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JLeikhim

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Posts posted by JLeikhim

  1. On 12/19/2023 at 10:38 AM, Sshannon said:

    I have the full color Garmin Rino and it is excellent.  You can load tops maps at higher resolution for areas you want to visit.  The screens are easier to see the brighter the sun.  The Rinos are high quality GPS receivers with decent quality GMRS radios built in.  The monochrome one is much less expensive, but I like the color. But they are limited to handheld radios by current regulations and the data can not be sent through a repeater.

    The proposal Gil posted is a change because it will allow mobile radios to do similar functions.

    The 50 watt mobiles will transmit on the 8 sole, repeater/simplex channels and create havoc for other GMRS users. Bad idea, even for "rural" .

  2. There is only one day left to post YOUR comments on this critical item. Only 6 so far have commented in dissent. You can make an express comment filing if you wish . I did, and mine was wordy.

    My old boss had a saying about allowing a camel to put his nose in the tent. Eventually you have the whole camel in your tent. Midland is interested only in maximizing sales of product, not protecting the GMRS service. You might like their product, fine, but Midland wants to distort the rules to sell product, without any regard to the technology that has existed since the inception of GMRS many decades ago. Point of fact, they have no problem ignoring that GMRS is a wide band 16K0F3E emission and sell radios that are narrow band and are reduced in performance. They did some trickery on one already certified radio model and claimed it could be made wide band via software. If so, it would be illegal to do so. So far I have no evidence that the software slipped out the back door, actually works. That is the company Midland.

    1) More digital noises on the channels will become very annoying. I can tell you from experience, that the rodger beeps from FRS radios at the national parks will drive you nuts. Now with 50 watts and persistent GPS locations from 5 or 10 ATV's and voice communications will be impossible. Yes you can use PL but, if you are in the wilderness, sometimes it can be a safety net to listen in CSQ. Midland can do all this SMS messaging and geolocation on 900 MHz ISM band like their competition in this space. They can have mesh networking as well and extend the footprint substantially.

    2) A digital voice option in GMRS would be great. However Midland describes a 4:1 TDMA solution that will not work in simplex which is 99% of their market. They are apparently un-knowledgeable about this and have thrown it in for arguments sake. If Midland were to develop such a product, it would not be a standard like P25 or DMR, it would be proprietary and incompatible with everyone else (Like Yaesu C4FM Fusion). If the radios are strictly digital, there would be no interoperability with existing FM wide band radios. Good luck on calling for help with your radios as you hear only digital voice. Midland can also do this on 900 MHz ISM band like Motorola DTR. There would need to be no FCC rule changes as ISM rules are very flexible.

    None of what Midland has proposed should be approved. Especially adding digital data to high power radios.  If a digital voice option is to be considered, it should be described by the user community and should be a recognized standard like DMR and should have FM wide band mode as a primary mode of operation for interoperability with existing radio population. Frankly, a blanket approval of part 90 DMR radios, would be sufficient. But Midland wants more than that as a proprietary option will be cheaper to make and will lock in users to their crappy brand.

    Please dissent on Midlands entire proposal and do so quickly. An Express Comment is fine. Just Say No to bad engineering.

    https://www.fcc.gov/ecfs/search/docket-detail/RM-11970

  3. You have one of the following:

    Bad feedline, antenna or connector causing wideband noise when transmitting.
    Loose connector in one of the above.
    A noise source nearby like a computer or monitor that is so close to the antenna that it reradiates the TX signal plus wideband noise.
    Loose mounting hardware on the antenna or mast.
    Nearby interference like an AM station or FM station mixing with TX and reradiating the RX frequency.

    This should be considered last and not at all if it works on a different antenna. Duplexer out of tune.

    Think about what might have changed...

    Sent from my SM-T350 using Tapatalk

  4. Has anyone actually tested one of these Midland radios after programming "wide band" with Chirp or any other software? By test, I mean looking at the deviation of the transmitter with a deviation meter and measuring receiver acceptance bandwidth.

    I think that folks are being fooled by a check box in the software that does nothing.

    Sent from my SM-T350 using Tapatalk



  5. This is NOT the way to be doing that.
    You need to find some 75 ohm cable and cut two EQUAL lengths of it and put the required connectors on it. 
    Then you use a Tee connector fed with a 50 ohm cable.  But the two 75 ohm cables have to be the same length.  If you split the power in a divider, then only 50% of the total signal goes to each antenna.  It will maintain the correct impedance, but cuts the power in half.  When you run the two pieces of 75 ohm cable you correct the impedance mismatch that would be 25 ohms (2 50 ohm loads in parallel) by adding 25 ohms of impedance to each leg. 
    And I would be looking for proper cable for this like RG11 with a copper shield and NOT TV cable.  TV cable typically will not take solder as well and is a pain to terminate.
     
