DMR ?

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headlinemen52

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Why is that i can hear simulcast channels from smith county but no receive DMR channels from smith county? I have SDS100 and DMR upgrade
 

ka3jjz

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It's virtually impossible to diagnose this without information. Just because you have the DMR upgrade doesn't really tell us much. Point to the database and tell us what you're trying to hear. Indoor or outdoor antenna? How high if outdoor and fed with what? How far are you from your targets?

It could be a programming issue - it's not as straightforward as you might think. What software are you using?

Too many questions, not enough answers...Mike
 

headlinemen52

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It's virtually impossible to diagnose this without information. Just because you have the DMR upgrade doesn't really tell us much. Point to the database and tell us what you're trying to hear. Indoor or outdoor antenna? How high if outdoor and fed with what? How far are you from your targets?

It could be a programming issue - it's not as straightforward as you might think. What software are you using?

Too many questions, not enough answers...Mike
Hello in door antenna software using ARC536 BASIC
 

hiegtx

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antenna is remtronix 820s christus trinity mother frances
This system?

The range in the database (which is only an estimate, based on what is licensed) is shown as 5 miles. But the antenna you are using, indoors, Remtronix 820S, is optimized for 700/800MHz systems, which is what the TxWARN sites in Smith County use. While the 820 does work reasonably well on Uhf, that's not it's strongest point. (The Mother Frances system uses Uhf.) On Vhf-high, it's a poor choice unless you are fairly close. or the system is unusually strong.

Does your house have aluminum siding, or foil backed insulation in the walls? If so, those also will negatively impact your reception of more distant transmitters. There are several Uhf DMR systems in use here in Dallas County. While I can receive them from home, at 30 miles I lose almost all of them. The only one with reliably longer range is the Megahertz system, which has several sites, including some at much greater height than would normally be found on a system, used by a hospital, which is mainly configured to cover the campus area, and it's immediately surrounding area.
 

ka3jjz

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Now assuming that we have solved the antenna issue, did you program the frequencies in LCN order, which I believe is needed for a Cap plus system? Look at the little numbers next to the frequencies - those are the Logical Channel Numbers (LCN)

It could be like Steve's discussion where it's a very low power system and you would need to be pretty close to hear them. That would make perfect sense in this case. Take your 100 to a spot that's close and see if you hear them. If you do, you've identified the antenna issue and found that the power is pretty low.

Mike
 

ka3jjz

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Looking at the RR map, there are quite a number of buildings in that area. UHF is very much line of sight- if your home is in line with any of those buildings and are between you and that hospital system, you can pretty much forget about hearing them, unless their antenna is physically higher than any of the others...Mike
 

RMason

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In addition to what has been suggested, make sure you have the appropriate Service Types enabled. The Christus Trinity Mother Frances DMR system uses Security, Business, and Emergency Ops. These are not enabled by default.
Mother Frances Hospital (Tyler) Talkgroups
NextLevel.gif


DECMode Alpha TagDescriptionTag
101TMFH SecuritySecuritySecurity
102TMFH EMEmergency ManagementEmergency Ops
103TMFH ParkingParking BoothsBusiness
104TMFH ShuttlesParking ShuttlesBusiness
 

hiegtx

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Just to add slightly to RMason's post, there's only four identified talkgroups listed for that system. Knowing how some of the DFW area hospitals operate, and how their systems are used, I suspect that there are more talkgroups than just the ones listed. The hospital is listed as having 400+ beds, so that's not a tiny one. Even if you used an external (rooftop) antenna, there's no guarantee that you could hear that system. If, at some point, you can receive it, then use ID Search to look for additional talkgroups. Do make sure that you have the correct service types enabled.
 

ke5fgc

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The antenna for that system is not up very high. It's mounted to the Radio Hut on top of Houston Tower and not actually on the antenna tower. The system doesn't have wide coverage.

As far as talkgroup usage the only talk groups that are regularly active are 101 and 104. Transportation still has an analog repeater but they don't use it much anymore as they have moved to smartphones.

When the system was originally installed the idea was that each of the local Christus facilities that had an armed security officer would be connected in. As far as I know, only one site is actually put on the air.
 
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