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Neither. the concept of fixed is really orthogonal to the temporary/permanent axis. Of course, philosophically speaking, everything is temporary. However, there is a clear difference between in motion and not-in-motion. Clearly a repeater cannot be used while in motion. In this case I'd take fixed to mean it will remain stable at its location while it is supporting whatever activity it is designed to support. When that ceases, it will move on. Probably the edge case would be a mobile repeater that was only turned on when the vehicle in which it was mounted was parked. I.e. not in gear and the parking brake set. Such might be the case for some kind of shopping trip, treasure hunt, etc. I'd ague that was also fixed, since it did not move while operating. In any case. I suspect on the FCC's enforcement priorites list, tracking down borderline "fixed" repeaters ranks slightly below use of Part-90 equipment on GMRS.

95.1 The General Mobile Radio Serv- ice (GMRS). (a) The GMRS is a land mobile radio service available to persons for short- distance two-way communications to facilitate the activities of licensees and their immediate family members. Each licensee manages a system consisting of one or more stations. GMRS is not a hobbyist service, it is not for expanding ambitions, it is not a place to push the state of the art forward. However, there is a place for that... Amateur Radio. Per the FCC, Part of the Basis and Purpose of amateur radio is the: Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art. If those are your interests, get an amateur license.

I've said it before and I'll say it again, you can't do a vehicle-installed repeater. Repeaters must not be capable of operating while moving, and cannot have a mobile operation mode. It's written in the Part 95 definition of a repeater station. They must operate at a fixed position. The specifics of what defines a fixed station is a question I'm trying to raise to the FCC's attention. There's no spectrum entering or leaving GMRS. Consider frequency availability in the cities. Public safety is still building out on T-band here around Los Angeles because there is no spectrum available on 700 MHz, 800 MHz, or 450-470 MHz. Frequency reuse on those three segments is intense. Likewise, there's a lot of frequency reuse and congestion on GMRS, and coordination is necessary to protect against interference. In the suburbs out of the coverage areas of the cities, GMRS appears unused. Likewise, T-band and 800 MHz also appear unused. That doesn't mean there aren't any users. You just can't hear them, especially from ground-level. FRS users can exit receive range after a few thousand feet; low-level repeaters typical of private use can exit range in a few miles. Same goes for simplex or building-mounted repeaters in Part 90. The FCC won't deallocate 452.600 because they didn't hear anyone at their Denver field office in the last 25 minutes. For that same reason, they won't deallocate 462.600. Since there's already a lot of Part 95 462/467 MHz equipment out there in a poorly regulated (relative to Part 90) fashion, getting FRS and GMRS users to stay off those bands would be impossible. Removing FRS or GMRS would also kill an industry of unlicensed two-way radio manufacturing (which is a bigger industry than you think), threaten emergency preparedness for what is easily hundreds of thousands of people, and provide very, very little benefit to the FCC. Trying to change the service to illegalize the operating modes of the existing radios is too monumental a task, and is one of the reasons why FRS gained the 8 repeater output channels. The pressures of the license-by-rule system on FRS and fixed channel set of GMRS would actually favor expansion of the band over contraction. Setting up a bunch of repeaters blindly across all 8 channels just creates a bunch of interference for the other licensed users of the bands. Just because a repeater is open doesn't mean it isn't interference. This applies moreso during emergencies. Packing a bunch of users into GMRS in an attempt to lead the FCC to believe an already alive service is still alive doesn't make any sense. Setting up a bunch of repeaters in that close of proximity both in frequency and in physical space would also create intermodulation problems, further polluting spectrum. If you want to use wide splits and/or tiny mobile repeaters with appreciable output power, use Amateur spectrum in either a wide split on 70cm or crossbanded to 2m/900. That spectrum has already been made available for hobbyist use. GMRS isn't supposed to be a tinkering band, type certification tries to ensure equipment already works when it reaches GMRS spectrum. Amateur is also free from frequency coordination concerns on temporary setups, restriction on mobile duplex operation, and linking concerns. Cavity filtering only costs about $100, and considering there's a transmitter and receiver sharing an antenna, skimping on filtering isn't a good idea. Trying to implement a miniaturized filter would cause greater harm with receiver desense than benefit from running high transmit power, and with the filter order you need to get acceptable isolation even at 10 MHz, you're gonna spend more in component cost and tuning labor than you will buying a sixpack cavity filter. Single-channel repeaters don't cost much more than $400 to build ($100 cavity filtering, $75 transmit radio, $75 receive radio, $100 repeater controller and interface; power supply and antenna fill the balance). Performance isn't great, but it's certainly acceptable. Getting the cavities tuned is about knowing the right people or knowing enough theory to make cheap tools work (such as SDR + noise generator). Knowing a friend with the right tools is the right path to take, since they'll know more about the nuances of making a repeater work well. Building your first repeater alone isn't something I'd recommend, they aren't plug-and-play solutions and there's a reason this stuff costs money.

