I'm somewhat still a newbie to SDR's and using both Unitrunker and SDRTrunk (my preference so far) having cut my teeth in successfully configuring systems in another state and one on Long island. In fact, the one out of state system was a very complex system encompassing 9 counties and a tremendous amount of talkgroups but sites that were more defined to specific geographic areas. Trying to set-up Suffolk County using 2 SDR's and so far am not getting anything so I'm apparently doing something different than the other 2 P25 systems I've done. I understand that Suffolk County has both 700 and 800 Mhz systems in the same system and it might be best having one dongle configured for the control channels and one for the audio traffic or the systems segregated to individual dongles. Issue is that there are 7 sites listed, some with only control channels so I'm not sure which ones I should populate the frequency lists with. I've populated the aliases using Radio Reference. I'm interested in only the eastern end of the county, i.e. not the west simulcast site radio traffic which is way too much information to listen to. What control channels and protocol should I be using? I've tried p25 phase 1 and 2 FDMA and TDMA. Or maybe I'm just in a bad reception area as the control channels keep showing Idle yet I do get some reception using my BCD436HP. Thanks for any recommendations.
2 SDR SDRTrunk system setup for Suffolk County P25
- Thread starter golsonnj
- Start date
Suffolk County is designated as a P25 Phase II site, so setup accordingly, but it uses a mixture of Phase I and Phase II.
It appears that you would need 3 dongles. 1 for 800 simulcast control channels, 1 left open, no channels defined, SDRTrunk will use to cover the 800 simulcast frequency range efficiently, and 1 for the 700 simulcast system. Both systems can use the same Alias list.
I doubt you need the other towers setup, as I did not have to set them up for the fellow on the east of the island when I programmed his scanner.
It also depends on your antenna, outside antenna is better than the inside piece of junk that comes with sdr's.
It appears that you would need 3 dongles. 1 for 800 simulcast control channels, 1 left open, no channels defined, SDRTrunk will use to cover the 800 simulcast frequency range efficiently, and 1 for the 700 simulcast system. Both systems can use the same Alias list.
I doubt you need the other towers setup, as I did not have to set them up for the fellow on the east of the island when I programmed his scanner.
It also depends on your antenna, outside antenna is better than the inside piece of junk that comes with sdr's.
This will depend on what you want to monitor. If you are interested in FD comms, you'll need the 700 Simulcast layer. All other activity on the TRS is on the 800 Simulcast layer.
You also said you wanted East End traffic. If you are interested in truly listening to the east end, which would be the Hamptons, you'll want to monitor the East Hampton P25 system.
UniTrunker won't monitor PII talk groups, only P1. That may be part of your issue. Setup SDRTrunk with LSM and you should have no issues picking up voice traffic, assuming you can hear the control channels on the layer you want to monitor.
You also said you wanted East End traffic. If you are interested in truly listening to the east end, which would be the Hamptons, you'll want to monitor the East Hampton P25 system.
UniTrunker won't monitor PII talk groups, only P1. That may be part of your issue. Setup SDRTrunk with LSM and you should have no issues picking up voice traffic, assuming you can hear the control channels on the layer you want to monitor.
Thanks for the recommendations. I'm still working through the Suffolk County set-up so far using only 2 dongles but may opt to go with 3. Mostly interested in Fire and EMS traffic so might opt for only one of the systems. Bigger problem I've now encountered is on the East Hampton Public Safety (P25) system that I had working fine but am finding that because it is linked to the Suffolk County system, a lot of 65nn talkgroup traffic is being received. I'd like to filter that out out but haven't figured out how to do it yet.
Thanks. Yes, I am using SDRTrunk mostly because of personal preference but recall the Phase 2 issue being mentioned somewhere. First set-up the East Hampton Public Safety (P25) system for Fire, EMS and police. EH is configured as a Phase 1 protocol which I configured as 2 separate playlist sites - 700 Simulcast and 800 Simulcast. Seems to be working well except because the Suffolk County and East Hampton systems are somehow linked, I'm getting a lot of 65nnn numbered talkgroup traffic coming over from the Suffolk County system. Also not seeing any activity on the 800 Simulcast site so not sure if something is wrong with my set-up. Keeps indicating Idle. I'd like to filter the 65nnn's out but haven't figured out how to yet. Am using an alias list that I've edited to mute EH talkgroups that I'm not listening to but the linked 65nnn ones aren't in the playlist to mute.
You have to have the 65nn channels in the Alias list, and then mute them or add them to a Blacklist. Other wise they will show up and possibly play the audio.
If using inside antenna, move the antenna around and see if you pick up the 800 system, if it keeps showing idle it is not picking up the 800 system, you need an outside antenna.
The system is 2 layers and Fire and Ems are on both layers. You will need at least 2 dongles. 1 for 700 and 1 for 800 if monitoring the East End sites.
