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From my reading, the MXT275 is set to NFM. Can this be changed? Sounding like, no. I don't feel like I need a 40W (MXT400) or 50W (GMRS-50x1). I like the compact and versatile package of the MXT275. Just got it a last week. But so far it's in the house with a UT72 mag mount on my metal framed desk on teh second floor. Hitting my local mwGMRS net repeater about 40 miles away, nice and strong. Can't wait to test it out in the car. Waiting for the NMO Mag mount with UT75 NMO. 72

If GMRS ever allows DMR I would think SFR mode would be the way to go since it would be simple for a user to setup, no fancy controller or cavity filters to deal with. In fact this would be ideal for a Ham buddy that's into off-roading with his Jeep and the group he belongs to. They are switching to GMRS since that seems to be the direction the off-roading community is moving towards. He's trying to get the group members to get their Ham Tech class tickets. If he can do that then using DMR with one radio setup as the repeater using SFR mode would fit exactly what they are looking for without a complex system to drag around. If a particular frequency is busy you just switch to another one. Can't do that in the field with a conventional setup.

I can vouch for the Ebay Cable guy it's BlueMax49ers I bough all my programming cables (iCOM, Kenwood, Motorola) from him (Mark KJ6ZWL) all his cable are FTDi Chip fast shipping too. My latest purchased from him was the programming cable for XPR8300 and as what gman1971 say all cable works just fine.

I have my Midland MXT400 set to use the 20kHz bandwidth on the channels on which it is allowed by Part 95E. I also have the local repeaters programmed into the slots meant for the channels reserved for the FRS handhelds. The software and cable (DBR1) is available. Cable - https://midlandusa.com/product/dbr1-dual-band-radio-programming-cable/ Software - https://www.dropbox.com/s/eibap1ve5nnl5ju/MXT400_Setup_1.05.exe?dl=0

He is saying you can set the bandwidth to the legal Part 95 20kHz from the 12.5 that Midland ships the rig set to using the software.

Marc. Could you point to those posts. Specifically, did the FCC find the site to be in compliance, or the radio? Also, I would not take "not finding any issues" to be synonymous with "in compliance."

All I can add to this is that I bought the Midland 400 not knowing much accept is was FCC type certified. Like a lot of new users we buy a unit and then start to research more about the usage. This case being GMRS. I really bought the unit to put in my Jeep for trail communications not wanting to buy into a dead horse IE CB. I have a brother who has been into HAM since the 70's and so I understood in a basic way of repeaters and such. GMRS has so much more to offer than just a trail radio and I wanted to use it to its fullest extent. That is how I found its shortcomings in the areas of using it with repeaters. I overheard a discussion on the radio one night ( on a repeater channel) of how someone got software and instructions from a Midland engineer and how he was going to post a video on how to do it along with a link for the programming software on the Midwest GMRS forum. I had found snippets of this before of this but no definitive "how to". Anyway I'm getting off point here. I watched that video and downloaded the software. I bought the programming cable from Midland. The original video was taken down because it had repeater codes showing in the video. he redid the video without the codes showing. In the video he showed how the change the bandwidth from 12.5K to 25K. When he had the software read and download its current settings , the repeater channels as well as all the other channels were set to 12.5K. When I read and downloaded my radios settings I was surprised to see the repeater channel band width already set to 25K. This is how it came from the factory. I ordered that radio on August 10th. I didn't do anything to this radio up to then except turn on the repeater channel function and load tones for use from the front panel of the radio. Yes from the front panel of the radio you can only load one tone for both the input and output of said repeater channel. That tone had to be the same for input and output so that limited me to only repeaters using the same tone in and out. In the end I now have a radio that functions within the limits set for GMRS radios. I fail to see how using the software to use split tones or change the bandwidth ( which I didn't as it came from the factory that way) would make this radio illegal. It may invalidate the FCC type certification but I really doubt it. I would think type certification is really just a bonus for the manufacturer in terms of marketing. How many of you in this discussion are using radios not certified but within the rules? It sounds to me like most of you are using commercial radios programmed to within the GMRS parameters. Are they type certified?

Except Part90 ≠ Part95. You have taken Part90 rules (47 CFR Chapter I - FEDERAL COMMUNICATIONS COMMISSION; Subchapter D - SAFETY AND SPECIAL RADIO SERVICES; PART 90 - PRIVATE LAND MOBILE RADIO SERVICES (§§ 90.1 - 90.1338)) and seek to apply them to Part95. While Parts 90 & 95 are both contained in Subchapter D, they are separate, independent and unrelated.

