Lscott

It's still would be an interesting experiment. Stories surface about counterfeit antennas from at least one well known manufacture are out there. I think it is Nagoya. Antenna testing showed the difference between the real one and the fake. https://www.eham.net/reviews/view-product?id=7741 On another point I have purchased a few "cheap" magnet mount antennas mostly to get the mount from Ham Radio flea market vendors. After testing them the performance was nowhere close to the spec's on the package. Some antenna testing results. http://www.km4fmk.com/AntTesting.html

If the link above doesn't work, you have to copy the whole line and past it into the browser. Then try this one. http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf

You may find this book of interest. The book is about antennas and transmission lines. I hope Firefox didn't mangle this link again. http://www.w3pga.org/Antenna Books/Reflections III.pdf It's a good reference to keep on hand.

You want to really have some fun try testing some HT antennas! They're not easy since the radio, and part of your body, ends up as part of the antenna. When you see the results you'll wonder why they work at all. A few I've tested belong in a landfill somewhere.

I wonder if the guy did the FCC RF safety evaluation. Depending on band, power level and antenna location it's a requirement. Just because its a mobile station the safety issue can't be ignored.

As the license holder of record you're responsible to insure those operating under it follow the rules. Kids have to learn rules for everything as they grow up. GMRS shouldn't be any different. As far as paying a fine the FCC, when they issue one, they don't screw around. Somehow getting one for $7,500 to $10,000 is sort of scary. They want to get your attention and make a point. And yes they most certainly have in other radio services for failure to ID, unlicensed operation, willful interference etc. I don't know about GMRS but it wouldn't be any different. A number of the cases I've seen the FCC contacted the party informing them of the rule violation(s) first. The fine(s) get issued when they party continues to ignore the rules and the FCC notices. Oh, they also have a habit of taking the equipment too in some cases along with issuing the fine(s). I remember years ago asking somebody at the local FCC field office here what they do with all of the confiscated equipment. I was told it goes to a local junk yard straight into the crusher. None of it ever gets sold or returned to the owner.

Thanks. Sometimes the copy and past with Firefox doesn't work so good.

Oops. Linked the wrong version or Part 95 rules.

To be strictly legal the equipment must be Part 95 certified. Older equipment might be listed as Part 95 while newer equipment would be Part 95A. This should be a good reference for Part 95. It covers several of the radio services, specially GMRS, FRS and CB. https://www.govinfo.gov/content/pkg/CFR-2009-title47-vol5/pdf/CFR-2009-title47-vol5-part95.pdf

Alex, unfortunately you're right. 8-( I didn't look carefully at the exact channel layout for both services. The combining of main channels with interstitial ones screwed me up. I found a document on line that shows in a nice graphical format how the two services frequencies relate to each other. Scroll down to last page and it is obvious what is going on. https://apps.fcc.gov/kdb/GetAttachment.html?id=biZxuanIfZOUqdjvLHdsyw%3 D%3D&desc=888861 D01 Part 95 GMRS FRS v01&tracking_number=239603 So as you pointed out the spectrum does look full. What is interesting are the GMRS interstitial channels sandwiched between the main GMRS channels. Its bad enough the low power FRS channels can cause interference on the main GMRS channels now we have the potential of higher power GMRS main channels partially overlapping the Interstitial GMRS channels. Then there is the potential interference of the Interstitial FRS and GMRS channels 8 through 14 with repeater input channels. The requirement that GMRS and FRS must be NB with a max of 0.5 watts is obviously to minimize interference on the GMRS WB repeater inputs frequencies. This is a mess. The interference issues could be mitigated by moving GMRS to NB. That would at least eliminate the multiple channels overlapping due to differences in bandwidth. Since the spectrum is full my idea of of going NB to get extra channels is not going to work in the existing allocated spectrum. Its very unlikely but the FCC could allocate a few new channels specifically for DMR use. As far as allowing DMR within the existing spectrum, well somebody will have to tolerate mix mode operation on one or more channels. Allowing DMR repeaters on several of the channels maybe worth thinking about. You get effectively two voice channels on one frequency pair. There is a lot of experience and knowledge on how to do DMR repeater linking from the Ham bands which could be applied to GMRS.

