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Just remember, smoke signals are line-of sight!

A futile attempt maybe to save the battery it seems... 12.8 is probably just enough to float the battery once charged. 13.8 is a nominal level between float and a "cleaning" charge (with engine running in my rust bucket, my Icom ID-5100 shows 14.1V) I believe at float voltage, the plates can get fuzzy. I have had battery chargers that try to recover bad batteries by using up to 16V "shocks" to decompose the fuzz on the plates. It does cause thinning of the plates. The basic antenna is a half-wave dipole. It is considered a "balanced" antenna (so, properly to use with coax, one needs a balun to convert the balanced antenna to an unbalanced coax). It is half the wavelength at the frequency of interest and split in the middle -- which is where the feed line connects. For GMRS 465MHz (mid point of 462 simplex and 467 repeater) the wave length is ~64.5cm. A dipole would be ~32.25cm -- so each leg of the dipole would be ~16.12cm. This antenna form has a pattern that looks like a donut with the antenna rising through center of the donut. So signals are strongest perpendicular to the antenna, and essentially non-existent off the ends. When comparing antennas, a dipole is 0dBd (db relative to dipole) or 2.15dBi (db relative to a fictional point radiator "isotropic" which puts signals into a perfect sphere -- since such does not actually exist in nature, the energy going into parts of the sphere are "focused" by a dipole -- so more energy is "seen" on the perpendicular points of the donut as it gets the energy that would be off the ends). A quarter-wave antenna is basically one half of the dipole, so only 16.12cm long... BUT it needs a ground-plane to create a "mirror" of the missing half of the dipole, and maximum gain is probably less than the dipole as the ground-plane sort of reflects the signal in such a way that parts may interfere (cancelling out at some angles) and reinforce (adding in at other angles). I haven't actually studied how 5/8th wave works... by the numbers it is a half-wave with an additional 1/8 wave added to the top. Also, for vehicle/HT you are unlikely to see a true dipole, as the antennas are fed from one end. That also changes the behavior. Longer (yet tuned for SWR) antennas should show a gain over 0dBd as they squeeze the donut top/bottom -- pushing the excess energy further out on the perpendicular (but you may lose access of some mountain top repeaters as less of your signal is rising on an angle to reach them) I really should study my ARRL Antenna book again.

I’m a firm believer that placing the driver’s seat on the front bumper would result in more careful driving and less tailgating. ?

I ran a simple receive test with three radios that were off frequency by only 12.5Kc from the transmitter. The Wouxun "KG-935G" was able to filter out the off frequency station. The Anytone "AT-D878UVII plus" and the Baofeng "UV-82HP" both failed. Ken WQXQ522

According to the FCC Enforcement Database, since 2012, there are no ramifications. Unintended consequences include more "pure" spectrum-use since virtually every LMR radio is better designed and has far less spurious output than pretty-much any consumer GMRS radio on the market.

No one here was born knowing anything. We had to learn everything. We are here to help... so there are no foolish questions. Fire away. As mentioned above, the Nagoya NMO-200C (I assume that is what you meant) is not a half wave. It does require a ground plane. You can definitely add a piece of metal to create the ground plain. For best performance, you would want it to be round and at least 1/2 wave in diameter, about 12". 14" would be better. It needs to have a ground wire for best performance, sharing the same ground as the radio and antenna. However it's not 100% required. It will work better, though. Also, the top is an isolator, so the plate needs to be outside with the antenna. I would use a mix of 60 lbs double-sided Gorilla Tape (for instant hold) and RTV (for extended hold) if you don't want to use nuts and bolts to hold it down. I know I wouldn't cut into my top. It's critical to keep in mind that if you put a ground plan on the roof and put a fixed or mag mount antenna, regardless of the way you attach the ground plan, it is not going to hold a very heavy antenna. Highway speeds will eventually rip it off or the top may fail, if you have a heavy antenna or something with high wind drag. If you had a 1/2 wave antenna, a ground plane would not be required. As far as a lip mount that can attach to the swing gate, I have have several JK's... 07, 08, 10, 3 2013's, 14, 15 and 16... every one of them had either a Diamond or Comet lip mount. I prefer either the Comet RS-730 or the Diamond K400 with the appropriate antenna connection (based on your antenna choice and mounting type). Be sure to install the mount on one of the top corners of the swing gate, so the antenna is an appropriate distance from the spare tire and carrier. I used to put mine all the way on the passenger's side (about 2"-3" away from the edge) adjusting it so it clears the glass when you open the back window. This kept it away from the window wiper motor and the spare tire and carrier.

At least 7 inches, but try to avoid the first 3 even multiples of 7. After 2 feet, it doesn't matter. If you want to have them on at the same time and be able to use one without turning the other off, put them as far apart as possible.

You aren't missing anything. It works. You can position it at any angle you want. It's a 3 axis.

