their peak potential. Regardless of antenna moving it down will decrease its capability. The question is will it decrease it enough that you will notice? That depends on your intended use. If your goal is to talk as far and as clear as possible the yes you may notice a difference. If your intentions are to talk to the other people in your group and you’re typically less than a mile apart I doubt you’ll notice a difference. Remember ALL two way radios operate on line of sight (skip not withstanding but that’s another topic) so anything between you and who you’re attempting to talk to will decrease the signal to some degree. Moving antennas higher just gives your antenna a “better view”. But your antenna will still work regardless of mounting location however your range can be slightly affected or maybe not so slightly depending.
The I.D. of Schedule 40 1.25" PVC conduit was almost the right size and a light cut in the lathe was all it took to make it fit the antennae base. Had a bunch of it on the shelf from the failed Starlink debacle. I plan to bond it together with 3M 5200 sealant.
