Erie County P25 System

Railbender

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It is the Rural sites you are not receiving. On a 536 lock out all but the County site and see what you receive.
 

scnrfrq

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It is the Rural sites you are not receiving. On a 536 lock out all but the County site and see what you receive.
I did try this before. I received nothing with the 536 set up that way. I think I also saw on the 200 that I was getting Emergycare on the Countywide site sometimes.
 

maus92

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Yes the TAC talkgroups are only carries on the associated sites. Reception of the Rural sites is very poor in his area. I have been in that area and checked. Even my Unication G3 was at 3 of 4 bars. In spite of what you may think there only TWO sites providing that signal in his area. I have plotted the radiation pattern for all of the surrounding sites. A cheap Yagi would probably help the 536s and the SDS200.
There are two (logical) sites (aka Cell) in this system: the Countywide (Simulcast) Cell, and the Urban (Simulcast) Cell - I don't think that I've ever expressed otherwise. I'm not sure what you mean by Rural sites. I do understand that SF's reception of the Countywide Cell is predictably marginal because his location is on the fringe coverage contours of several tower sites of Countywide Cell. The good news is that a radio designed to receive the signaling produced by this system (the SDS200) can reliably receive the Countywide site using a set-back antenna, and he can now decode and listen to Countywide TACs - something he was unable to do previously with his 536. I'm curious if SF still has the pronounced garbling of other TGs carried on the Urban cell when using the SDS200. He may have to experiment with different filtering options on the SDS to dial in optimum reception quality - something I do not have with our SDS200s.

A cheap Yagi could potentially help with the Countywide Cell if it could be oriented properly, but it was my understanding that he already tried this approach - maybe not. Similarly, a second Yagi could help with the reception of the Urban Cell in much the same manner, but is probably a bit clumsy. At any rate, it seems unnecessary now.
 
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scnrfrq

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There are two (logical) sites (aka Cell) in this system: the Countywide (Simulcast) Cell, and the Urban (Simulcast) Cell - I don't think that I've ever expressed otherwise. I'm not sure what you mean by Rural sites. I do understand that SF's reception of the Countywide Cell is predictably marginal because his location is on the fringe coverage contours of several tower sites of Countywide Cell. The good news is that a radio designed to receive the signaling produced by this system (the SDS200) can reliably receive the Countywide site using a set-back antenna, and he can now decode and listen to Countywide TACs - something he was unable to do previously with his 536. I'm curious if SF still has the pronounced garbling of other TGs carried on the Urban cell when using the SDS200. He may have to experiment with different filtering options on the SDS to dial in optimum reception quality - something I do not have with our SDS200s.

A cheap Yagi could potentially help with the Countywide Cell if it could be oriented properly, but it was my understanding that he already tried this approach - maybe not. Similarly, a second Yagi could help with the reception of the Urban Cell in much the same manner, but is probably a bit clumsy. At any rate, it seems unnecessary now.
Thanks for all the interesting info. I do have some garbling with the urban cell on the 200, something I didn't really expect. It is better than the 536 though. I haven't tried the filter options yet - not sure what to set them at for a system like this. Can you suggest anything?

I've only tried various back of set antennas so far, except for a ChannelMaster Monitenna I have installed in my attic. Haven't tried this one with the 200 yet.
 

maus92

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Thanks for all the interesting info. I do have some garbling with the urban cell on the 200, something I didn't really expect. It is better than the 536 though. I haven't tried the filter options yet - not sure what to set them at for a system like this. Can you suggest anything?

I've only tried various back of set antennas so far, except for a ChannelMaster Monitenna I have installed in my attic. Haven't tried this one with the 200 yet.
I cannot suggest any particular filter setting because, one, I don't need them thus have no direct experience, and two, they are highly dependent on location - thus what works well for one user does not work well for another even when monitoring the same system.

"Garbling" can be caused by multipathing at the receiver, but can also be caused by a subscriber unit not being within effective range of a receive site. The first issue is addressed by the SDS200 receiver design which compensates for multiple signals being received at slightly different times as does an actual subscriber unit. The second issue can be caused by overall system design, or software configuration in the user radios. The Erie system utilizes numerous directional antennas, particularly in the northern part of the county, and relatively low power base station radios in some locations to limit interference into Canada and otherwise shape coverage. The EFJohnson implementation of P25 systems also spaces tower sites a bit farther apart than other vendors, which can be an issue for subscribers, particularly portables. In the case of the Millcreek area, there is an issue where radios affiliate with the Countywide Cell when they should be affiliating with the Urban Cell. A change in radio firmware and a setting to prefer one cell over another should address that. The point is when a subscriber unit is not within optimal range of a receive site, DAQ will suffer, and that's a reason for garbling (and there is nothing you can do about that.). Garbage in, garbage out.
 
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scnrfrq

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I found a good discussion on filters here:
 

maus92

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I found a good discussion on filters here:
That would be a good resource. Look at post #6 where Upman says that setting the filters will be a "trial and error" procedure, meaning what works for one person may not work for another. So get ready to dig in and learn the capabilities of your radio!
 

scnrfrq

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TG 401 active today. Doing testing in Northeast by Welch's. Said reception was not great. Anyone know what this is?
 

scnrfrq

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Yesterday there was a fire call in the east county, and units were switched to "Government Northeast". I didn't hear anything else. Anyone know what talkgroup this is?
 

scnrfrq

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Anyone else noticing poor reception lately of the whole system? Both my 536's are sometimes scanning past TG's or only picking up parts of transmissions. Seems like something changed in the past week or so. Leaves on trees??
 

Railbender

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I was just analyzing the Rural site and had 80% signal and 100% quality. Then suddenly signal dropped to 0% and then jumped up and down. That happened when the control channel changed. Now it is back to 80% & 100% with another control channel. The problem was with a CC of 453.750 Mhz. 453.175 & 453.650 are good.
 

maus92

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Anyone else noticing poor reception lately of the whole system? Both my 536's are sometimes scanning past TG's or only picking up parts of transmissions. Seems like something changed in the past week or so. Leaves on trees??
Maybe. Does it affect your SDS200 reception?
 

scnrfrq

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SDS does the best. But it seems something got worse. 536's did ok before - now it's just tolerable. I wonder how it is for users of the system?
 

maus92

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SDS does the best. But it seems something got worse. 536's did ok before - now it's just tolerable. I wonder how it is for users of the system?
It could be leaves, or they could be working on the system, changing antennas, etc. Maybe both. Or weather. Hard to tell. You'll have to continue monitoring to listen for changes / improvements.
 

N3KGD

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Can anyone confirm or deny if the analog paging frequencies are using DPL, and if so, identify the codes? Every once in a while it sounds like I can hear subaudible data resembling what could be DPL being transmitted during the dispatches.
 

scnrfrq

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