Lscott

I saw a mention of a Harris XG-100P. Looks like a nice multi-band HT. Used ones I saw on eBay are going for around $1200 more or less. A bit out of my price range. For info the brochure can be found here. https://www.northeastcommunications.com/harris/downloads/xg-100p-datasheet.pdf

The rules say you’re not to use the repeater main input frequencies, 467.xxx, except to communicate through a repeater. Switching to talk-around mode you’re using the repeater output frequency in simplex mode which is allowed. If you can hear the other station using talk-around you likely shouldn’t be tying up the repeater and move to a strictly simplex only channel freeing up the machine, repeater channel, for someone who really needs it.

I’ve given up on SLA batteries. Switched over to using LFP, lithium iron phosphate, types. A good source is at the link below. https://www.bioennopower.com For solar charging in the field you need LFP specific charge controllers. I have several of the GV-5’s from this company. https://sunforgellc.com/genasun/

That’s what the “talk-around” or “reverse” function is used for on radios. You check to see if you can hear the other station on the repeater input. If you can there isn’t any point in using the repeater since the communications can be conducted using simplex.

I typically carry around a Kenwood TK-3170. It’s certified for Part 90 and 95A. It’s convenient because it’s possible to use the radio down to 440MHz or lower for Ham and GMRS. Between 440MHz and 450MHz covers the repeater section of the Ham 70cm band, only need one radio for both services. For every two way radio I own, used or new, I keep a computer folder of PDF documents for user guides, service manuals, manufacturers brochures and FCC grant (certification) letters that I can find. I also keep the same on my smart phone too. Many of the older Kenwood commercial radios have Part 95 certification. I’ve also have a folder with brochures of various radios that I see mentioned just for reference. When a poster mentions they use a particular make and model radio it’s far easier to just look at the brochure to see what features it has instead of asking a bunch of questions. Most of the commercial radios you can find the brochures without much effort, might have to dig around a bit to find some of them. The brochures many times have the FCC ID for the radio so you can look up the certification info.

I’m going to have to try it out on the XPR-6550’s. I see people claim brand “X” antenna works better than brand “Y” because they can get in to a distance repeater. That’s sort of hard to really qualify without measured data.

Well search for GMRS travel channels too. I happen to use DuckDuckGo as my search engine, and sometimes “Startpage.com”, so if you use something else your results likely will be different. The main point is people just propose something without doing any research first to see if the topic is covered elsewhere. I’ve spent hours looking for info at times going through hundreds of search engines hits. This topic comes up from time to time on this forum with same tired old answers given. What this site needs is a well maintained FAQ section where issues like this are easily accessible to everyone.

Yeah, I read my license and saw the notes about the restriction. However what about all those 2 watt FRS radios, no license required, and almost nobody ever reads the instructions either.

Did you specifically search for GMRS travel channel?

I wish people would do some basic research first about travel tones for open repeaters and the semi official channel 20 for travel. A simple Google search lists a bunch of references on this topic. If people just used what has been the norm for years instead of trying to change it maybe we would have more people using it.

I just got two myself, the dual band GMRS/MURS and the Ham 2M/70cm band, from the Fort Wayne swap last month. I haven't tested them yet using my antenna analyzer. It's on my list when I take time off from work over the holidays.

I've tried testing a handful of HT antennas. They are hard to test. Hold it a bit different and the results change all over the place. Get one that tests crappy then move it around or change the test fixture a bit and bang, it now looks better than the one you thought was the best one in the batch. I've had some that look bad using a ground plane and much better without. Then there are those other ones that do the exact opposite. Go figure. A fair test would duplicate the exact installation conditions in a test fixture as it would see installed on a radio. That's almost impossible to do unless you want to rip out the guts out of a junk radio to add in a cable wired to the socket and run to the analyzer. Then you have to get a calibrated hand and arm to hold it and hope you can replicate the setup from one test to the next. I would like to see how the manufactures do this.

There are several variations of the model. https://qrzcq.com/pub/RADIO_MANUALS/MOTOROLA/MOTOROLA--HT-1000-Specs.pdf

At my Ham radio coffee group meet tonight one of the guys brought in some Motorola radios. He wanted to know if one of the other guys could program them. One was the HT-1000. That was a rather large radio.

I agree. Any test would need to remove as much of the variability due to hardware differences. Some of the Motorola radios have a RSSI indicator feature. I looked at a video where a 7550 was being compared to the 7750e model. Nice feature when you need it. I’m assuming the RSSI reading levels are accurately calibrated. I have both the VHF and UHF models of the XPR-6550’s. I haven’t done anything with them in a while. I have to check and see if they have a displayable RSSI. If they do the second item to consider are they calibrated. Being purchased used I wouldn’t be so sure. Some of the radios didn’t come with antennas so I had to get some aftermarket ones. That’s the other unknown. I had to purchase the antennas since the Kenwood ones won’t work, including the cheap Chinese radio ones. They screw on OK, SMA socket. However the center pin is recessed deeper in the socket on the radio. The pin won’t mate with the center hole on the antenna. The typical reverse SMA antenna the center contact is recessed while the Motorola is flush. They just had to be different, likely done for marketing reasons. Because of this I had to be careful which ones I purchased as generic replacements. Since we’re dealing with FM the important parameter is received signal strength. Radios need a minimum signal strength above the noise floor for an acceptable level of communication quality.

