Montgomery County PSSM Program update

maus92

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OK, so tomorrow's the day for the police to migrate - has anyone set up their streaming rig for the new system?
 

mocomdcitizen

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I've been quietly feeding both the P16 and P25 systems simultaneously to OpenMHz since about mid-January, as I was anticipating the switchover last month. So far, it's mostly accidental or test transmissions. Though the past few days, the radio shop and other TGs has been performing more tests.

TGs that haven't been identified yet, or I haven't gotten around to adding them to a TG list to identify them, will have just the TGID.

EDIT: the URL doesn't include all the TGs that have transmitted, just the ones that tend to be commonly used. Easy enough to add in the TGIDs to the end of the URL.

 
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motorcoachdoug

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Well its now 0519 and I wonder if they will switch over at 0600 or 0700?? After they switch over then its time to fire up the SDR and Unitrunker as well. Its going to be a very busy morning here and hopefully we can do the buildout of the system in a few days or after they make the complete switch over within the next 2 weeks. I wonder when the county government and local governments will do the switch over as well.
 

mocomdcitizen

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It looks like a few transmissions are being broadcast on 851.275MHz as well, which is not on the list of frequencies for the P25 system. I'm not sure if this is a holdover from the P16 or if this frequency will be re-used for the P25 later on. If so, I'll have to retune my SDR.

Code:
[2021-02-23 13:29:46.254340] (info) [mocomdps] TG: MCPD A1 Dist1 (6000) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:33:15.793707] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:35:42.056147] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
EDIT: I think it's the P25 feeder I've setup is picking up P16 transmissions, while the P16 feeder is properly receiving them. Well, it's the first day, so it'll take some time to shake things out between the two and full adoption of using the new system.

EDIT2: after more observation, it looks like sometimes there are double transmissions - the same transmission being broadcasted on both P16 and P25.
 
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maus92

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It looks like a few transmissions are being broadcast on 851.275MHz as well, which is not on the list of frequencies for the P25 system. I'm not sure if this is a holdover from the P16 or if this frequency will be re-used for the P25 later on. If so, I'll have to retune my SDR.

Code:
[2021-02-23 13:29:46.254340] (info) [mocomdps] TG: MCPD A1 Dist1 (6000) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:33:15.793707] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:35:42.056147] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
EDIT: I think it's the P25 feeder I've setup is picking up P16 transmissions, while the P16 feeder is properly receiving them. Well, it's the first day, so it'll take some time to shake things out between the two and full adoption of using the new system.

EDIT2: after more observation, it looks like sometimes there are double transmissions - the same transmission being broadcasted on both P16 and P25.
This would be something that could be seen on Unitrunker configured to to monitor both systems. I'm trying to get out to the county sometime today to check it out, but they'll probably fix this pretty fast if the error is on their side.
 

HarryWilly

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It looks like a few transmissions are being broadcast on 851.275MHz as well, which is not on the list of frequencies for the P25 system. I'm not sure if this is a holdover from the P16 or if this frequency will be re-used for the P25 later on. If so, I'll have to retune my SDR.

Code:
[2021-02-23 13:29:46.254340] (info) [mocomdps] TG: MCPD A1 Dist1 (6000) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:33:15.793707] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
[2021-02-23 13:35:42.056147] (info) [mocomdps] TG: MCPD A6 Dist6 (6025) Freq: 851.275000 MHz Not Recording: no source covering Freq
EDIT: I think it's the P25 feeder I've setup is picking up P16 transmissions, while the P16 feeder is properly receiving them. Well, it's the first day, so it'll take some time to shake things out between the two and full adoption of using the new system.

EDIT2: after more observation, it looks like sometimes there are double transmissions - the same transmission being broadcasted on both P16 and P25.
The P25 system should be reusing all the old frequencies. That was my issue - as the control channels flip, I am using the same set of dongles for both systems so I have to watch the CCs to move them in the config and restart. I noticed too much strange behavior if they shared the same CCs for both.
 

maus92

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The P25 system should be reusing all the old frequencies. That was my issue - as the control channels flip, I am using the same set of dongles for both systems so I have to watch the CCs to move them in the config and restart. I noticed too much strange behavior if they shared the same CCs for both.
The P25 system is not going to use all of the SmartZone system frequencies. It will have a total of 13 channels, so some will not be reused in the TRS. And the SmartZone system will still be in use until all users move over by early March. Control channel management in the interim needs to be watched carefully.
 
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IQ_imbalance

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What's the protocol here...any benefit to posting TGIDs as they pop up? I've got the SDS200 running in discovery mode against the previous control channels....

Asking because probably 99% of the people on this thread know more about this than I do!
 

mocomdcitizen

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Thanks @maus92 and @HarryWilly!

With more channels coming into the mix, instead of the current 6 channels listed in the RRDB, I'll wait until MCFRS is cutover to the P25, then change the config to switch between the two dongles I'm using. So, for the OpenMHz feed, it'll miss a few transmissions until I make the swap.

This is going to be a fun next few weeks! :)
 

viggendriver

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What control channel are you guys hitting? I'm trying 853.9375 and 853.6875 and getting nothing however I'm down in Tysons and might be too far South:(
 

dwlipp

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The P25 system is not going to use all of the SmartZone system frequencies. It will have a total of 13 channels, so some will not be reused in the TRS. And the SmartZone system will still be in use until all users move over by early March. Control channel management in the interim needs to be watched carefully.
This is not correct, once the transition is complete all 20 frequencies will be active on the new system. That is several weeks away.
 

mocomdcitizen

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What control channel are you guys hitting? I'm trying 853.9375 and 853.6875 and getting nothing however I'm down in Tysons and might be too far South:(
Mine is currently locked in on 853.6875, but it may retune to the other alternative CCs. It may also depend on your scanner's settings. With my Unication G5, it took me a while to figure why I wasn't receiving anything (or out of range) as I didn't set the RFFS/Site to 1/2 for P25. You could, also be just outside of the transmission range.

EDIT: Thinking further... isn't SmartZone a mixed analog/digital system? So going full digital (P25) may reduce the overall transmit/receive range outside the county in comparison to analog.
 
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