I would argue that is the 100% the manufacturer’s responsibility, in this world of software defined radios and certifications, to ensure that the firmware of the radio is written in such way as to ensure the radio remains in compliance with the FCC requirements. The firmware of the radio is not intended for user modification in anyway. The firmware is how the manufacturer’s leverage the exact same electronics to build radios to serve different markets, achieve different certifications, and expose different feature sets that yield different prices from the public. It is the specific combination of hardware and firmware that defines the radio. If the firmware of the radio allows the radio to do something that is disallowed or otherwise outside the specifications of the FCC, then the manufacturer has failed their responsibility. In contrast, again in this modern world of software defined radios, it is common place, and even expected practice, that radios be programmed by the user; the public. Programming is made possible through modifications of exposed settings available to the user via front panel controls and, if an externally accessible programming port is available, by means of external software. It is reasonable to conclude that, if the manufacturer has done their job, any and all settings that can be changed on the radio are a candidate for modification without affecting its legal usage. While we call changing the settings of a radio “programming”, actually we are doing nothing of a sort. We are not adding logic, business rules or enforcing and legal limits, we are merely changing the settings exposed to us by the radio’s design/implementation. I currently write software for a living. Any setting I expose to the user is fair game for modification. Any value the user provides is validated to ensure it is within an allowable range (where necessary). Where critical combinations of values are material, said combinations of values are validated to ensure they collectively pass muster. In an SDR, such ultimate rules are the responsibility of the hardware-firmware..the part of the radio not intended for user modification. I own a couple of modern HT, both of which are programmable via front panel controls and via software to various degree. When I make the mistake of setting values outside the allowable limits of the radio, the radio itself prevents the value from being used. If I am using the manufacturer’s software, the manufacturer’s software will tell me so and disallows the sending of the invalid value to the radio. Chirp on the other hand will not warn me, but will let me send the invalid value. However, if/when I attempt to use the radio with that setting, the radio itself warns me with an audio/visual indication of an invalid value and will not operate. Case in point... an invalid Tx frequency. In this case, the manufacturer has done their job. So to wrap this up. If the manufacturer of a GMRS certified radio has done their job per the intent of the FCC, the radio will not operate using any setting that would cause it to perform outside legal limits. The public has an equal responsibility to adhere to rules as well. If the user knowingly exploits a manufacture defect and use settings outside FCC limits, they are knowing breaking the law. If the midland radios make available settings to change by means of their programming port, it is reasonable to conclude they are, by design, intended for modification. Conversely, if you knowing exploit a manufacturer deficiency and set values outside the FCC limit then you have crossed the line. Michael WHRS965 KE8PLM Sent from my iPad using Tapatalk

I have to go with @hans' well prepared and documented presentation on this issue. Further, I would like to add a point that, I believe, has been missed so far. In §95.337 there is a primary condition placed on the limitation of modifications: No person shall modify any Personal Radio Service transmitter in a way that ... ...operation of the modified transmitter results in a violation of the rules in this part. In this case, the term this part refers to Part95, Personal Radio Services. So, as long as a GMRS certified radio continues to transmit within the rules set forth in Subpart E - General Mobile Radio Service (§§ 95.1701 - 95.1793-95.1899), modifications would be permitted. Now, there is a separate limitation in that same paragraph that prohibits modification of the ...form of modulation. So, we need to know what the FCC means here by the term modulation. And we find that answer in: 47 CFR §95.303 Modulation. A process of altering the amplitude, frequency and/or phase of a radio frequency carrier wave generated within a Personal Radio Service transmitter, for the purpose of impressing onto the carrier wave information to be transmitted. This is distinctly different from the term Emissions Designator, which describes Bandwidth, Modulation Type, Modulation Nature, and Information Type. So, as long as the radio continues to transmit in compliance with §95.1775 GMRS modulation requirements, which authorize both narrow and wide band operation, changes in bandwidth alone would be acceptable. And, finally, all else aside, if a radio is modified by programming solely to alter the received PL, etc. settings, such modifications would not affect the transmitter and would be completely permissible. So, in conclusion, based on @hans' posts and the information included here, I now have to say I believe @marcspaz's original contention that modification to transmit bandwidth, and in fact any modification at all, was incorrect. I contend that any modifications that do not cause a certified GMRS transmitter to operate outside the rules stated in Part 95E, are allowed.