DMR repeaters

[wa1emt]

Can someone tell me how easy is it to put up a DRM repeater.
It seems like this is the way that amateur radio is going.
Also I see that there are a ton of radios on the internet such as kirisun and zastone that list DPMR radios.
Can someone explain what that is.
Also anyone see an issue with a 900mhz repeater in the houston area.
Whats popular and whats dying as far as bands.
Thanks for your time.

 

[KD8DVR]

Well, I know of DMR becoming popular. Those kirison radios use dPMR, which is not compatible with DMR. As a matter of fact, kirison and zastone aren't even compatible with each other. As far as DRM, that is not used much by amateurs at all, but is becoming popular with shortwave broadcasters.

 

[Project25_MASTR]

What do you mean by dmr repeater? By dmr are you referring to Moto TRBO?

 

[KD8DVR]

What do you mean by dmr repeater? By dmr are you referring to Moto TRBO?

That's what I was referring to, yes. That is Motorola's Trade Name of that protocol.

 

[mmckenna]

Can someone tell me how easy is it to put up a DRM repeater.

I think you meant DMR. It's identical to putting up an analog repeater. You'll need:
Location, location, location…
Power.
duplexer
feed line
antenna support
antenna
lightning arresters, grounding, and a hundred other small bits and pieces.

It seems like this is the way that amateur radio is going.

Yes and no. Analog is still king, likely will be for a long time to come. Digital is out there, but you really need to consider what digital standard you adopt. DMR isn't the only one out there. There are P25, NXDN, DMR and different variations of each. They are not interoperable in the digital mode.

Also I see that there are a ton of radios on the internet such as kirisun and zastone that list DPMR radios.
Can someone explain what that is.

dPMR is Digital Private Mobile Radio. It's a European (ETSI) standard CAI (Common air interface). It's not compatible with DMR.
Before you get much further, I'd recommend reading up on these digital standards and decide which one you want to use.

Also anyone see an issue with a 900mhz repeater in the houston area.
Whats popular and whats dying as far as bands.
Thanks for your time.

I'm not in Houston, so I'm no help there. Not sure about your specific area, but 900MHz is pretty quiet. Not a lot of 900MHz amateur gear out there. There is some commercial stuff out there, and that is what most amateurs are using.
Choosing a digital standard and a not-so-popular band will severely limit who can access your system. This might be what you are looking for. If not, carefully consider the availability of equipment before you proceed. Newer digital standards make finding used radios a bit more difficult, especially somewhere like 900MHz. You might have better luck with 2 meters or 70 centimeter band. Bigger selection of gear out there.

 

[N5TWB]

As noticed by WA1EMT, DMR is growing. Just this past week, the DMR-MARC group noted they just issued the 10,000th digital user ID for network access. I've just ordered a DMR radio from Connect Systems that will be part of our amateur radio club's Christmas dinner door prizes. There are now three UHF repeaters in the Tulsa area using the DMR protocol so we want to encourage more people to use them.

 

[troubleshooter1]

In addition to all the requirements that mmckenna listed, you will need a reliable internet connection if you want to connect to a network, such DMR-MARC. This is a BIG problem for many repeater sites.

 

[jaspence]

DMR repeater

Motorola does have some variances from true DMR, but there are several brands of true DMR radios available. Kirisun does also make a true DMR radio. I have three Hyteras and a CS700 that work well on the Mototrbo repeaters. The biggest difference in the various types of digital is that on DMR each frequency can handle two conversations at the same time. P25, D-Star, etc. do not offer that ability. A DMR repeater can also handle analog and DMR, but not simultaneously. Setting up the repeater requires more work because of the talk groups that are part of each time slot. Internet is only needed if you want the expanded coverage such as World Wide. It can serve as a local repeater with all of the DMR functions. As suggested, the DMR-MARC web sight is a good place to start for information.

 

[Project25_MASTR]

You might also look at what's already in the state. For example, some of the hams who work for Moto shops have already started an unofficial band plan for digital systems you see in common use commercially. For example, there are quite a few 70 cm TRBO repeaters in Texas and most of them are linked together. The guys who coordinated that are wanting to get a 2m P25 network up and running. Most of those guys also stated setting up a 33 cm analog network. Do look into what's the most practical.

 

[TLF82]

I'll throw in my .02 as an active TRBO user (and repeater trustee) as well as 900mhz user.

TRBO is super popular. Lots of activity (we just hit the 10,000 user mark) with lots of talk groups to choose from depending on what you want to do (check out either DMR-MARC or DCI to see what's out there). There is a pretty decent TRBO network across Texas. I know I'd love to see a TRBO repeater in Houston as well as 900mhz... I think it would be one of those "if you build it they will come" type situations.
When the TRBO repeaters went live in the area I live in and we started advertising them several people bought radios to use. I think you would have that happen down there...

Hardest part about TRBO is getting internet access. I have free internet at one of the sites I maintain and I have a Cradlepoint with a Sprint data modem at another. I would recommend having it on one of the networks... Only things you need to do aside from the physical equipment is decide what talk groups you want and get in touch with one of the C-Bridge owners and connect your repeater to them.

If you were to put a TRBO machine up I would use UHF. Most of the nation is on UHF (aside in New England where they have to use VHF due to radar issues). In Dallas and one other place they have a 900mhz TRBO machine.

As far as 900 goes there is quite a bit of activity on it. I use it regularly and I know in Dallas, Austin, and San Antonio its very popular. A lot of 900 repeaters are hooked up to echolink and such on private 900mhz only groups.

There is also a fair amount of commercial gear available for 900... I have a Motorola MCS2000, MTX 9250, and a Kenwood TK-981. Kenwood being the cheapest option if you can find one.
As far as TRBO goes, I have a XPR-4550 and a XPR-7550. You can pick up a XPR-6550/4550 fairly cheap now. Just have to look around. If you can swing the funds I recommend the 5550/7550. I think they have better audio and receivers.

As to the actual repeaters themselves, for TRBO (if you want on DCI or DMR-MARC) go with either an XPR-8400 (pass up the 8300 they have issues with heat on the PA) or a MTR-3000.
For 900 you can get Motorola Quantars or slap two mobiles together and get a old cell amp. Lots of options there.