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ljh505

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    Albuquerque

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  1. The waiver note is bogus. Mention of a waiver is an error in the FCC renewal system for GMRS licenses, because waivers are summarily denied. Did the waiver 3 or 4 months after my GMRS license expired. Spent over $200, and the petition was denied. At the end of the denial explanation, the FCC told me to just buy a new license. This should be what is displayed for an expired FCC GMRS license, not "you can submit a waiver". So over $270 later, I had a new GMRS license and callsign. Don't do the waiver process. Complete waste of money... just apply for and get a new license/callsign.
  2. I have a Midland MXT275 MicroMobile for the truck and some Midland GXT1000 series handhelds which get the most family use in simplex mode when camping or hiking. I also have an older Wouxun/Powerwerx GU-16 GMRS handheld (product is now discontinued) which can work repeaters, but I use that mostly on the southwest regional linked repeater system from the living room at the house here. The Wouxun is a pain to operate in the field, as it is a Part90/Part95 16-channel radio which needs to be programmed with a USB cable hooked up to a PC like most Part90 radios, rather than from a menu on the radio itself. I do not have experience with the newer Wouxun or BTech radios; there have likely been many improvements in user interface over the last 8 to 10 years.
  3. Ok, that confirms my suspicions. My guess is the MXTA26 is pre-tuned to work on the MXTA12 Midland mag mount with a center-of-roof placement. Once you deviate from that configuration, there's not enough whip length to cut-to-tune to other configurations.
  4. You've gotten two posters confused here. The fellow with the "burnt paint", user @H8SVMT (https://forums.mygmrs.com/user/3591-h8spvmt/) had the antenna mounted on a mag mount on the painted part of his vehicle. Since discovering his paint was blemished by a RF burn, he has since moved the antenna to a separate metal bracket to avoid further marring of the paint. I'm the OP, and I have the antenna mounted on a Diamond K400 trunk lip mount per the original post and photo. I agree the K400 and its "set screw" attachment to the trunk lip could be suspect, but given that a commercial land mobile UHF antenna of similar design (a Browning BR-173-S) tunes up just fine to a 1.2:1 SWR on the same mount per this post: https://forums.mygmrs.com/topic/2212-browning-br-173-s-antenna-on-a-small-car/ the issue is with the MXTA26 antenna, not the K400 mount. The tuning plots provided in the original post and in the BR-173-S separate review post are from a RigExpert AA-650 Zoom, which is a fairly new antenna analyzer with UHF capability.
  5. Just out of curiosity, what NMO mount are you using, a mag mount from Midland, a 3rd party mag mount, a 3/4 inch traditional NMO hole mount in the roof, etc.?
  6. I think the treaty with Mexico for coordinated land-mobile UHF comms is for 470-512 MHz; link to current treaty dating to the mid-1990s from the FCC page is given below. https://transition.fcc.gov/ib/sand/agree/files/mex-nb/470-512.pdf The treaty region extends 150 km on either side of the border. The GMRS repeater pairs are 462 MHz outputs and 467 MHz inputs, below the 470-512 MHz range of the current treaty, so you're probably right a treaty modification would be needed for coordinated cross-border USA<->Mexico GMRS operation. Taking another look though Part 95 radio services, though the FCC removed the 250 km contact limit for 27 MHz CB, the only country listed with permissible cross-border contacts at 27 MHz is Canada's CB service (General Radio Service). https://www.ic.gc.ca/eic/site/smt-gst.nsf/vwapj/ric18-issue4-oct08.pdf/$FILE/ric18-issue4-oct08.pdf The clincher seems to be Part 95.1733(a)(9) which prohibits foreign (non-US) contacts for GMRS: § 95.1733 Prohibited GMRS uses.(a) In addition to the prohibited uses outlined in § 95.333 of this chapter, GMRS stations must not communicate: (9) Messages (except emergency messages) to any station in the Amateur Radio Service, to any unauthorized station, or to any foreign station; Anyway, good to know. I live in the southwest (New Mexico), so I guess we can't reply to Mexican operators that pop up on the Southwest linked system until some entity works the cross-border treaty issue.
  7. An interesting question came up at the end of the national net on Sunday, Nov. 29. An operator from Monterrey, Mexico near the tip of southern Texas came on the system, and asked about cross-border linking (presumably via Internet) of a repeater he is setting up for the national net on Sundays. The topic is to be taken up on the Wednesday Tech Net on Dec. 2. Anyone have any rules references for this? I think the Mexico repeater would have to be covered by their local laws. Here's a link to some info on Mexico's equivalent of CB/FRS and other "licensed by rule" services: http://www.ift.org.mx/espectro-radioelectrico/bandas-de-frecuencias-del-espectro-radioelectrico-de-uso-libre but is cross-linking a foreign UHF repeater into a U.S. GMRS net via the Internet permissible under the Part 95 rules?
