dosw

My magnetic NMO mount came with a rubberized shoe that fits around its base, presumably to not scratch the roof of a vehicle the antenna is attached to. Does this insulation degrade (or completely eliminate) the benefit of a ground plane? With the rubberized shoe over the base, there's no metal-to-paint or metal-to-metal contact with the vehicle's roof.

But the question we're all really wanting answered is what the subject line "Mr" means.

As much as I wouldn't put it past their members to do something like this, and as much as it brings many of us pleasure to see them writhe in discovering flaws in their unsustainable conviction, that specific rumor was a hoax, and was discredited by Snopes. The beauty in the hoax is how believable it is. Watch them explain the ISS, which is always at predictable locations in the sky that are easy to explain if you believe it's in a 254 mile high orbit, and impossible to explain in a way that doesn't have flaws, or require more technology than exists, in an FE model. And the fun thing is that amateur radio hobbiests can contact it, in part, by understanding its predictable orbit, and someone with a run of the mill telescope can see it moving in a trajectory that defies coherent FE explanations.

Let's take that assertion by assertion: "Almost all GMRS radios also support FRS frequencies..." That would be true if you said that GMRS and FRS share the same frequencies entirely, except that FRS radios can't transmit on the repeater input frequencies. All current GMRS handheld radios support all FRS frequencies. FRS and GMRS use all of the same frequencies except for repeaters. GMRS mobile can't transmit on 8-14. "Channels 8-14 on a typical 22 channel consumer radio are reserved exclusively for FRS" That's just incorrect. GMRS handheld radios may transmit on all 22 channels so long as they don't exceed 500mw on 8-14 and stay narrowband on 8-14, or 5w on 1-7. Only handheld GMRS may transmit on 8-14 (and FRS). No mobiles. But GMRS handhelds are fine. Look it up. I did. "These channels can be license-free, ..." No. If you are operating a handheld GMRS radio on any GMRS channel, any of the 22, including 8-14, you are supposed to be licensed. If you are operating an FRS radio on those channels, you don't need a license. "So if yes unlocked the radios will transmit establishing open communications and ensuring the operator has a established license and follows FCC rules. " I can't quite make sense of what you're saying there. But an unlocked amateur radio isn't supposed to be used for GMRS. I'm talking about what is authorized, not what is possible, and not what is enforced. There's really nobody enforcing the use of a handheld ham radio that's been unlocked for GMRS, so long as it's following power limit rules, and not being used to cause a lot of trouble. But according to the rules of the FCCs, you're not supposed to use an unlocked device for GMRS. This is clear in the FCC spec. In practice, those who use any radio for GMRS, stay conformant in terms of bandwidth, power levels, frequency centers, and the stipulation that 8-14 is for handheld, not mobile, nobody really seems to actually care enough to try to enforce whether the radio was unlocked or not.

I find GMRS to really be this, as described above; a tool in support of activities, not the activity itself. I use it for camping, hiking, caravanning, skiing (that's a big one), occasionally at outdoor places like amusement parks, and more recently sailing since ship-to-shore communications are so highly regulated over Marine VHF. I can't help but enjoy it as a hobby in and of itself, but recognize most people just buy a couple (or more) radios and go about using them in their activity.

The radio can be set so that the top row and bottom row are different frequencies, or different memory banks (channels). The radio can be configured to dual-monitor those frequencies or channels. But that's optional. The radio can be configured so that the next time you transmit, it will be on the channel that received traffic most recently. That's also optional, and dependent on dual-monitoring being turned on. The radio can be configured so that it is NOT dual monitoring. In this case, the dual rows just makes it really easy to switch between two channels/frequencies. An example: I could have a radio configured to reach my family on the "A" row, and another family at another campsite, or a hiking group, on the "B" row. I can dual-monitor those two rows, or I can single-monitor but switch quickly using the "A/B" button. With your Baofeng, all of these options are available; dual scan, single scan, transmit on most recently scanned, or transmit only on the row you have manually selected. But the point really is that you can set up "A" for one person or group, and "B" for another, and listen to both.