Well... while it has "3 adjustment" points, it still doesn't allow rotating the NMO plate to the outside.. To avoid possible interference with top of hood if the lip to top distance is more than the mount lip-to-NMO plate, you'd have to tilt out at the bottom hinge moving the NMO plate away from the hood, then tilt in at the top hinge to set the antenna vertical. The Diamond allows you to rotate the top hinge and NMO plate so it sticks out on the side with the "support tab", and then use top hinge to lift the plate for vertical antenna. The design worked well on my 1999 Jeep Cherokee, since the tailgate window sloped, and then the tail gate was vertical -- I could mount to the side of the tail gate just below where the slope/vertical transition, rotate the plate and tilt it to vertical, with the plate away from the body. The window slope meant the antenna was further from sheet metal (this was a screwdriver HF/6/2/70 rig). Pity the Jeep rolled over on a damp off-ramp. Other than some kinks in the whip, I think the screwdriver survived, but we lost a few of the remote mounting screws stripping it before the junk yard got it.

Thank you I definitely read every word, and I appreciate others that are willing to share knowledge with those seeking it. I believe you have helped me out on the JT forum as well. I appreciate you. I'm not drilling holes either.... I will reach out once I finally find what I am looking for and get it finished . Thanks again.

This page has some useful charts when going the physical separation route: http://www.repeater-builder.com/antenna/separation.html A good duplexer should give you more than 80dB of isolation (100dB+ if you get a really good one and take forever to tune it).

Welcome! In some ways GMRS repeaters are more defined than ham repeaters. GMRS repeaters should always receive in the 467MHz frequencies and transmit at 5MHz lower, where the offset for 2m repeaters can be positive or negative. Also, the frequencies are specifically defined as channels. The repeater database here is very helpful. Repeaterbook is too, but doesn’t have as many repeaters as the MyGMRS database. I hope you like it here.

https://www.hamradio.com/detail.cfm?pid=H0-003079 (short coax, the longer coax model is out-of-stock at the moment) Don't think I'd recommend https://www.hamradio.com/detail.cfm?pid=H0-006521 as it doesn't seem to allow rotating the lower hinge. Once you've mounted it and hinged the antenna to a vertical, the mount might be hitting the hood if the rise isn't sufficient to clear. Rotating the lower hinge would let you put the offset to the outside, away from the hood. The K400 allows rotating the lower hinge, and then pivoting up to vertical. https://www.hamradio.com/detail.cfm?pid=H0-006551 (hah "does not damage expensive or leased vehicles", yet most of them want the under-lip set screws to make contact with bare metal so one has to scrape small dots of paint off from the underside ? Has same problem as the previous.

TL;DR is internet slang for Too Long; Didn't Read. It's kinda funny. I see what you mean about the mounts. While they will work (as you're seeing) they just aren't ideal. The one I use isn't ideal either, but it allows for much better performance than the one you're currently using. The best involves drilling big holes, which I'm not doing. Good luck! Looking forward to seeing what you get installed. Yeah, 14 is too small if you are going more than a few feet. When I had my MXT500, I cut the factory wires off and replaced them with 12, and 45 amp power pole connectors.

@WRUF442 the antenna height you mentioned indicates that it is a half wave antenna and should not need a ground plane. Also, if you are good with cutting a hole in the roof, just put the mount directly in the roof. If you switch to an antenna that needs a ground plane, that aluminum roof panel will do just fine. @wayoverthere and @KAF6045, you don't need 6 feet... the safe power density at 50w FM 100% duty cycle for 5 minutes is 1.55 mw per cm squared. That is only about 3 feet. But I don't know anyone getting a full 50w out of a no gain antenna and I don't know anyone who is keying full power for 5 minutes either. Most people with 50w radios and a no gain antenna see about 32-35 watts. If you calculate for that, plus 2 minutes of exposure and a 50% duty cycle (2 min on, 2 min off is more realistic), now your safe distance is about 1.5 feet. Of course, the further away it is, the safer you are. Just wanted to point out numbers based off of more realistic usage.

Minor correction: There is still much in California that is not trunked and not encrypted. Non believers can watch this video to see what I get on my UV-5R (and other analog radios): --> https://youtu.be/z9FM0nQW4lw

Hello all, new to GMRS (like as of yesterday) but not new to radio. Been a ham since 1996. Did not have any idea that GMRS was as big as it was with using repeaters, etc. Still trying to learn how to use the freqs and how to call people and access repeaters. Definitely not as defined as ham so any help would be appreciated.

The answer to your question is "NO" .. Weird that after so many words, the question still had not been answered.

338538504_ActiveGMRSRepeatersInMaine-2022-08-10.pdf 2022-08-16 - Active Maine GMRS Licenses by Call Sign.pdf 2022-08-16 - Active Maine GMRS Licenses by Name.xlsx

Welcome

Welcome, Subject to topography, you should be well within the range of the Johnstown repeaters. WRDB702 - Jim

Forgot to mention..Thanks for reminding me... Always beware of the "some people" that try their best overcomplicate everything.

I agree.. I have put one up, and am [partially] responsible for getting a 2nd one up, covering most of Southern California.

I think a good lawyer would argue that proprietary encoding is not encryption. Encryption is intentionally done for the singular purpose of concealing the meaning of messages. A proprietary encoding scheme makes it very easy to decode the messages; you just have to buy the interface.