Your points are right on. Even with the often quoted negative 5db, more or less, gain of the typical VHF rubber duck antenna that still leaves a theoretical 4.5db advantage, a factor of 2.82, for VHF over UHF when using an HT with the factory supplied rubber duck antennas. So, a 2 watt MURS radio on VHF could generate a signal strength equal to a 5.6 watt UHF radio, assuming the UHF radio is using a good 1/4 wave antenna on it. In a variable environment like suburban and urban the advantage for VHF over UHF might be hard to qualify even with the gain advantage. In line of sight open areas VHF would likely do better. In an urban area UHF likely would because the signal bounces off buildings better than VHF. This might be an interesting test comparing VHF MURS to FRS/GMRS using the same power and factory supplied antennas in different environments. https://youtu.be/JGSLe39gh8k

Yup, it’s a PIA trying to keep various radio models synchronized. I have a good collection of HT’s just for my own use. I have around 10 to 12 separate radio programming suites installed, mostly Kenwood stuff, with some CCR’s and Motorola in the mix. There are even more than than in folders holding the code plugs since I have both the VHF and UHF versions of a particular Kenwood model series. For examples, TK-270G/370G, TK-2170/3170/3173 are just a few. I have a few of the Motorola XPR-6550’s as well, VHF and UHF models, I got just to experiment with. Unlike the Kenwood’s the code plugs are linked to a radio by serial number. Thus I need separate folders for each radio. For more than a few I can see where one has to use their RM, radio management, database software to keep track of things and make changes. For the few I have the RM is just not worth it to use. Standardizing on a specific model makes sense from code plug maintenance and various accessories point of view.

I don’t know if I would worry about the radio outputting more that 2 watts. Given the gain figure I’ve read about for the typical VHF rubber duck antenna of negative 5db, a factor of 0.32, a 5 watt radio would only be radiating about 1.6 watts anyway. And, of course, using an external high gain VHF vertical the ERP could be even higher.

Those bubble wrap FRS radios many use a stubby antenna that really defeats the gain in performance of a full 1/4 wave if it was used. The difference of a few inches shorter for the stubby I can’t figure out why a manufacturer would do it knowing the performance hit. Maybe they don’t get busted off as easy compared to the longer one. The radio related items I see for sale on eBay in value packs, multiple units, are antennas and belt clips. I guess that’s what careless users bust most often.

I sort of expected the results being a wash between VHF and UHF given how the VHF rubber duck antennas are rather inefficient. The would be in open country without obstructions. In an urban environment there are too many variables that can affect range tests to draw conclusions. As another post mentioned what model radios did you try out?

I mentioned GMRS since you can use external antennas, same as with MURS. Using external antennas mostly eliminates issues with the compromise antennas, rubber duck types, you commonly find used on HT's. The range tests would be more depended on the characteristics of the frequency used than on antenna gain and efficiency. Has nothing to do with what type of communications are being conducted.

Unfortunately you can't conduct business activities on the Ham 2M band. About range comparisons between MURS and FRS radios in the open I don't expect a huge difference between them. However if one is using external antennas that would be different, but FRS that isn't allowed to use external antennas so the tests would be between MURS and GMRS radios. From a very basic technical view point the typical antenna on a GMRS HT is nearly a quarter wave long, about 6 inches, and the body of the radio is large enough to make a fair ground plane. Compared to a VHF radio around 150 MHZ where a quarter wave antenna is 18 inches long so radio body is a poor ground plane. It's often mentioned the typical 6 to 8 inch rubber duck VHF antennas have a negative 5 to 6 db gain relative to a quarter wave ground plane antenna. Without going through the math using quarter wave ground plane antennas for VHF and UHF the VHF radio has approximately a 9.5 db (a factor or 9) advantage due to "path loss" over a UHF radio. So for a 2 watt MURS radio the range would be equivalent to an 18 watt UHF radio with line-of-sight operation. Now using just the rubber duck antennas the over all gain difference is reduced to around 3 db more or less. In practice you might not even notice it. IMHO this is sort of the way I see it.

Other than the few purposed built radios for MURS what other radios have people used for the service? I'm aware they are likely not Part 95 approved but I assume people use them anyway, like older Part 90 radios. Finding good used Part 90 UHF radios seems fairly easy. The VHF models are harder to come by and generally sellers ask significantly more for them.

Well, in a way they already have with FRS and upped the allowed power to 2 watts on most channels. When you start hearing digital communications pop up and no meaning full enforcement then you know it's headed down hill. By my work place I monitor FRS and several local business frequencies on the cheap BTECH tribander in my office. I did catch some brief DMR traffic on channel 17 or 18 a few times. You know it was DMR due to the rapid pulsing of digital noise you hear. I did bring in my D878UV once and decoded it just to verify it was DMR. No FRS radio can do DMR so it had to be either a commercial grade radio or a Ham rig programmed for FRS/GMRS. No idea who or where in the local area it originated from. I'm expecting to hear more DMR stuff and wait to see if the FCC steps in. I haven't heard it in a while so maybe something happened.

The E-Comm mobile truck my Ham buddy worked on was done on a shoestring budget. Lots of volunteer time was invested in building it. I think some, maybe all, of the radio equipment was sourced by the city it was being built for so they had quality radios. Other E-Comm mobiles are built by and funded by local radio clubs. You figure $200 to $300 a pop for a good used commercial grade single band radio, one that hasn’t been beat almost to death, adds up. When you need to cover several bands and services you can easily end up spending $1K to $2K or more just for basic FM radios. Frequently a collection of HT’s, preprogrammed, are kept in the mobile because you can’t depend on volunteers who show up to have their own when the emergency breaks. Then there is the wiring, coax, connectors, antennas, power supplies, battery packs, chargers, lighting etc. so you have to figure in maintenance costs. Radios fail, antennas break, they need repair or spare back units along with the test gear to keep it all running.