1) So, transmitting on one simplex channel, and receiving on another. 2x the opportunity for interfering with other users, or being interfered with. I would think that using the standard repeater channels is more reliable. 2) Midland, as an example, has a crossreference guide in its instruction manuals that identifies which tone number matches which actual tone. I have found that the Midland PL tone numbers are at least largely compatible with the PL tone numbers for my old Motorola FRS radio. Other manufacturers may vary, and hopefully would publish their crossreference. And of course some manufacturers don't use numbers, but instead just let you pick from actual tone frequencies. 3) I have an old Motorola FRS that has a scramble mode that is compatible with other Motorolas with the same feature, from the same era. But I don't think that scrambling on FRS or GMRS are allowed under current FCC rules, so there aren't any radios being manufactured today that are FRS or GMRS compliant that offer scrambling. The feature has mostly disappeared. The bandwidth for FRS is something like 12khz, and 20khz for GMRS except for channels 8-14 which remain 12khz. I don't think the old scrambling modes would shift outside of the narrowband range, but one would have to test to be sure. And since it's pretty rare to find an old unit that had that feature, it's rather moot. 4) The FCC seems only to approve a radio for GMRS if it can only transmit on GMRS frequencies. Some can be unlocked, or switched to other modes, though. But the unlocking is mostly an undocumented "feature". Ham radios aren't approved for GMRS, and GMRS radios can only transmit on GMRS. On the other hand, nobody's looking over your shoulder as long as you're observing the rules of the road for the service you're transmitting in. In other words, it's pretty much impossible to know that you're using a UV-5r ham radio to transmit on GMRS, and unless you're creating a scene, nobody's going to care. 5) GMRS radios can receive whatever frequencies the manufacturer wants to allow it to receive. But they must only be configurable for transmission on GMRS frequencies. 6) No way of knowing how many. Probably lots. Get your GMRS license, program whatever radio you want to correctly transmit on GMRS (correct bandwidth, correct center frequency, correct power level, etc.) and use it for that purpose. You'll possibly be in violation but undetectably so. If you're being a good GMRS citizen in every other way, you'll already be a step ahead of the kiddies playing with blister pack GMRS radios.

Is the radio configured to wideband?

Those aren't inherently GMRS radios. The UV-5r has to be "unlocked" to transmit on GMRS frequencies. I imagine the TD-H3 also has to be configured in some way before it will transmit on GMRS frequencies. You bought ham radios for GMRS. They're probably capable, but won't just transmit on GMRS frequencies out of the box without some configuration. Unfortunately the question, as asked, doesn't explain what state you're currently in, other than "it doesn't work." Has the UV-5r been unlocked for GMRS? Has the TD-H3 been configured for GMRS transmission? If you transmit from the UV-5r to the cheapest FRS radio from Walmart, does that radio pick it up? If you transmit from that radio back to the Baofeng, does the Baofeng pick it up? Now try the same with the TD-H3. Because that cheap FRS radio will require no configuration other than to select a channel that corresponds with the frequency you're trying to work, this strategy would remove one half of the complexity from the testing. Amazon has a cheap FRS pair for $16.99. Since FRS uses the same frequencies as GMRS, you're using the simplest device to check the more complex device's configuration. And when you're done testing, you have a couple of extra, super cheap FRS, super simple to use radios to toss into the glovebox and use for close-range communications once in awhile, or to hand out to an unlicensed, non-radio-savvy friend to use.

Might have been relevant information to share initially, that you're trying to work a repeater with an offset of 0.00. That means you're just transmitting on the output frequency, right? Have your friend sit in his car a half mile away, with his radio set to listen to the input frequency (+5.00). Transmit to the repeater. If he doesn't hear you, you're not transmitting on the repeater's input frequency. If he does hear you, you're at least using the right offset. But your post seems to indicate you are not transmitting on the repeater input. Next, if you *are* transmitting on the repeater input, and you're actually getting the squelch tail when you release the PTT, but people at the other end only hear static, and your friend has heard you from a half mile away transmitting on the repeater's input coherently, then you're just out of range.

The PI3B+ uses 2.1A at 5vdc, which is 0.875A at 12vDC. We don't know what the power draw of the BF-888 is at 3.7vDC, but let's take a guess: Let's just guess that passive listening, the 888 consumes 150mA at 3.7v, or .0046A/hour at 12vDC. Let's say it transmits at 5w, so 1.5A/hour of transmission at 12vDC. Now give a duty cycle of 10% for transmitting (which is a lot but not impossible). That's .15A/hr. Add it all up. Consumption is 0.875 + .15 + .0046 = 1.03A/hr. Add some overhead for voltage conversion loss (heat), and for just "my paper napkin math is wrong", and you're at 1.5A/hr. A fire alarm battery is usually 7AH or 9AH. You shouldn't run lead acid batteries below 50%. So a lead acid fire alarm battery would last 2.3 to 3 hours. An RV Group 24 battery is 75AH, and with the same 50% safe working range, would last you 25 hours, or roughly a day. A 100w solar panel will get you anywhere from 15-35 amps per day in recharging. So with a 100w panel and a Group 24 battery you could theoretically go indefinitely, though you would be a lot safer with a 200w panel and a Group 31D battery. Sounds like you might need more than a hobby battery, but we don't really know the duty cycle you're anticipating.