  8. There are any number of "selective calling" schemes that can be programmed into business band radios and repeaters for private talk groups. Here's a partial list. https://en.m.wikipedia.org/wiki/Selective_calling Sent from my SM-G950U1 using Tapatalk
  9. The MXTA26 is not included with any radio by default, though it may be sold as part of a kit by various online vendors. I purchased the MXTA26 stand-alone from Midland directly. Its MSRP is $40 where it is competitive with similar single-band UHF co-linear "gain" antennas for the land-mobile radio market from Larsen, Laird, PCTEL, Tram-Browning, etc. So Midland is going after the "serious operators" market with this antenna. The oddity here is that the MXTA26 is marketed as "factory tuned" whereas most land-mobile UHF antennas are "field tuned" i.e. you have to cut the antenna to resonance for your given mounting configuration. I was curious how well "factory tuned" would actually work given the large variation in mounting configurations for land-mobile UHF antennas. Answer is the MXTA26 "factory tuned" antenna isn't resonant on the GMRS band for certain mount configurations. Not a big surprise, just providing the data in a mini-review to back up this fact. The MXTA26 is sold as a stand-alone NMO mount "factory tuned" antenna. Here's the link: https://midlandusa.com/product/micromobile-mxta26-6db-gain-whip-antenna/ You need to supply a separate NMO mount usually. It may be available in kit form i.e. radio/antenna/mount from various on-line vendors. But it was designed and marketed to compete with other single-band UHF NMO mount antennas, where you choose your NMO mount independently of the antenna.
  10. Nah, the mount is fine. See the review of the Browning BR-173-S commercial land-mobile antenna I just posted. The Browning achieved 1.2:1 SWR at 463 MHz on the same mount. There's a couple of comments in the Midland store reviews of the antenna on Amazon that the antenna comes too short from the factory, so I'm not the only one seeing it resonate above the GMRS band. Again, the resonant point is mount-specific, but if the antenna came a bit longer from the factory, you could cut it to resonate on the GMRS band for a wider range of mounting configurations. Maybe the MXTA26 is factory cut to be resonant on the GMRS bands for center-of-roof placement on a Midland NMO mag mount? That's a pretty limited configuration, though. Many people will use a NMO antenna on a front fender or rear trunk/hatchback/tire rack mount these days, even though the NMO 3/4 inch hole mount was originally designed for center-of-roof placement.
  11. I picked up a Browning BR-173-S spring base UHF antenna from a local business-band radio installer. This is a cut-to-tune (not a factory tuned) antenna. I have it mounted on a small coupe with a Diamond K400 series NMO trunk lip mount. Using a RigExpert AA-650 Zoom analyzer, I cut the antenna down to a 1.23:1 SWR on 462.8 MHz. This is my primary GMRS mobile antenna. I cut it to resonate at ~463 MHz rather than ~467 MHz as I usually operate simplex, not repeaters. A SWR sweep of the tuned antenna is attached.
  12. I have a Midland MXTA26 obtained from the official Midland store on Amazon. It is mounted on a Diamond K400 series trunk lip mount on a small coupe. It resonated around 481 MHz out of the box. Extending the whip as much as possible while still maintaining a grip via the 2 set screws in the whip base, the lowest I can get the resonant point is 478 MHz. It is worse than 1.8:1 SWR at the GMRS 463 MHz frequencies. So I'd say the antenna is cut a bit short at the factory for certain mobile mounting configurations, and there isn't a way to lengthen it. I'm keeping it as a backup antenna. I picked up a tunable (cut to tune) antenna from a different manufacturer from a local land-mobile radio installer, and am using that antenna as primary. The MXTA26 SWR sweep across the UHF band from a RigExpert AA-650 Zoom antenna analyzer and picture of the mounting configuration are attached.
  13. My experience with radio programming is that the CCR Part 95 software is OEM specific, and the mainstream vendor Part 90 software is unobtanium for mere mortals. Sent from my SM-G950U1 using Tapatalk
  14. Anyone know what the transmitter FM deviation is for "out of the box" MXT275 micro-mobile transceivers in "repeater" mode on channels 15-22? Is it the +/- 2.5 kHz (narrowband) FRS deviation, or a more typical +/- 5 kHz (wideband) GMRS deviation? I know the MXT400 transmitter FM deviation can be set via programming cable, but haven't seen any discussion on the MXT275. The MXT275 manual is silent on such matters.
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