Lscott
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Posts posted by Lscott
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2 hours ago, Sshannon said:
So, after that long explanation, how does this displayless DMR radio allow a user to select channels? How does a person know which channel they’re on?
Likely the same way I have to do it for my TK-D340U radios.
https://forums.mygmrs.com/gallery/image/291-tk-d340u-front-and-back-2jpg/?context=new
The radio has 32 channels total split 16 between two zones. I printed out a cheat-sheet I created in Excel. It does have voice announcements, but only for changing zones and channels. Not really much help.
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2 minutes ago, WRYS709 said:
Yes, the notes from the PNW group indicate that this is a groundless connector, too!
For inexpensive DMR, it is still hard to beat the Radioddity RD-5R a/k/a Baofeng DM-5R: uses all the same accessories, including batteries, of the UV-5R, 5 watts, analog too including GMRS, MURS, 2 meters and 70 cms; full Tier-2 and now works with the "OpenGD77" firmware project.
Some of those early Baofeng's were not Teir-2 compliant. They spammed both time slots on the repeater and were banned by DMR repeater owners to use on their machines.
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20 hours ago, WRXB215 said:
Here's one that might work for you.
I have the TDMA capable version of that amp. If you look at the FCC ID in the photo and check it out, the amp is only certified for Part 90! Oops.
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6 minutes ago, WRXB215 said:
LOL! @Lscott your questions are always way over my head. Glad there are people here that can answer.
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.
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Just now, tweiss3 said:
Nope, no help. I figured out how deep I was last week when I spent some time updating my inventory spreadsheet. It's pretty bad.
Knowing some of the stuff you have your pockets are deeper than mine.
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2 minutes ago, WRXB215 said:
I still like the Baofeng but WOW! the Kenwood sounded significantly better.
Kenwood radios are known for their good audio quality.
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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.
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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.
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On 1/24/2024 at 8:55 PM, WRKC935 said:
If you read in here enough, you will see people that will claim they are sending their' faulty' radio back because it doesn't do the full 50 watts it's advertised at. It's only doing 46 or 48 watts on their meter.
Do they send it back if it does more?
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1 hour ago, WSAK691 said:
Is there a help group for me?
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
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On 1/27/2024 at 4:09 PM, Sshannon said:
@LScott is a Kenwood aficionado. I think he likes the 8173.
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
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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.
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5 minutes ago, WRYS709 said:
OK: It came in yesterday and using my FTDI USB K-1 cable, it programs pretty easily on both digital and analog.
And it seems to work fine in analog simplex and repeaters and digital simplex (perhaps, as I only purchased one, but one can hear the "picket fencing" from its transmission digital simplex when one listens on an analog receiver), but digital DMR repeaters seems to be problematic so far.
But later today I will initiate some more experimentation on both digital simplex and digital DMR repeater.
Thanks for the update.
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32 minutes ago, wrci350 said:
The letter says that the affecting repeaters had to drop to 5W while further investigation was done. The letter (and following thread) was from 2007. I read your "more headaches for 70cm" post and thought this was some "new" problem ... which it is not.
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.
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20 minutes ago, wrci350 said:
That installation has been there since 1980 I think, so this isn't anything new. Ham radio is secondary on 70cm.
I think most hams that operate on 70cm use a mobile radio with a power supply, so they are running less than 50W anyways. Even the shack-in-a-box radios that do 100W on HF only do 45 or 50 on 70cm.
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
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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. -
20 hours ago, Sshannon said:
Did you read paragraph where they mentioned rejecting comments suggesting TDMA digital modes for GMRS? It’s pretty clear.
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.
- WRUU653 and SteveShannon
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1 hour ago, Sshannon said:
@LScott is a Kenwood aficionado. I think he likes the 8173.
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
- WRXB215 and SteveShannon
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And more headaches with 70cm band.
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1 hour ago, WRYS709 said:
since they are FRS users, they have little or no concept nor concern about their proximity to repeater channels. They just transmit and receive.
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.
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1 hour ago, WRYS709 said:
An interesting observation, but still not the reason why the FCC limited Channels 8-14 to 1/2 watts historically.
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.
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10 minutes ago, WRYS709 said:
BUT when the FCC did expand FRS to also allow Channels 1-7 at 2 watts; these are also "interstitial channels" of repeater output channels and based upon power and geographical proximity these channels can also cause interference to GMRS repeater users by interfering to their ability to hear the repeater outputs and by definition even more so at 2 watts than only 1/2 watt.
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.
Super Cheap Chinese DMR Radios, Experience?
in Equipment Reviews
Posted
This might help.
https://www.afb.org/blindness-and-low-vision/using-technology/assistive-technology-products/braille-printers