Slightly to the side, or possibly even adjacent to the AM/FM/XM radio antenna, both would probably be fine. But the good news is it's a magnetic mount, so you can experiment and decide what works. If you were drilling holes that would be different. Set up a voice activated voice recorder plugged into the speaker output on a handheld radio upstairs in your home. Put your antenna off center on your roof. Go driving around the city calling into the channel you have set saying "Radio test from (xyz location) bearing west, this is WRQW999, no response required." Then turn around and do the same, from the same location, facing east, north, south. Now go to another location and do the same. When you get home, listen to your recordings and decide if being three inches off-center has mattered.

If you have a UV-5G you should probably be using it in memory mode, not VFO mode, to talk to other GMRS and FRS users. VFO mode serves more advanced needs, like allowing you to listen to any frequency within the devices range, and to go directly to a frequency, without the convenience of memory slots. You can still only transmit on the GMRS frequencies, which are pre-programmed into the memory slots in memory mode. Later you may set up a PL or DCS tone for a GMRS channel to have quieter communications between you and the other radio. And at some point you may find a repeater to use, get permission to use it, and then set up your equipment to efficiently access that repeater by programming a memory slot for it. You can do that painfully through the keypad, or more easily with Chirp software, though even that requires a little technical understanding to get it running and to use it correctly.

Obviously you're already aware of this, but for those who aren't: Wide open deserts aren't conducive to 50-60 mile range from a handheld, because the curvature of the earth puts you out of line of sight. Handheld to handheld over perfectly level ground, each antenna at 5 feet height will yield about 6+ miles before the curvature of the earth blocks the signal. Pretty good range can be achieved over a desert if two parties are on plateaus over a desert valley, though. In that case, 50-60 isn't impossible. (update): And reading a little further in the thread I see you mentioned curvature of the earth, too. I wonder how the flat earth crowd explain the RF horizon.

https://mygmrs.com/repeater/6370

So you have the radio in VFO mode, and while scanning through frequencies near the GMRS channels, you overheard talk on 462.6200, which is 5khz below 462.6250, GMRS channel 18. The bandwidth at GMRS channel 18 is 20khz. So by being 5khz below the center, you would still be able to hear channel 18, just at a lower quality than if you were actually listening on 462.6250. 462.6250 with 20khz bandwidth spans 462.6150 to 462.6350. The freqency 462.6200 is within the +/-10khz bandwidth (20khz bandwidth overall) of 462.6250. Imagine the old days when you would tune your FM radio with an analog knob, and see the station you're on using an analog indicator sliding along a transparent rule with markings on it. You basically turned the knob just slightly to the left. You still hear the transmission, it just doesn't sound as good because you're clipping off the higher frequency end of the transmission's bandwidth.

Tone has nothing to do with it. If you are picking up on 462.620 you are possibly just tuned off-center for channel 18, 462.6250. If you configured your radio to 462.6250 you would probably hear a better quality version of the same transmission. What GMRS radio are you using?

462.620 is 5khz below GMRS channel 18 / 462.6250. Given that GMRS channels are spaced 25khz apart, with 20khz bandwidth, someone transmitting on 462.620 would fall within the bandwidth range of 462.6250 (which would be 462.6150 to 462.6350: 462.6250+/-10khz). It doesn't make sense that there would be an FCC approved device legally transmitting within the bandwidth of a GMRS channel which is approved for 20khz bandwidth.

Agreed. I think the OP must be thinking that the convenience of a handheld unit around the house, not be tied to the base station is the motivation. Otherwise I'm at a loss for why he asked if he should put up a repeater, everyone essentially said nah that's not going to help you. And he followed up by saying he's going to do it anyway. It's a little baffling why the question was asked in the first place if the decision to put one up was a foregone conclusion. ...so my take is there's something we're not being told, such as, not wanting to have to sit around the base station all day, but rather, use the repeater with a good antenna to allow for more mobility around the house by providing a link for a handheld.

Put up a base station. Put up an awesome antenna. Attach a VOX digital recorder to it. Go driving around in your vehicle, checking in with your base station from various locations. Review the recording. If you find that some of your checkins weren't captured, or were too difficult to hear, you will have saved yourself hundreds of dollars by identifying that a repeater wouldn't be any help in your situation. If all of the transmissions did make it through, then you may be on the right track.and you can repurpose your base station and antenna hardware as parts of the repeater system you build.

The Amazon listing for this item states: "Supports CHIRP programming (select "UV-5G Plus" under Radioddity.)" That aligns with how you would also select the UV-5G (not Plus); it is listed in CHIRP under Radioddity instead of Baofeng.