There would be one benefit to moving to NB operation for GMRS. Additional channels would be available in the same spectrum band. Some claim the service is under utilized now so extra channels wouldn't be needed. However the point to consider are the frequent questions I see posted about running DMR radios in the GMRS service. With newer NB channels the old ones would continue to be analog only while the newer ones would be reserved for DMR operation. This was done basically in the European PMR446 service with Digital PMR446. Originally it was analog only now they allow digital operation. DMR tier 2 uses a NB channel width of 12.5 KHz. https://en.wikipedia.org/wiki/PMR446 https://en.wikipedia.org/wiki/Digital_mobile_radio https://dpmrassociation.org/dPMR-a-brief-overview.html DMR uses TDMA, two time slots, thus two digital voice channels would occupy one NB channel effectively doubling the number of users. The mess with FRS radios can be mitigated with this change also by restricting FRS radios to the currently assigned analog channels. Licensed GMRS users and DMR enabled GMRS radios would have access to both, analog and digital, channels. With some firmware updates existing radios could easily be made available at an affordable price. Some have mention the Anytone analog/DMR radios, D878UV for example, and with a firmware change would likely work just fine. https://www.bridgecomsystems.com/products/anytone-at-d878uv-plus-bluetooth-gps-programming-cable-with-support

I wouldn't say changing from WB to NB is an easy way to get rid of GMRS. The real question is just how many people are running NB now and don't even know it? I see frequent questions about Midland equipment which seems to be NB only. Apparently they sell enough of them. If the FCC switched to NB those users wouldn't notice and most likely wouldn't care since their radios would continue to work reasonably well after the switch. The question of how it would impact repeater owners and users all depends on what equipment they use. If the repeater owner used old Part 90 radios that have both WB and NB capability the switch wouldn't be all that big of a deal. Same for ordinary users. In my particular case most of the HT's I have include both WB and NB functionality. All I need to do is fire up the computer, dig out the programming cables, read the codes plugs, switch bandwidth and then writing them back. Done. A bit of work but not a show stopper. Most of my radios already have dual sets of memories programmed, one for WB and another for NB. Yes it's a pain to flip from one to another depending on bandwidth but I can do it when necessary. Your last point is an excellent one. Sooner or later the FCC is likely to address this with another rule change "tweak". Expecting FRS radios to disappear to solve the problem isn't realistic. There are far too many of them. Perhaps as a group we could start a move towards NB operation for those that have the equipment. After a period of time, with enough GMRS users have switched, any potential forced switch by the FCC won't be so painful. Also a suggestion by others changing the rules to make GMRS the primary service and FRS secondary likely will fail too. People purchased the old combo FRS/GMRS radios, never read the instructions advising the necessity of getting a GMRS license, or just didn't care and used all the channels anyway. Expecting those kinds of people to respect, understand or yield the frequency to the primary user will result in about the same compliance experience, little to none.

A bit off topic. I have a growing collection of hand-held radios, mostly Kenwood VHF and UHF commercial models, and the antennas are getting harder to identify as to band and frequency spilt. Most have no identification on them for the frequencies. The VHF antennas seem to be “fatter” than the UHF ones. However there are different frequency ranges in each band. Seems like Kenwood uses a color coded gasket around the connector to denote the frequency range. I found the site below that has a lot of the antenna models with the band spilt identified by color. http://www.cqcq.ca/viewtopic.php?f=13&t=86

I forgot to point out the currently sold FRS radios are allowed to run up to 2 watts where most GMRS only radios can do 4 to 5 watts. From a practical point of view there will be a small difference between a hand-held FRS radio verses a GMRS radio. Its likely your kids will be using an FRS radio in place of a GMRS radio. FRS radios don't require a license to operate and thus an "easier sell" to the other parents in the area. The main advantage to GMRS radios are a bit more power, detachable antennas and repeater access. I'm not sure it would be a good idea for a group of young kids to tie up a repeater unless it's supervised. Remember repeaters do have a wide coverage area. I don't think people 10 to 15 miles away will want to hear the kids babbling away for hours. The detachable antennas would be nice if you wanted to setup a base station. If you get the Midland GMRS radios they seem to be narrow banded only and thus are compatible with FRS radios.