As far as SDRTrunk goes, it gets programmed as one system, programmed as P25 Phase 1, with one playlist containing all of the systems tg's. Then just program the sites of interest. Associate each site to the one playlist. Lock out all unwanted tgs.
If you just want the East End, then you should be able to get (based on freqs listed in db now) going with 2 dongles. One on 700 and one on 800.
| 1 (1) | 008 (8) | Montauk (1.9125 MHz) | 851.3875c | 851.600c | 852.600c | 853.300c | ||||
| 1 (1) | 009 (9) | 700 East Simulcast (1.875 MHz) | 772.29375c | 772.90625c | 773.66875c | 774.16875c |
Site 9 - Select control and alternates
Site 8 - It will only allow you to select control as there are no defined alternates. (all other sites have defined alternate control channels)
If site 8 is not working, then you would need site 4 (control and alternates) which would require 2 dongles just for that site alone as that site spans 2.7625 MHz.
Set up a tg range alias (lowest unwanted tg to 65535) (and name it patch block) and set it's listen and record to off.
There may be more dynamic tg's showing on the system, possibly in the 65xxx range. Suffolk and CLERM (CT) will be linking via ISSI in the near future.
Thanks everyone. I've somewhat put the Suffolk County P25 programming on the backburner for the moment because it doesn't seem to offer much in the way of east end radio traffic, i.e., East Hampton, Sag Harbor and all the villages out towards Montauk are on the East Hampton Public Safety (P25) system. With that, I went back to try optimizing the East Hampton Public Safety (P25) setup and created a muted alias for 65000-65535 which has silenced the patches from the Suffolk County P25 system. But with both the 700 and 800 Simulcast sites configured for East Hampton in SDRTrunk, I'm not seeing any activity on the 800 Simulcast site not even anything on the control channels as if the site is dead. At the same time, I was encountering some missing traffic on the 700 Simulcast site based on listening to my BCD436HP. So I disabled the 800 Simulcast site and SDRTrunk is now using both dongles for the 700 Simulcast and I am no longer missing traffic and in-fact am picking up things that my BCD436HP was missing on account of how much it is trying to scan. I don't think it's an antenna issue as I'm not having any problems with the 700 MHz frequencies which now seem to reflect a roughly 771 MHz control and 774 MHz audio traffic. I'm thinking the frequency spread was just too much for a single dongle. But I'm at a loss as to what's going on with the 800 MHz site or is it just not being utilized. The 800 MHz sites seem to be somewhat co-located near or where the 700 MHz sites are so adequate reception wouldn't seem to be the isssue. I also see where EH fire has some 800 MHz conventional frequencies and still pages over 453.425 MHz. Guess I may be needing additional SDR's due to the bandwidth involved. I cut my teeth programming my 2 SDR system using the very large 9 county SEGARRN system in GA which for the county I'm interested in there with 2 dongles handling things very well with little to no lost transmissions. Up here, things still seem to be a mix of VHF, UHF, and conventional and trunked 700/800.
For East Hampton 800, your not going to cover that site and 700 with just 2 dongles.
Chances are your using what SDRT imported from the database which would just be the 2 freqs marked as control channels.
To see if the 800 site is active, try scanning the 2 freqs not listed as c and also this one, 859.7625 that's not in the database. Im sure one of the three may be an active control channel.
| 855.2125 | 856.0875c | 858.7625c | 859.9375 |
Chances are your using what SDRT imported from the database which would just be the 2 freqs marked as control channels.
To see if the 800 site is active, try scanning the 2 freqs not listed as c and also this one, 859.7625 that's not in the database. Im sure one of the three may be an active control channel.
Thanks for the suggestion. I had already tried that including the 5th frequency not reported in RRDB that I came to find through an FCC ULS search. I'll review again just to make sure I didn't miss something.
Just an update that I turned off the 700 Simulcast channel and configured the 800 Simulcast with all 5 frequencies and let SDRTrunk play using both dongles. All 5 frequencies are scanning through but show Idle and nothing on the waterfall. I don't think I'm doing anything drastically different from the 700 Simulcast which is working fine. I wouldn't think coverage should be an issue where I am at but I'll explore moving my antenna to a better location.
If you have a scanner try programming the 5 in that and take a drive closer to the site. Or if your using a laptop take that closer.
I think it may actually be that I'm not close enough to any 800 Simulcast site. They have 6 sites licensed for the 700 Simulcast and 5 sites for the 800 Simulcast with most co-located or real close to each other except for one 700 MHz site that doesn't seem to have a licensed site associated with it and that I am probably much closer to than any of the other 800's. I have to see if I can get better antenna coverage or somehow figure out how to take the show on the road to see what happens when closer to one of the licensed 800 sites.