    Both schemes apply 50% ( less resistive losses ) power to each antenna.

    Sent from my SM-T350 using Tapatalk

  6. You can test the effects of double vocoding rather easily by connecting a simplex DMR or P25 radio to an Argent Data Systems simplex repeater. The simplex repeater will record demodulated digital audio (analog) and then repeat the analog signal through the transmit vocoder. In choosing a simplex repeater, choose the highest sampling rate as not to introduce distortion .

    While one can make a duplex P25 repeater from two radios, making a duplex DMR repeater is a huge challenge as in the duplex mode, subscribers require synchronizing with the repeater transmitter.

    Sent from my SM-T350 using Tapatalk



  7. I was hoping they were squirting ANI/ALI along with caller ID these days.  I have noticed a huge delay on answering calls these days on my VoIP residential line. Also some long string of numbers along with phone number on my phones caller ID. It would be nice to be able to discern the spoofed calls, I suppose mostly from India.

    I am familiar with older models, Zetron model 48B, 38 etc tone panels. Also 6/26 fire station alerting. A great company with niche products.

  8. 4 hours ago, PACNWComms said:

    There are some holes in the collection, especially with mobiles. I am the traditional radio hoarder, and have mobile data terminals, and lots of gear around, but most of it doing something. I would say about 85-90% Motorola thanks to the oil industry and planning for hardware replacement.

    Then Kenwood/EF Johnson/Zetron.....working for them helped that a bit, corporate "yard sales" where day three everything went for free as ""e-waste" costs the company money. My Zetron ALI display shows the entire caller ID data, as the entire data stream is sent, but consumer grade equipment only shows name and number, two lines.

    What model ALI? What else might one see in the data? I get a lot of robocalls and it would be interesting to see what they cannot spoof.

  9. 5 hours ago, gman1971 said:

    Added the Astro System Saber, but there isn't much info really. Certainly not as detailed as the newer radios spec sheets are. 

    FYI. The info I sent you was for Systems Saber, not Astro Systems Saber. There is an Astro Saber, but it is a different animal and not Part 95 certified.

    The Systems Saber is wideband only so there are not as many specs. The standards were TIA-603A.  And it has no GPS or Bluetooth etc. Its just a radio!  If you use a modern lithium ion battery with it you can attain 5500 mAh and the radio is nearly 6 oz lighter. the duty cycle at 5/5/90 is about 20 hours. There are 2200 mAh lithium ion batteries that are shorter and give about 9 hours.

  10. The earlier Systems Sabers and analog Sabers are modular so you can change band splits by swapping a few modules and retuning. I have done this with several surplus govt split IRS radios.

    The Astro Saber is a bit too tall for my taste. I have a couple of those but prefer the Systems Sabers.

    I wish Motorola had continued with the Saber form factor. The later Astro XTS and APX radios are sort of bizarre and bulbous in styling.


    Sent from my SM-T350 using Tapatalk



  11. Lots of info here.

    http://www.onfreq.com/syntorx/

    I recently revived 3 of the low band radios and they are fine. Even have DES-XL capability with infinite code retention.

    I had Andy Brinkley , Brinkley Electronics in North Carolina program my code plugs. You will have to determine which firmware you have and he will burn you code plugs to match 32, 64 or 128 channels. The control head needs an 8K memory for 64 or 128 channels.

    In my case I bought a 128 channel upgrade. The price was reasonable.

    If you are doing this for GMRS you can get by with 32 channels and 16 tone MPL. There is a simplex button DIR for talk around.

    GMRS is wideband unless you drink the Midland koolaid . Set the power to 50 watts and you will be fine.

    Orange and green wires behind control head are for ignition sense. There should be a white or clear molex connector for the speaker. If this doesn't look quite right, you may have a siren cable for a DEK unit, not a radio cable. Check you part numbers on the onfreq website before powering it up.


    Sent from my SM-T350 using Tapatalk







  12. I posted this on another forum, but I figured it might be helpful to post it here as well. This is a comparison of some of the top of the line radios in the LMR/LEO market. Including the mighty APX8000, and the HT1250 from the 20th century...
    image.thumb.png.d87b834a79c07017b74a157ef05eddc5.png
    Can you add the UHF Systems Saber? I know it is a unicorn, but it is probably one of the few with Part 95 certification. If you need a catalog sheet I will send you one.

    Sent from my SM-T350 using Tapatalk

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