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I’m sure you realize this, but you must have a loading coil to match to a 5/8 wave antenna. Here’s a pretty concise (albeit with some sloppy spelling) article about 5/8 wave antennas: https://www.cainetworks.com/products/antenna/ But here’s an even better article: https://practicalantennas.com/designs/verticals/5eights/

Think in terms of driver and passenger/navigator in off road racing or similar...loud environment, hearing protection, probably helmets. Intercom lets them talk within the vehicle without needing to yell, and also allows interfacing headsets (hearing protective or not, with or without helmet) with the radio to communicate with a base, crew, or chase vehicle.

Use silicone to secure the wires in place inside the radio to prevent rubbing. Seal up the hole at the back of the radio where the wires pass to the exterior. Attach the mini-XLR connector to the wire. White goes to pin 1, yellow goes to pin 2, red goes to pin 3, green goes to pin 4 and black goes to pin 5.

Per the table at https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-90#90.35 NONE of the GMRS frequencies are Part 90 allocations. GMRS main/repeater channels start at 462.550 and end at 462.725 -- the entire GMRS frequency band fits between the Part 90 462.5375 and 462.7375. However, grandfathered GMRS licenses (possessed by businesses) are allowed to be renewed -- but not modified; for the most part such grandfathered licenses are from the days when a GMRS license was good for -- at most -- two frequency pairs (repeater access). Business GMRS licenses probably only specified one frequency. Per Wikipedia https://en.wikipedia.org/wiki/Business_band (emphasis mine)

Hi Mike/WRUZ733, It looks like you're on the right track for configuring the WQPL257: Winchester, Frederick, VA repeater (https://www.mygmrs.com/repeater/4076) ! Great news that the +5MHz is already configured on the repeater channels for the Midland MXT275 radio, it sounds like that part is configured correctly. The next step would be to set what Midland calls the "tC - Transmit Privacy Tone/Code": Setting the transmit tone / code: On page 19 of the manual from the above post there's this item for the repeater channels: "tC - Transmit Privacy Tone/Code - Use this option to set the transmitter privacy code on repeater channels." in that sub-menu selecting "Ct" should enable the CTCSS transmit tones for the repeater (if it was DCS codes the setting would be dC). Updating the "tC - Transmit Privacy Tone/Code" should transmit the code on the repeater input frequency and the repeater would be expected to open the squelch setting on the repeater, resulting in your transmission being heard on the repeater output frequency. As Mike (BoxCar) mentioned, the receive code can be configured to off and that's likely the most desirable setting, especially during initial setup. Setting the receive tone / code: To configure the receive DCS code / receive CTCSS to off: On page 19 of the manual from the above post there's an item for the repeater channels: "rC - Receive Privacy Tone/Code - Use this option to set the receiver privacy code on repeater channels." in that sub-menu selecting "OF" should disable the need to receive a tone on the Midland MXT275 radio, effectively this opens the receive signal on the Midland radio to hear everything on the repeater output frequency. (In the event the repeater does not transmit a CTCSS tone/DCS code or transmits a different tone/code on the output frequency the Midland radio will be able to hear everyone on the output frequency of the repeater by configuring the receive code (rC) to off (OF)). It might take a moment for the repeater to "hear" the tone or code, so try holding down transmit for a second or two (or a "one-thousand-one" count) before speaking. It's possible the settings may need to be updated on the mygmrs page or have been updated on the repeater, and if that's the case it's often a bit of trial and error on the tone or code setting to get things working. You're almost there and are surely likely to have the radio working to full potential soon! Reaching out to the repeater owner via the "request access" button on the mygmrs.com repeater page link might be a good place to ask if the repeater tone / code has changed recently once all the above settings have been tuned. The only settings left to be tuned are the "tC Transmit Privacy Tone/Code" settings and opening the "rC Receive Privacy Tone/Code" settings on the radio. Once that's done you should be on the air! Good luck! -Mark / WRTQ652

I don't know anything about the Midland MXT275. However, I guess it was wrong to assume that radio couldn't do split tones or leave receive off. I still waiting for ICOM, KENWOOD, MOTOROLA AND VERTEX STANDARD to unvail their GMRS Radios. Don't get me wrong, Midland has a great history with two way radios, but I like using Motorolas.