I was describing a legitimate use of gmrs radio. Not necessarily to pursue elk but to coordinate the recovery of a downed animal (up to 750 lbs after field dress. But also to "find" hunting friends who have become CONFUSED about where they are.) ( lost). I was inquiring if this use of a repeater was legitimate as it is only used at camp. Is a fixed location temporary or permanent?

My hunting trailer started life as a 16 x 7 ft enclosed insulated cargo trailer with windows. Power is 4, 6 volt pallet jack batteries connected parallel over series. 4 100 watt solar cells on roof. 4K cummings generator with 40 gal tank. (Mounted on flatbed 1 ton truck ) Radios in trailer, CB and GMRS. GMRS is a $400 dollar repeater made from two Motorola mobiles in a suitcase ( ebay). Every one we hunt with uses Btech gmrs v1 radios or the Betech 82hp. Having a repeater parked on top of a ridge gives solid coverage to both valleys on either side. As this is a trailer it is not used while moving. I belive this makes it a FIXED location while in use. (Hunting elk western Wa. State.)

I might suggest a little program, I think is still available for windows, if not there are others. ScanRec is a configurable recorder with vox for the PC, and you can run your radio into the sound card and monitor a channel for a week or a month....then just go back and see how much traffic was there when you play the recording back. In commercial radio, I have used a vox tape recorder to do this in the past. And, while I am telling stories...A tech I once worked with, he had an analog clock hooked up in the mix, when the vox controller came on, it also fed 1.5 volts to the clock, and the clock would run when there was audio coming in. He set the clock for 12:00 and then checked the minutes, and seconds on it when he/we went back to check the recordings in a week. That's how we used to find the best frequency from the 4-5 the coordinator would send us. Just thought I would share, monitoring a channel all day is tough, it needs to be at a fixed location too, preferably where the repeater will be, and on a similar height antenna. If you try to do it manually...well, as soon as you walk away there will be traffic...or could be. So a recording device is very handy.

So I'll throw something out on this topic. I agree the rules say not moving, etc. I have a repeater in my motor home. Its not used while i driving down the road because there is no need, nor do i have an antenna system that can stay up. Once i get to the campground or race track I set up my fiberglass stick, fire up the generator and i am on the air. To me this is a fixed location. Back in my early SAR days we also did a similar setup in our incident command post. While that had a mobile antenna for ease it also was only used once we got to a mission. Both my applications allow a decent install and to date i have had no issues with radios, power supplies or duplex failing me. SAR has since moved our repeater to public safety channels but is still used. So as you said what is the definition of fixed ? A non moving repeater is fixed in my case.

Thank you for that. It is a realistic and practical description of the situation. Also, just for the record, I hunt with a recurve bow.

Sounds like a nice setup, Jeff.

I thought you weren't going to broach these subjects here. Are you sure you want to go there?

To keep things fair, shouldn't you be giving guns and radios to the elk too?

Kenwood TK-8180H in my vehicle and my wife's van for GMRS, Yaesu FTM-400XDR for amatuer use in my vehicle as well.

Your GMRS license is your authorization to own and operate a repeater. Monitoring all 462 and 467 main frequencies for awhile is a good idea to check to see if any channels may be in use for other repeaters.

To clarify, in case anyone missed it: a "fixed station" is a specific type of station that is set up to communicate with another fixed station. The term does not apply to base stations nor repeaters.

Matt, just catching up here... your instal is top notch! Great job!

Ok