Here's what would need to happen. It's likely that if one had access to Midland's MXT-575 firmware source code (which is probably a proprietary, copyrighted trade secret), they would probably determine that the "channel" frequency configuration is hard coded into the firmware, while other variables such as PL tones are configurable through the keypad. And the firmware does not provide a protocol for altering configuration by way of programming cable. There is probably a bootstrapping system available for Midland to tie into for firmware updates, but that system would be for the purpose of overwriting the entire firmware. If you look at other embedded systems such as home routers, you'll see that there is an open source software project called OpenWRT that allows enthusiasts with sufficient technical understanding to load OpenWRT firmware onto their router (as long as they own a supported router). This OpenWRT firmware is designed to provide configurability in areas that stock firmwares from manufacturers of routers don't typically provide. OpenWRT sprang into existence for *routers* because routers are a large market, they typically, internally, run a tiny version of Linux, and have a lot of potential for firmware improving their configurability. In this case, what you're desiring would probably require a custom GMRS radio firmware first, that exposed capabilities not built into the stock firmware. Such a firmware could provide programming capabilities via USB cable. The problem is that this doesn't exist. Midland GMRS mobile radios are too small a market to spawn a group of enthusiasts to develop their own firmware, engineered to leverage Midland's boot loader and to fit within the hardware constraints of Midland GMRS radios. In the case of routers, it's a huge market; every home has one or more router. But GMRS, overall, is a smaller niche market, and there are options from other manufacturers that allow for programming without going to all the trouble of creating custom firmware for a Midland radio. So this side-loadable firmware just doesn't exist. Enthusiasts of GMRS don't go to the trouble of building custom firmwares to side-load into their GMRS radios. They buy radios that have the capabilities they need, and get a CHIRP profile added for that radio. The MXT-575 is a very useful radio, easy to use, nice quality, nice design. But for a radio that provides programmability via USB cable, and that provides 999 memory banks, a KG1000G-Plus is $389, and an MXT-575, in good condition, should fetch at least 250 on eBay, freeing up a little cash to use to obtain a model that is better for your needs. (When I say "that doesn't exist", I've looked; I checked Github, where many open source projects store their code, I've searched using search terms that would be common in such projects, I've looked in PyPI, CPAN, Node repositories, Java repositories, C++ repositories... I'm a software developer, and while there are millions of places to look, I've covered the ones that would usually matter.)

What's funny about this is they advertise "3-mile" range. I assume it's 500mw. But it seems like that was the state of marketing in the 90s before companies started claiming 16 miles, 18 miles, 22 miles, 38 miles, on radios that were inferior in terms of their antenna, and equal or only slightly better in terms of transmit power. Three miles was a real-world "out in the open" estimate, and is a LOT more accurate than blister pack radios nowadays claiming 22 miles of range.

Welcome to the Internet, where the strongest opinions are the ones who prefer to shoot down the question rather than leaving room for it to be answered by those who may have ventured beyond the immediate obstacle. I do have one observation, though. The MXT-575 has a total of 23 "channels", where a channel is a frequency (simplex) or a frequency pair (repeater). You get one configuration per channel. Configuration on all simplex channels consists of PL/DCS tone or code, power level (which is limited to Low for channels 1-7), and channel bandwidth (narrow band - default, or wideband). On the repeater channels, you add both Tx and Rx tones or codes to the configuration. The 23 channels are directly tied to immutable frequencies; 1-7 and 15-22 for simplex, and 15r-22r for repeater frequency pairs. Channels don't get to be named. What I'm suggesting is that the configuration is very simple, to the point that you wouldn't have as much need for CHIRP or other software support. Radios that benefit more from supporting uploads from a computer generally have 100+ "channels", but in their case, the channels have configurable frequencies within the range of GMRS frequencies. So if you take a Baofeng UV5G radio as an example; each of the 100 channels can be set to any frequency within the radio's range. You may have all 100 channels on the came frequency if you want, each with different permutations on tone/code, power, and memory bank name. The point being, many radios equate channels to memory slots. And the memory slot can contain name, frequency, power level, bandwidth, tx tone/code, rx tone/code, and possibly squelch. And there will be 100-999 memory slots. Compare that to an MXT-575; it has 23 memory slots, and the slots do not allow you to set the frequency or a name. That means you get only ONE repeater on "channel 15", or on a particular frequency. One could argue that this reduces the need for programming capabilities, though I can see the opposing argument that if I'm heading across the country and want to use repeaters local to the map I'm travelling within, programability would be very useful, to avoid having to change "channel 15r" again and again manually to the repeater tones in use in that area for that frequency.

Hood lip mount with two antennas that you change out depending on the use-case. Day in and day out, use something like the MXTA25 ghost antenna. It's not awesome, but it will never get hung up on your garage door. And then when you head out for a few days (garage is now not an issue), swap over to the MXTA26. They're easy to swap. Another alternative is to go for a half-wave antenna on an NMO mount. Get the hood lip mount for it. The half-wave is going to be shorter than the MXTA26. And a half-wave antenna doesn't need a ground plane. Select one that is marketed as not needing a ground plane.