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Lscott

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Everything posted by Lscott

  1. You would be surprised how much I have to struggle to digest some of the stuff too. Those standard documents I don't think were written for humans to read.
  2. Knowing some of the stuff you have your pockets are deeper than mine.
  3. Kenwood radios are known for their good audio quality.
  4. Just about every DMR radio out there is a Tier-2, or Tier-3 if trunking is used. DMR is usually thought of as just TDMA. There is DMR Tier-1 which operates in FDMA mode, referred to as a continuous transmission mode. The only ones I know that do are the license free digital PMR446 radios in the EU. Anyone else know of a DMR Tier-1 radio? I'm curious about how a Tier-1 and Tier-2 radio would interoperate. Also is there really any difference between a Tier-1 radio and a Tier-2 radio when operating in simplex mode? I've read several different opinions about it. Some say it's single slot while other claim it's double slot. Then there is the issue of DCDM, Dual Capacity Direct Mode. And, apparently there are two flavors of that too. I've been digging through the technical documentation and it's sketchy what Tier-1 really does, and if its compatible with Tier-2. I found the attached in one of the ETSI DMR standards documents. In the documentation "BS" refers to a Base Station and "MS" refers to a Mobile Station.
  5. As far as I know nobody makes an amplifier that's Part 95E certified. There are plenty of Part 90 stuff that could work.
  6. Bummer. I have an old Kenwood HT, TK-370, with a stud type antenna port. At least that one has a ground ring for the coax shield insulated from the center stud recess on the port. I still had to grind down the stud on the adapter so the ground ring would make contact with the ground ring on the radio's antenna port. The adapter would allow the use of a standard BNC type connection.
  7. Do they send it back if it does more?
  8. Likely not. I could use one too. Stop before it gets too crazy. Trust me on that. https://forums.mygmrs.com/gallery/image/249-934916052_radiocollectionjpg/?context=new
  9. Actually it’s the TK-3170. Great HT for GMRS carry. Can push it out of band for use in the Ham 70cm band. It’s also Part 95 certified too. https://forums.mygmrs.com/gallery/image/263-tk-3170jpg/?context=new If you don’t care about FCC certification there other Kenwood HT’s you can try. Mainly they are FM and some digital mode, the later usable on the Ham bands. The ones with DMR might be most attractive for Ham usage. I have all of the below FM/Digital models in the UHF and VHF versions except for the NX-1300 so far. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/?context=new https://forums.mygmrs.com/gallery/image/251-nx-300jpg/?context=new https://forums.mygmrs.com/gallery/image/255-tk-d300e-fmdmr/?context=new http://comms.kenwood.com/common/pdf/download/TK-5220_5320_Specsheet.pdf I have a few of the TK-3180’s. Nice radio with good features and 512 channels. https://pdfs.kenwoodproducts.com/10/TK-2180&3180Brochure.pdf Even so I still have a preference for the TK-3170. The trunking version, TK-3173, is also very nice and uses the same software as the TK-3170. I have several of those. https://pdfs.kenwoodproducts.com/12/TK-3173BrochureRev.pdf
  10. If the antenna port is one of those funky screw stud type my interest is sort of gone. It’s the same deal with the Motorola XPR-7550E HT. Super radio. The stud antenna port killed my interest in one. Also there is no decent adapter either that isn’t a mess to use. I’ve seen one but you have to run a ground strap from it to the chassis. I use my HT’s mobile and while out traveling. So having a way to use an external antenna is a primary requirement for me.
  11. Of course there are the commercial interests that are always looking for away to poach more spectrum from various ham bands. There is all sorts of low power garbage around 433MHz. A local company by me had interference issues with their alarm systems they sold. Contacted the FCC who traced it to a Ham ATV station a few miles away on a 16 storie apartment building. They shut it down and did their investigation. Found nothing wrong and allowed the station to resume operation. The head dude at the alarm company asked the station owner in for a talk. He asked how much power was being use. It was about 100 watts PEP. Then asked how much could they legally run. The reply was 1500 watts PEP. The dude nearly had heart failure from what the ATV station owner told me. Then Chrysler had a similar issue with their tire pressure monitors they were testing. Got to a certain area on I-75 and they F’ed up from the same source. At least they figured out the cause and understood it was their problem to fix. My post didn’t imply there were new problems with 70cm. Just wanted to point out another specific serious one the prior poster didn’t mention. I’ll also bet most hams have never heard about it. I suspect many hams don’t know we are only secondary users on the band, and if they do who is primary.
  12. Some of the problematic repeaters had to reduce power output to only a few watts to keep the military happy. https://www.eham.net/article/16786
  13. Trying to chase down the correct technical documents is a bit challenging. Also many of the EU license free radios, DMR PMR446, sold don’t really use the Tier-1 FDMA standard, as required. They use the TDMA Tier-2 since it results in better battery pack life. Oh, one other thing with DMR, there is theoretically a range limit due to the TDMA nature of the mode. It’s covered in the technical documentation. That’s an interesting topic all on its own.
  14. There is a FDMA version of DMR, called Tier-1, used the EU’s license free band of 446.0 to 446.2 MHz. This link is for the ETSI document for dPMR specifications. http://dmr446.hamstation.eu/docs/ETSI-TS-102-490.pdf The DMR Tier-1 specifications are similar but use a 12.5KHz channel. Most of what we use here is Tier-2, conventional, or Tier-3, trunked.