I just ordered the CX-333 to upgrade my Comet GP-3. The GP-3 works well but there is some 1.25m activity in my area plus the CX-333 has better gain. My GMRS radio, the Wouxun KG-UV9GX, is still on backorder. Nearest GMRS repeater is about 4 miles distant. WRUK662 WA7HPK

Hi Mike / WRUZ733, As in Mike's quote, you'll need a tone (CTCSS tone or DCS code) to open the repeater. The reason for the tone is to prevent unwanted noise on frequency from activating the repeater. The tones / codes are listed in the mygmrs.com repeater database (more below). Also be sure you're transmitting into the "repeater input" frequency, more on this after the CTCSS / DCS comment: About the CTCSS tones: If you're using the repeater database here on mygmrs.com ( https://www.mygmrs.com/repeaters) , you'll need to do a conversion between "the number used by Midland" and the actual "CTCSS tone in Hertz". The conversion is found in the Midland owners manual on page 28: Link to Midland Owners Manual search: https://midlandusa.com/pages/owners-manuals direct link (may not work after some time): https://cdn.accentuate.io/81031332017/1623709894082/MXT275-Owners-Manual-11-16-20.pdf?v=0 About the DCS tones: From a radio operator perspective, DCS configuration is similar to CTCSS configuration, select the proper DCS number/setting as listed in the repeater database; select the proper input frequency (or in Midland configuration the proper RPTxx channel) and you should be on the air. In implementation, CTCSS is actually a tone in Hertz, where DCS is a digital ones and zeros string coming out of the transmitter. For the radio operator, each implementation yields similar results, the repeater is able to reject unwanted transmissions (noise) and transmitting with the proper code allows the radio operator to open the repeater to repeat the transmitted input signal of the radio operator. About the input frequency: Also be sure the input frequency is properly set. Nearly all repeaters have an input frequency which is different from the listen frequency. For GMRS +5 MHz higher than the listen frequency would be the standard. In the above manual links, this would be page 27, table "GMRS Repeater Channels". The column labeled "TX Freq. (MHz)" would be the "input frequency" of the repeater. Repeaters are usually listed by which frequency we hear them on, which would be the "output frequency" of the repeater. In the midland example on page 27, a repeater listed as 462.5500Mhz would have an input frequency of 467.5500Mhz and would be on 15RP in the Midland MXT275 radio. (see above links and owners manual for the MXT275, pg 27). Notes from Midland GMRS Repeater Channels table: Ch. Number TX Freq. (MHz) RX Freq. MHz) 15RP 467.5500 462.5500 After configuring the proper CTCSS tone (or DCS code) and transmit input frequency into your radio, you should be able to transmit and receive on the local repeater. Hope that helps, looking forward to hearing your success story when you get your radio working with the local repeater! If you want to talk to other GMRS users and be sure your radio is working, talking on one of the GMRS nets is a good way to find out. Net directory for GMRS: https://www.mygmrs.com/nets *date of post: 2022-10-25 // later readers may see reference links out of date. Enjoy! -Mark / WRTQ652

Try this model file. Five Eights Wave Rev 5.EZ

I just wonder how well it's going to work since the cable/wires are not shielded. The cable/wires go right through in close proximity to the RF power stage. You might have been better off punching a hole in the bottom or side of the face plate and running the cable through there. As a side note I have one of these radios and I'm not impressed with the receiver performance. The radio has poor selectivity in the presence of strong in band signals. A few channels I've had to lockout due to fire paging calls, some from 10+ miles away, showing up on channels I'm sure they really don't operate on. I don't pick these calls up on my other radios. I guess for a $110 CCR ,what I paid, that shouldn't be a big surprise.

60 feet of LMR400 will almost cometely attenuate 5g. (Like 60db)

I bought mine from Harbor Freight for $25 when I was building a custom trans cooler for my GT350. I figured it would be "close enough". I compared it to my friend's thermometer that he used for his restaurant, and it was only 0.5⁰ lower on the reading of the pizza oven. I was happy to see that.

