PACNWComms

Talk In versus Talk Out range, something that does need to be emphasized at times. Kudos to those that did in this forum. I use a 25 Watt Spectra briefcase repeater when I head into parts unknown. With an antenna on a tripod about 30 feet above ground level usually gets me a few miles increased range, if on a hill, often ten or more. This works for my use case, as all other users are carrying four to five watt handhelds. Great portable repeaters, but getting harder to find. I use two deep cycle marine Optima batteries and often get an entire weeks of use before a charge.

Your method can work, but I would recommend fuses in both positive and negative wires, and also some method for charging that battery. Many radios do draw a small amount of current when turned off(and will lose some charge sitting as well), and your battery may be dead when needed if there is no charging circuit, or method to trickle charge the battery. If you wish to use a car type battery for backup, add a Battery Tender or similar type of charger connected to the posts, to keep the battery charged. The, it is as easy as you mention. Uninterruptible Power Supplies (UPS) units also work well for this purpose. At work today, I just repurposed several Eaton battery backup power supplies for exactly this use case. I have some mobile radios that are lightly used, but when the are needed, they need to work. Seeing many UPS units that just needed new batteries,I swapped in new gel cells and charged them up for their new job, as backup power for these radios. For my use, I only need the radio to work for an hour or so when AC power is lost, so small desktop, or under the desk UPS units work for me. If you need more time, use a larger UPS.

From my own experience in the oil and gas industry, many radio systems for refineries, transfer stations, and related areas are either full on P25 Motorola FDMA (and/or TDMA P25 Phase 2 now), or large scale Linked Capacity Plus Trbo systems. Even here in the Pacific Northwest, I know of no GMRS repeaters in use by the oil industry, they use an event channel on their main radio system. Some even have their own parks and recreation areas, also often used for training and family events, with those events using a specific channel for radio comms if/when needed. Repeater range costs money, and yet there is always the issue with intrinsic safety standards, so a radio network will only be as big as it needs to be. Oil and gas work is dangerous, and even the tablet computers and other electronic tools, flashlights, gas monitors, all have to be built to an intrinsically safe standard. That drives a huge part of the radio footprint in the oil and gas industry. As for 102" whip for GMRS, it all has to do with resonance, and that length is for old school CB in 27MHz. UHF GMRS will benefit with an antenna that is resonant between 462-467 MHz.

Performance is the same, the cure time just determines how much time you have to work the pieces together or support it until dry. I use more of the fast cure, as I am often using smaller parts (marine VHF antenna mounts and connectors), where the regular is probably what boat builders use, as they may need to move things a bit to fit pieces together and may need some wiggle room. Since my last post, I have also been shown how this is used in recreation vehicles as well, especially around the TV (over the air digital) antenna, air conditioner, and other penetrations in the roof of that type of vehicle. Buy it at a hardware store (not a boat or RV store) to save some money.

Yes, at those prices, they are a great deal. I should have added to my XPR7550e purchase at $505, that was to prove a point to my employers procurement process, they pay Motorola $1172.00 for each XPR7550e. Usually, I look for the better deals, but in this case, I was making a point to them that the price is less than half if I pay with a credit card instead of a purchase order. I still can't believe I paid that myself looking back.....I could have bought a lot of other radio gear at that price, and my XPR6550 still works and looks practically new, even after some drops on concrete. (But the so does my Anytone 878.) 6580's for $85, I need to get to my local ham swap meet sometime, has been a few years and that is a great deal.

In the military I went from Motorola for commercial radios, then worked as an engineer in the JVC/Kenwood Group. I stay away from anything made when too many former Microsoft software engineers were hired.....2012-2017 or so. Now, I am back to Motorola. My XPR7550e was $505 to y door from Sunny Communications. XPR7580e's are $385 plus tax/shipping, also great radios. I also use XPR6550's and XPR6580's, I totally agree those are great for amateur use, and even cheaper now that the are "end of support" by the big M. Since batteries are readily available, I have recommended the 6550 for many GMRS users, as a solid radio, if you do not mess with programming all the time, or travel the country and need to make changes (I do not assume everyone has CPS and cables, even though those are getting cheaper too.) As for Ukraine, it did not surprise me much to see DMR in use, I had to buy a pile of XiR8668 (Asian market XPR7550) for a project a few years ago. With the new R7, Motorola is keeping the name the same worldwide, no DP4x00 for eastern Europe, XiR86xx for Asia, and XPR75xx for the Americas, all being the same hardware.

On the Ukrainian side, looks like Motorola DMR. Very capable radios. I myself use a Motorola XPR7550e for GMRS and other UHF personal comms. https://k0lwc.com/what-radios-are-ukrainian-military-using/

No matter which antenna you end up using, I would highly recommend 3M 5200 sealant for use on the coax penetration. Years of adding radio antennas and satcom equipment to RV's for emergency communications has shown that sealant to work very well for keeping the water out. It is also used by Bayliner/Sea Ray/Meridian for their vessel hull penetrations. As others have mentioned the Air conditioning unit would be a good place to mount to the metal under the plastic cover, perhaps even having the antenna poke out through one of the vent holes in the plastic. You would also have the opening to the inside for the coax run. Just use a lot of good quality sealant on that roof. Although, I live in the Pacific Northwest, and everything gets wet, eventually, you may have a different climate or use case for that camper. Good luck.

That's the truth, just licensed two commercial sites in Florida and one in Colorado, thousands of dollars for UHF spectrum. Luckily no towers, repeaters, combiners, or duplexers needed, just spectrum for line-of-site comms. However, the Colorado site was using Midland T70 radios and wondering why they were not working well. Half million square foot warehouse and acreage around the facility. Some were in low power mode, others high power. Sent them some trusty old but great condition Motorola EX500's at higher power. Just needed licensed freq's for commercial use.

