Questions about DMR

kayn1n32008

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It is hard to find XTS that does not have FPP,FDNY stuffed into it by some got to have it all in the flash. Took me a long time to pick up my XTS that was not whored out.
Honestly, the XTS series have been EoL for long enough, it really doesn't matter what the flash is. Certain software tools are so easy to find, that the flash is trivial. It's still fun to see the 'teknishuns' that have no idea about the XTS series, and stuff "all options turned on" codeplugs in. Majority of trunk systems are trying to get Phase 1 only radios off to either go to Phase 2, or implement features that are not included in ASTRO25 radios firmware.
Since the initial programming of my UHF XTS, VHF XPR mobile and XG-100P, some having been with me several years, they have only been reconnected to pc 1 time. That was to change my DMR Id that they decided needed to be changed they issued way back when.
My XTS2500 UHF-R1 is actually a PRC-153. It now has proper back light. It also got a much more useful flash, done the ugly way, because its only used for ham radio. My VHF XTS2500 has a reasonable 9600baud trunking flash, as it came out of Quebec, and was most likely used on the RENIR. I was fortunate that both are model 3 and came with UCM's with algo's. These radios are quite happily chugging away in their new lives.

I'm still tweaking my codeplugs, Repeaters change, new ones come along.

I have constants with my radios though. On VHF, I have a zone of the 146MHz simplex channelized, and another zone of the 147MHz simplex channelized, according to the band plan. I have done the same for 70cm as well.

If you plan, and think ahead, FPP really isn't needed. I also cheat, and I usually bring my laptop with me when I travel, along with the 4 programming cables I need for my XTS/XPR radios. Even my Anytone, I don't FPP. At all.
 

Spider255

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I have a few DMR questions as I am also getting into DMR, I hope I'm not hijacking this thread but I thought it would be better to ask on this thread rather than creating another thread for the same topic.

Here is my question... Is it good practice key up to activate a talk group for listening?
 

Spider255

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Feel free to add some constructive links for the OP rather than dissing an informative document, no matter the age. There are many of us that still support real repeaters to a C-Bridge that are utilized daily, including myself.

View attachment 193834
Thanks for posting these, I always find it helpful to see some lists of talk groups as there are so many to pick from and seeing a short list like these helps others to get started. I have most of these programmed in to my DMR radios when I brought my first lot of DMR radios some years back. I also like using DMR repeaters and I'd fully support them. DMR hot spots are fun but I also think DMR repeaters offer a better feeling of radio.

I got confused thinking that those were the old talk groups because there are now others that are more active like TG1 & TG91 or TG3 & TG93 for example. I knew about TAC310 from YouTube videos and people telling me that TAC310 was no longer used but its back now. I heard it on the DMR Hoseline and I will be adding it back to my code plug.

I was thinking earlier that it be cool if the ISS had a DMR Talk Group, maybe they will in time.
 
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popnokick

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I have a few DMR questions as I am also getting into DMR, I hope I'm not hijacking this thread but I thought it would be better to ask on this thread rather than creating another thread for the same topic.

Here is my question... Is it good practice key up to activate a talk group for listening?
Not only is it "good practice" it is totally necessary for SOME TG's on SOME repeaters. So how do you tell when a PTT key up / kerchunk is necessary on a repeater (I'll address hotspots in a moment)?
First, you need to know if you're using a repeater that is on the cBridge network or on Brandmeister network. If the latter then nearly any TG can be activated on either slot. However, it's "good practice" to be aware of what TGs the sysop / admin has assigned as "static" (permanent) TGs on each slot. This way you're not doing something irritating like keying up your statewide TG on Slot 2 when it has already been assigned as a static TG on Slot 1.

As a general rule, Brandmeister repeaters follow an "explicit allow" rule for all TGs, and cBridge repeaters follow an "explicit deny" for all TGs that are not statically assigned by the sysop. Two very different and opposing ways of looking at DMR repeater operations.

But how do you know what DMR repeaters are in your area, which backend network are they on, and what TGs are assigned as static? This is where better repeater directories come in, such as RepeaterBook.com, your local repeater coordinating council's directory, delmarvardmr.com (for PA, MD, and VA)... and similar directories.

If the repeater is on the cBridge network you absolutely MUST find out what TGs have been statically assigned on each slot... because you won't be able to use anything other than those TGs.

And that brings us to hotspots. Hotspots behave sorta like Brandmeister repeaters in that you can PTT key up ANY TG you wish. However, as the sysop of your own hotspot you can also assign almost any TG as static (except 310-312) which will cause it to be continuously monitored. Otherwise, the dynamically keyed TG will drop off your hotspot in about 10-12 mins.