This is EXACTLY what GMRS is for, family comm's and with other users. I would say go for it. Your point about locking the radios to a specific channel is also an excellent idea. One it keeps the kids from messing up the channel settings and not understand why they can't talk to their friends. They WILL play with the radio buttons. Second as you pointed out it also keeps them from skipping around the channels like an electronic form of hide and seek annoying the crap out of other users. I have a family near by me that does this. I never know what channel they will pop up on and sometimes change while playing radio. Third you do want to make sure they don't end up on a repeater output channel. Young kids will just hit the PTT button and babble away even if the channel is in use. You can't expect kids that young to understand channel sharing. Even a low power FRS radio can wipe out the signal from a repeater if the FRS radio is close enough to another user's radio engaged in a repeater comm. FRS radios unfortunately are allowed on repeater output channels 15 through 22. Forth it keeps the kids from getting "glued" to the computer screen. Finally if the radio gets damaged or lost, young kids have a tendency to do both, it's likely cheaper to replace than a smart phone.

You have some good points marcspaz. About it being market driven, wide band verses narrow band, could get a boost by the manufactures. If they are already narrow band compliant it would be a marketing incentive for them to point it out to customers. Second any wide band equipment only, mostly used, would be eliminated from the market. Now users are pushed into buying more from the narrow band new equipment market and less from now smaller compliant used equipment market. On the regulation front manufactures could point out to the FCC they have good sales of their narrow band radios and few requests for wide band equipment. The FCC could then infer the consumer has a preference for narrow band equipment, or at least don't find it a limiting factor in how they use their radios. Making a decision to go narrow band for GMRS would be an easy one I suspect for the FCC. On the engineering side of things it's rather a screwy situation where you have two different radio services assigned the same spectrum but with different technical specifications for bandwidth. If the goal was really to allow the two to interoperate the FCC screwed it up. Having one station on frequency running wide band and another running narrow band results in some annoying messing around with the volume control. It's either to loud or too soft depending on who is doing the RX'ing and the TX'ing. By the way this happens with DMR when people don't get their audio levels set right. One minute i can hardly hear one station and the other station blows be out of the chair.

I read from time to time proposals to switch GMRS from normal FM to narrow band FM, 2.5KHz deviation, and the arguments for and against it including repeater owners. One of the questions that seems to get little attention is just how prevalent are narrow band FM capable radios out there that are in use? Any legitimate proposal to go narrow band has to address this question. I use several that can do both normal FM and narrow band FM, primarily Kenwoods like the TK-370G, TK-3170, TK-3140 to mention a few. The other point is how many of the current offerings from the likes of Midland, Btech and others that can do both or just narrow band like Midland that gets often mentioned? The point I want to get to is if the majority of radios currently, or at some point in the future, are just narrow band, because that's what people buy whether they know it or not, could be the tipping point where the FCC says GMRS is going narrow band. If most radios at that point are narrow band the disruption for the majority of users would be small so the FCC isn't going to worry so much about the small number of wide band radios out there. The FCC sort of did this with the combo FRS/GMRS radios where almost nobody was getting a license to use the GMRS channels. So they just changed the rules to reflect how the radios were really getting used. They didn't seem to worry much how this impacted GMRS users at the time.

Good luck taking the Tech Class license exam when they start testing again. Welcome to the group. GMRS is a lot of fun.

The rules were changed in 2017 and became effective in 2018 for all of the Part 95 services. All previous combo FRS/GMRS radios are now classified as FRS radios. https://www.govinfo.gov/content/pkg/FR-2017-08-29/pdf/2017-17395.pdf This site has a good summary of the new frequency and power limits. https://en.wikipedia.org/wiki/General_Mobile_Radio_Service The Baofeng UV5R, and variants, don't have the required Part 95 certification from the FCC and thus are technically illegal to use for GMRS. However people use them as such since they're cheap. Is the FCC busting people for using them? Maybe not, but you are playing a game of twisting the dragon's tail so if you get flamed you had fair warning.