Good to know, and like many other radios, even much more expensive ones out there (Motorola, Thales, Harris have also had issues with this over the years.) Thank you for sharing for all of us.

I had this issue with my GM-30 handheld when I got it as well. However, I had bought the GM-30 handheld/DB-20G mobile combo online. My original intent was to use the DB-20G for home use (even though I had a Motorola CDM1550LS+ in use as well, I like the smaller size and easier programming), and the GM-30 for my smaller daily commute car. Well that USB cable fell out often. I then realized the DB-20G fit perfectly in a "pocket" in the console made for an iPhone. On a slightly different note, I had a friend that bought the GM-30 handheld, and spent about a week charging it with the USB cable, and complained that he could not program it properly. I found out he was trying to program it via USB as well. He also wondered why it came with two "programming" cables. His laptop also never found the "drivers" for that USB C cable either. He is on the right track now.

I can credit Notarubicon for getting me into GMRS once again, after years in commercial and amateur radio. It was one of his videos on the new license process, and a Midland mobile. $70 dollars to the FCC via credit card, a couple of days later, I received the email with the new license. Then it was a couple of days and registering on this site,and confirmation maybe a day or two later. I recall some FCC database issue going on at the time, so it took an extra day somewhere in there to confirm call sign and become a member of this site.

These threads always show me why keeping my portable repeater private is so important. There is always an assumption that other peoples hardware is fair game, just because it is operating in "public" spectrum. Either there are many people that have never been "burned".....or society has become so used to certain things being public domain. While this site is a great resource for those getting into the use of GMRS radios, it will always be impacted/limited by certain expectations. With known spectrum, as well as tones, anyone with a little bit of knowledge can impact any repeater that they find. Take linked repeaters into consideration, you may have a user several states away. Then you have someone abusing the repeater, swearing, talking about business, or kerchunking all the time. How do you track down the problem? Or do you just shut off the repeater in the hopes the person ceases their action? There are many reasons to require phone numbers, call signs, shutting off Talk Permit tones, even signed agreements to access equipment. A call sign was needed to access this site. This website is owned and operated by someone else. You may find many more repeaters in your area in use if you scan for them, many that may not be listed on this site, as they wish to remain private, or for specific users. In my case, I have yet to find one that wanted a phone number, but many that wanted an email sent to them, with a Call Sign,. which can allow a repeater administrator to find that phone number, address, and other information if needed. Put one up yourself, and you will find out why some may want or need that number. Good luck on GMRS.

Need to come up with some sort of FCC betting chart on when they will actually enact the new fees. This is true at every level of government, always tending toward charging the citizenry. Time will tell when this happens. GMRS wise, I am good for another 9.5 years, amateur wise - to years left. So, it will be the amateur license that will be my litmus test, see if I end up paying for my re-newal.

I see this often, and the backup is usually something very low tech, such as a map, compass and protractor for location, and a cheap analog radio for RF comms. At work, I am going through this with some sites that think they need multi-band Motorola radios (APX8000) handhelds, which is hard to "sell" to those controlling the money when only a few people really need that capability, and get along with an 800 MHz radio on their hip and the other band in mobile radios in vehicles/office areas. The only "do everything" type of radios I have used were Harris AN/PRC-152/117 mobile/backpack series radios, and the backup to them was another of the same radio. Luckily, GMRS is a lot cheaper with many more options.

To add in for the dual serial numbers you noted, those are for different boards inside the radio for NXDN and P25. Different manufacturers made each board, then they get placed Lego style inside the chassis as ordered. You wait too many software revisions later to upgrade licensing to actually use that P25 board, and the radio needs to be sent to Kenwood for a new P25 board with newer firmware that will actually take the Kenwood generated license to activate that function at that time, then find out you are out that money if the radio does not work in P25 as needed, when needed. The idea was to be eligible for federal grant money for P25 capable radios for public safety, with the intent to be like Motorola and their Entitlement ID's for CPS, or unlocking features within the individual radio.

From my time as an engineer with in the then JVC/Kenwood Group, the idea was that Kenwood radios could be software/firmware upgraded at a later date to P25 specification if needed, as the hardware already met spec in order to get grant money for public safety entities. Kenwood could beat the competition on price, and smaller municipalities had a radio that could in theory be upgraded to P25 capability for actual use, but still had enough hardware compatibility for those grants. You could save thousands per unit, and still con the government into receiving grants. The problem with this, is too many Microsoft software engineers that lacked radio knowledge and experience. It was common for a radio that later needed to actually work in P25 spec, to need to be sent to Kenwood for hardware/firmware/software upgrade to actually work in P25 mode. Also why there are so many 5000 series radio models as they broke model out by what was actually shipped. Sort of like having another car model for each option package you bought. Kenwood lost a lot of "street cred" with these situations. Including me, seeing it within the Group. Some situations also involved running out the warranty clock on fixing those problems. This happened with: Viking, EFJohnson, Kenwood, Zetron, and JVC video divisions.

I totally agree. The first step should have been a Rino compatible device, then branch out if it proves popular. MURS was probably offered for long range and no license required, and that was the end of discussion in some corporate meeting. I would buy one in UHF band for sure. I need that for my part of the country. In hind sight, I should have bought stock in Garmin, with all the money I have spent on their products over the years.

Was waiting to see this comparison at some point. Thank you for posting. That bigger display also means less likely for my employer to purchase these for "fire" personnel. The biggest deal breaker though is the Motorola Trbo Ion series accessories that the R7 uses.