In this reply I've addressed only the cBridge and Brandmeister networks. There are several others (TGIF, etc) available and their policies may differ. More info on Brandmeister is available at help.brandmeister.us
Also a good read for cBridge operations is delmarvadmr.com (even if you are not located within that geography).

Now go read and learn!
 

kayn1n32008

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I have a few DMR questions as I am also getting into DMR, I hope I'm not hijacking this thread but I thought it would be better to ask on this thread rather than creating another thread for the same topic.

Here is my question... Is it good practice key up to activate a talk group for listening?
Depends on the repeater owner. Our club doesn't care. I key up on TG91 just to listen quite often. Unfortunately it drops with no inbound RF activity, so after 5 or 10 minutes, if there has been no inbound RF to the repeater, it drops the talkgroup, even if there is network based activty.
 

kayn1n32008

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I was thinking earlier that it be cool if the ISS had a DMR Talk Group, maybe they will in time.
I'm not holding my breath. Besides the TDMA propagation timing issues, the ham radio currently on ISS is a Kenwood mobile, modified for space flight.
 

Spider255

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One thing that puts me off DMR slightly is the need for a hot spot... How reliable are they, and do they go wrong often?

DMR hot spots are expensive for what they are but there are cheap routes to go with like a Raspberry pi which works out to around 60 UK pounds to build. Raspberry Pi's have always struck me as single board computers designed for temporary projects where you'd build something with one, then later build something else etc I've not looked upon a Raspberry Pi to use in something permanent as I know from using them in the past that things do go wrong with them, SD cards become corrupted, something running on an SD card 24/7 could mean something could go wrong meaning I could be without DMR even after spending lots of money on getting setup properly with a hot spot.

I understand I literally have no choice that there really is no other way if I want to stay active making contacts because there isn't really much going on with traditional analog and simplex in general above HF anymore. DMR is the way and is where people are. My local DMR repeaters coverage isn't so great no matter what antenna is used, I often have to go out portable to get in to it without having a whole lot of packet loss so a hot spot is really a must have.

The other thing is that I don't like leaving things switched on when I'm not home so can the hot spot be switched off without having issues switching it back on again?

I've got a fair idea of how hot spots work in terms of how they connect to the wifi router and roughly how to configure, set them up but I still don't know a whole lot about them.
 

EuropeanUser

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One thing that puts me off DMR slightly is the need for a hot spot... How reliable are they, and do they go wrong often?

DMR hot spots are expensive for what they are but there are cheap routes to go with like a Raspberry pi which works out to around 60 UK pounds to build. Raspberry Pi's have always struck me as single board computers designed for temporary projects where you'd build something with one, then later build something else etc I've not looked upon a Raspberry Pi to use in something permanent as I know from using them in the past that things do go wrong with them, SD cards become corrupted, something running on an SD card 24/7 could mean something could go wrong meaning I could be without DMR even after spending lots of money on getting setup properly with a hot spot.

I understand I literally have no choice that there really is no other way if I want to stay active making contacts because there isn't really much going on with traditional analog and simplex in general above HF anymore. DMR is the way and is where people are. My local DMR repeaters coverage isn't so great no matter what antenna is used, I often have to go out portable to get in to it without having a whole lot of packet loss so a hot spot is really a must have.

The other thing is that I don't like leaving things switched on when I'm not home so can the hot spot be switched off without having issues switching it back on again?

I've got a fair idea of how hot spots work in terms of how they connect to the wifi router and roughly how to configure, set them up but I still don't know a whole lot about them.

You only need a hotspot if there are no DMR repeaters near you that are connected to the network you wish to use.

I have had my home built hotspot running for over 2 years without issue. A cheap kit imported from china and I just provided the Raspberry Pi Zero 2 W with the official power supply and did the soldering of the pin headers.

SD cards can become corrupted but any project made to run long term on a Raspberry Pi should have made consideration to limit writes to the card. Pi-star has not been an issue. I have Raspberry Pi board that have run for 5+ years on the same microSD card. I use quality cards from Sandisk. If the card fails you just get a new card, flash the image and restore the recent backup you hopefully made of your config.

You can switch off the hotspot. Either from the web interface or by configuring it for remote commands and activating a talkgroup ID specified in the config. Then when it's off you can unplug it. Unplugging without first shutting down the OS may cause file corruption.
 

Spider255

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You only need a hotspot if there are no DMR repeaters near you that are connected to the network you wish to use.

I have had my home built hotspot running for over 2 years without issue. A cheap kit imported from china and I just provided the Raspberry Pi Zero 2 W with the official power supply and did the soldering of the pin headers.