I would second that suggestion, Lithium battery. Specifically I would recommend a LiFePO4, LFP, battery. They have the safest chemistry out of the common Lithium battery types, light and reasonably high energy density. One other advantage to LFP batteries is the terminal voltage. At full charge they are around 13.3 or so VDC, a very good match to most mobile equipment that expects 13.8 VDC. The battery has a very flat voltage verses discharge curve so when the terminal voltage drops to 12.8 VDC the battery is almost completely discharged, like around 80 to 90 percent of the rated capacity is used. Don't try this with a lead acid battery. I've also found they have a very low self discharge rate. You can charge them up and let them sit for months and the terminal voltage hardly drops. For an Ecom application this would be an advantage. I've wreck enough Gel-Cell lead-acid batteries over the years I won't buy them anymore if the equipment can use the LFP type. Lead acid batteries don't like sitting around unless they have a trickle charger attached and don't let them sit around at less than full change, they will sulfate the plates. Neither of these conditions hurt LFP batteries. As a matter of fact one recommendation for long term storage of LFP batteries is to discharge them to around 50-80 percent of capacity, they can stay that way for months to a year or more this way without damage. While LFP batteries are much more expensive than the common lead acid type once you ruin a few lead acid batteries you'll get sick of replacing them and the cost adds up. I've had good luck with the following company for LFP batteries. https://www.bioennopower.com/collections/12v-series-lifepo4-batteries If you want to use a solar panel to recharge the battery a small MPPT controller designed specifically for LFP batteries is required. I have several from this company. https://sunforgellc.com/genasun/ I have a couple of the GV5 charge controllers, a good match for a 50 watt solar panel. For solar panels I got some from this company. https://www.renogy.com/products/solar-panels/ I have a couple of their 50 watt mono and 1 of their 30 watt mono panels. The build quality is good and they do guarantee them. On solar panels from my experience don't expect to get more than around 70 to 75 percent of the panel rating, which is derived under lab conditions, which you won't get in the field.

Plugging in the height numbers into this online calculator: http://www.hamuniverse.com/lineofsightcalculator.html shows the difference in range is around 0.5 miles, distance to the horizon, more at the higher elevation. If you were located in an area that was flat its not much of a change. However you're in a bit of a depression so anything you can do to get the antenna higher will be beneficial and a reasonable trade off for a bit more coax loss. At some point you'll likely go for an antenna with some gain which will make up for the extra 1db of coax loss.

I would think very carefully about doing this. Besides going to aluminum to save weight the sheet metal gauge is likely reduced too. With an NMO mount there isn't that much metal area to resist the bending moment of the antenna. I've read more than one account where the roof was damaged, roof area bent or the mount just plain ripped out, when the antenna hit a small tree branch or driving at highway speeds. At least with a magnet mount it will just knock it off the roof most likely with little to no damaged being caused. If you do go with a NMO mount research first for a good way to reinforce the roof are around it before doing the install. Many mobile antennas are fairly stiff and don't give much if they are flexed so an antenna strike goes straight to the mount. Some antennas are available with a spring located at the antenna base. These will reduce the chance your vehicle roof and or antenna will suffer damage from a low tree branch strike or other low obstruction contact.

You want to look at something like the following: https://transition.fcc.gov/bureaus/oet/info/documents/bulletins/oet65/oet65b.pdf https://www.osha.gov/SLTC/radiofrequencyradiation/evaluation.html

That might be a good thing, no fires and little criminal activity. 8-) I hear some interesting stuff every once in a while by monitoring the local mall security frequencies. A lot of them are still on analog narrow band FM with their UHF radios. Some have switched to DMR, P25 or NXDN. It gets better around XMAS. I've heard about hookers by the mall doors drumming up business, chasing shoplifters through the parking lot, fights in the food court you get the idea. A couple of times I heard them kick the local TV news crews off the property if they didn't get prior permission. Once the parking lot patrol spotted a couple doing their thing in a car. The mall security supervisor told the mobile security dude don't bother them.

There are various web sites where you can look up this kind of info. One example is below. https://www.radioreference.com/apps/db/ In the programing mode, I assume one could find the frequencies of government channels like the park service or local police channels. Some may be listen only. Does anyone know how to find out what frequencies are used?