Congratulations you have a 'Rugged Radio' for a total cost of $120 instead of $260.

See that very last line? re-read it. As long as the person using the station(repeater) properly IDs there is no requirement for the repeater to ID. Thank you have a nice day.

It's been discussed way more times then i can count on this site alone and the consensus is that they do not have to ID. If they did have to ID don't you think a crapload of repeater owners would have already been ticketed/fined/ whatever by the FCC for not IDing? And we would have heard about it from them? I think so. Your interpretation of those regs is different than other peoples interpretations of those regs. I trust the explanation/interpretation given by someone else who runs multiple repeaters that are part of this very linked system as it would be in his best interest to have a very good understanding of the issue or not.

It would be just the family under my call sign

Simply put, that can be complied with manually by simply identifying the repeater at the end of a conversation or every fifteen minutes during long conversations.

My great uncle passed away and his family has a Radio Shack 19-1210 MURS Business Band radio pretty much new in box with all the accessories $65.

Not really -- VHF & UHF (and microwaves) are used for satellite control BECAUSE the wavelengths PASS THROUGH the ionosphere with minimal effect. 6m skip is somewhat rare except at solar peak, and 6m is considered in the "VHF 'octave'" (30-300MHz, HF is 3-30MHz, UHF 300-3000MHz). HF frequencies, OTOH, are affected by ionization, and are why many AM broadcast stations have to reduce power or change antenna directionality at sunset/sunrise -- to avoid having nighttime propagation affecting other stations on the same frequency (and the few clear-channel stations that are allowed full power at night now cover multiple states rather than just a few counties). If you are seeing a difference it is more likely due to industrial and business activity generating increased background RF noise which swamps out low powered GMRS signals. Though I will concede I encountered something that I think was a tropospheric ducting event a few months back. https://en.wikipedia.org/wiki/Tropospheric_propagation

Ok, I thought it was saying no tone, From what I have read I do not think I need it to send a call sign if it is private. So that might work.

Do you mean the RT97 won’t do tones for tone squelch, like CTCSS or DCS? It does both. Here’s the manual: https://www.retevis.com/Download/mannual/RT97_English_Manual.pdf The RT97 cannot easily be set up to automatically send a call sign, either in voice or Morse code. The RT97s has a port that might support it though.

The issue with a non-current regulated PWM charge controller is the state of discharge when the sun comes up or the winds begins to blow in the case of a wind system. What happens is the cheap charge controller will apply the float charge voltage value to the battery. Depending on it's state of discharge, that can be a current below or ABOVE the maximum rate of charge for the battery that's connected. Couple ways around this, but it WILL effect the charge rate if you overdo it. If a single 7Ah battery needs 2.5 amps maximum of current being dumped into it, if you put 4 of them in parallel and charge them with a 10 amp source, then they are only getting 2.5 amps PER battery. But that maxes out the source current, and leaves NOTHING for doing anything else like charging phones or other tasks. So you really NEED a good charger to do it right. But there is another issue with charging batteries. And that's just trickle charging them when they are depleted or significantly discharged. Batteries also need a minimum amount of charge current to charge them. Not providing enough current is almost as bad as too much current. And of course, they will not typically recharge completely in the window of time you have the secondary charge source working IE wind or sun. And NEVER leave a battery open circuit for an extended period without charging it. THat will destroy a battery. I have a string of very large and heavy two volt lead acid batteries that this was done to. I am going to TRY to dump current into them and see if I can get them to charge, but I am not hopeful that will happen.

All good questions, all of which I don't know the answers. But as a thought, (please don't burn me for the heresy hahahaha) why not make ALL channels narrowband 12.5, and split all the GMRS into 2 channels each? Should give more channels, potentially allow some sort of trunking?, and as a standard make the upper part of each wideband digital ONLY and the lower part of the old wideband channel ANALOG only. Again, just as a thought. Instead of 22 channels (excluding FRS and including GMRS repeater input) we would have 44 GMRS channels to chose from, so we could run more stuff and double the amount of pairs for repeater usage. But I am aware that it will be a massive change in regulations... so perhaps is not possible to implement. G.