SD cards can become corrupted but any project made to run long term on a Raspberry Pi should have made consideration to limit writes to the card. Pi-star has not been an issue. I have Raspberry Pi board that have run for 5+ years on the same microSD card. I use quality cards from Sandisk. If the card fails you just get a new card, flash the image and restore the recent backup you hopefully made of your config.

You can switch off the hotspot. Either from the web interface or by configuring it for remote commands and activating a talkgroup ID specified in the config. Then when it's off you can unplug it. Unplugging without first shutting down the OS may cause file corruption.
Thanks... that has reassured me, a lot of things I'd need to do to prepare... yep making a back up copy of the SD card is very important something I have thought about. I am a bit OCD on safety when it comes to leaving things on 24/7 so finding a decent PSU to power it where I wont have to worry about when I'm not home. I guess its more about getting use to new things...
 

EuropeanUser

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Thanks... that has reassured me, a lot of things I'd need to do to prepare... yep making a back up copy of the SD card is very important something I have thought about. I am a bit OCD on safety when it comes to leaving things on 24/7 so finding a decent PSU to power it where I wont have to worry about when I'm not home. I guess its more about getting use to new things...

All you really need to do is download a configuration backup from within pi-star after making changes.

I am a huge safety advocate and I don't use cheap power supplies. I have seen the insides of too many to even consider using one. Non-existent isolation gaps, no proper protection for overvoltage, overcurrent or any regards to protection between primary and secondary. I trust the official Rasperry Pi power supplies. They have been rock solid and seem to be well designed.

The OLED display on my hotspot has terrible image retention after two years and is almost unreadable. Thankfully it isn't needed, just nice to have. If you want a display I would recommend going with one of the larger LCD options.
 

K9KLC

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One thing that puts me off DMR slightly is the need for a hot spot... How reliable are they, and do they go wrong often?

DMR hot spots are expensive for what they are but there are cheap routes to go with like a Raspberry pi which works out to around 60 UK pounds to build. Raspberry Pi's have always struck me as single board computers designed for temporary projects where you'd build something with one, then later build something else etc I've not looked upon a Raspberry Pi to use in something permanent as I know from using them in the past that things do go wrong with them, SD cards become corrupted, something running on an SD card 24/7 could mean something could go wrong meaning I could be without DMR even after spending lots of money on getting setup properly with a hot spot.

I understand I literally have no choice that there really is no other way if I want to stay active making contacts because there isn't really much going on with traditional analog and simplex in general above HF anymore. DMR is the way and is where people are. My local DMR repeaters coverage isn't so great no matter what antenna is used, I often have to go out portable to get in to it without having a whole lot of packet loss so a hot spot is really a must have.

The other thing is that I don't like leaving things switched on when I'm not home so can the hot spot be switched off without having issues switching it back on again?

I've got a fair idea of how hot spots work in terms of how they connect to the wifi router and roughly how to configure, set them up but I still don't know a whole lot about them.
I only do DMR simplex or thru one local repeater, and at that I rarely use anything but Local 9 which is the local repeater only. Have used it at work, HT to HT also. DMR is simply another mode, not necessarily needing internet, or any other infrastructure to be used.
 

Spider255

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All you really need to do is download a configuration backup from within pi-star after making changes.

I am a huge safety advocate and I don't use cheap power supplies. I have seen the insides of too many to even consider using one. Non-existent isolation gaps, no proper protection for overvoltage, overcurrent or any regards to protection between primary and secondary. I trust the official Rasperry Pi power supplies. They have been rock solid and seem to be well designed.

The OLED display on my hotspot has terrible image retention after two years and is almost unreadable. Thankfully it isn't needed, just nice to have. If you want a display I would recommend going with one of the larger LCD options.
Can a regular LCD VGA PC monitor via an HDMI adapter be hooked up to it? I have a few spare LCD screens laying about so maybe using one would add a nice touch rather than looking at the OLED display?
 

tweiss3

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Can a regular LCD VGA PC monitor via an HDMI adapter be hooked up to it? I have a few spare LCD screens laying about so maybe using one would add a nice touch rather than looking at the OLED display?
I don't think so. You are better off looking at the dashboard on your computer.
 

popnokick

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Can a regular LCD VGA PC monitor via an HDMI adapter be hooked up to it? I have a few spare LCD screens laying about so maybe using one would add a nice touch rather than looking at the OLED display?
You can plug an HDMI video cable into the Raspberry Pi running the hotspot but it will NOT display the MMDVM hotspot dashboard, regardless whether you run WPSD or Pi-Star.
 

N4VKF

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So...when I look up a talkgroup, the databases all have a talkgroup number but not a timeslot or color code. How do I get that information? I'm trying to get Droidstar working.
You don't need a CC or TS for droidstar. You can't connect to a repeater via droidstar.
 
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