  15. Actually it’s the TK-3170. Great HT for GMRS carry. Can push it out of band for use in the Ham 70cm band. It’s also Part 95 certified too. https://forums.mygmrs.com/gallery/image/263-tk-3170jpg/?context=new If you don’t care about FCC certification there other Kenwood HT’s you can try. Mainly they are FM and some digital mode, the later usable on the Ham bands. The ones with DMR might be attractive for Ham useage. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/?context=new https://forums.mygmrs.com/gallery/image/251-nx-300jpg/?context=new https://forums.mygmrs.com/gallery/image/255-tk-d300e-fmdmr/?context=new
  16. And more headaches with 70cm band. https://www.arrlsacvalley.org/pave-paws
  17. So GMRS as a licensed service that's allowed to run much higher power everywhere else and wide-band is limited to to same tiny 0.5 watts and narrow band. Makes no sense until you consider the interference issue with the repeater input frequencies. The FCC in 2017 increased FRS to 2 watts EXCEPT for those channels. FRS was also initially limited to 0.5 watts. If the desire was to keep FRS as a low power short range service they would have kept the 0.5 watt limit on all channels. They didn't. Of course allowing GMRS users to run up to 5 watts, or 50 watts in some cases, is the carrot to get people to fork over $35 to the FCC for a license and enjoy the perks FRS users don't get. FRS users pay nothing to use the spectrum. Remember that GMRS also has interstitial channels, shared with FRS, 1 through 7. However nether are limited to the same tiny 0.5 watts. GMRS is even allowed wide-band on them. Any potential interference on the repeater output channels would be due to simplex stations and would be over a much more limited range as well. The simplex station(s) could simply switch to another simplex channel to eliminate any interference. Switching to another channel in the range of 8 though 14 just ends up being next to another repeater input frequency. So, switching to one of those doesn't really fix the interference on a repeater input frequency issue. Most of the available repeater channels are now home to various wide area coverage machines in my location. Two can't be used because we're past the FCC "Line A" mark. Your comment that "FRS users have no concept nor concern about their proximity to repeater channels" explains why they are limited to 0.5 watts and narrow-band. If there was no concern the FCC wouldn't have kept the power and bandwidth restrictions in the first place on those channels when they increased the power limit for the other channels. They had to do what the ignorant FRS users couldn't figure out for themselves, apparently, and fixed, more like tried to mitigate it, through the technical rules new FRS, and don't forget GMRS as well, radios must meet. FRS-GMRS Channels Layout.pdf
  18. The question is why is it "still currently limited" at low power and a narrow bandwidth? One other point is licensed GMRS radios also have the same exact limitation for the same reason, to reduce interference to the repeater input frequencies. It's not just an FRS thing.
  19. Which is far more serious than an FRS radio getting into a wide area coverage repeater on the input side with a 20 to 30 mile range. Once an FRS user on the output of a high power repeater gets hammered by the repeater output they typically go away to another channel. That's why it's not a really big issue compared to the input. That's how I've got rid of a few in my area.
  20. I'm not so sure this is true. The reason is the right questions are not being asked and debated fairly. See attached file. I think what should be asked with digital voice should it be allowed on all channels or restricted to particular ones? I think it should be restricted to a few selected channels. Next what digital voice mode should be used? Note I used the singular "mode" as opposed to allowing multiple modes. Standardizing on one would make the radios cheaper, more competition, and the radios from different manufactures would interoperate. People point out DMR should be used, however it might not be the best choice! I really dislike comments to the effect that anyone who proposes digital voice on GMRS is trying to turn it in to a "Ham Lite" service. No. It's about improving the quality of the communications. I was monitoring a local repeater here at work. The one station had low modulation and a weak signal. The audio was hard to understand and the beacon frying noise just made it worse. If the signal was digital very likely neither of the above would have degraded the communication experience. The typical GMRS user wants clear communications. When given the choice I doubt they would care if the signal was digital if they had good solid copy. GMRS Digital Voice - 20231127.pdf
  21. No its not a myth. In the 2017 rule changes the FCC increased the power to 2 watts on FRS EXCEPT those particular channels for a reason. FRS was never intended to have repeater access. Channels 8-14 being located between the high power GMRS exclusive repeater input channels can lead to interference and "possibly" keying up of a repeater since the frequencies overlap to a degree. That depends on how tight the repeater input filters are and how close the FRS radio is to it where enough signal can leak through them. The FCC couldn't ignore the existing population of combo radios so they left the specifications lower for power and bandwidth. That was about the best they could do under the situation.
  22. People on this forum have been severely roasted for suggesting this idea.
  23. See attached files for suggestions. Grounding Tips for the Shack.pdf Antenna System Bonding and Grounding Requirements in the USA.pdf Lightning Protection Grounding Solutions for Communication Sites.pdf
  24. Since you’re using the radios for ranch operations, a business use, you would likely qualify for one or more business “Common Itinerant and Business” frequencies which doesn’t require frequency coordination. You can also run digital voice with encryption legally for private communications. This would be an alternative to using GMRS. National Business and Itinerant Frequencies.pdf Common Itinerant and Business.pdf
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