How's the PSERN system sounding to everyone? It seems very noisy and distorted to me. I figured being digital it would sound a lot better. Maybe it's just my equipment/setup (usb dongles with sdrtrunk).
PSERN Sound Quality.. bad?
- Thread starter louisik1
- Start date
I can get great sounding PSERN, so it isn't the system.
If PSERN, which is P25 II sounds bad - it's one of 2 things, both basically involve signal strength / bit error.
Remember, with analog, as it gets weaker, the signal has more and more static until it's unreadable.
Because P25 II is digital, its basically a stream of ones and zeros being broadcast. As long as all the ones and zeros arrive and arrive in order, it sounds good. As the signal becomes weaker, you start to get that 'garbled' sound, which is basically the radio missing ones and zeros.
So.....
#1 - better antenna
#2 - too far away from the transmitter or possible you are using a nonSDS radio and you are experiencing simulcast multipath interference.
If PSERN, which is P25 II sounds bad - it's one of 2 things, both basically involve signal strength / bit error.
Remember, with analog, as it gets weaker, the signal has more and more static until it's unreadable.
Because P25 II is digital, its basically a stream of ones and zeros being broadcast. As long as all the ones and zeros arrive and arrive in order, it sounds good. As the signal becomes weaker, you start to get that 'garbled' sound, which is basically the radio missing ones and zeros.
So.....
#1 - better antenna
#2 - too far away from the transmitter or possible you are using a nonSDS radio and you are experiencing simulcast multipath interference.
Sorry, I don't know what 'SDS' radio means.
I believe my signal is strong. I have no problem locking on call and talk channels, the spectrums look good (to my untrained eye), Is there something I could show you to get a second opinion?
It sounds similar to automatic gain control, cranking everything up to distortion. Maybe my antenna signal is too strong? I use sdrtrunk to pick up the PSERN system. I just installed Unitrunker with an extra tuner and straight away I'm getting decode value of 100 solid and window of 0, solid (using a warp of 0.52).
You can hear the sdrtrunk feed at Seattle Police and Fire (PSERN) Live Audio Feed
Thanks for any suggestions.
I believe my signal is strong. I have no problem locking on call and talk channels, the spectrums look good (to my untrained eye), Is there something I could show you to get a second opinion?
It sounds similar to automatic gain control, cranking everything up to distortion. Maybe my antenna signal is too strong? I use sdrtrunk to pick up the PSERN system. I just installed Unitrunker with an extra tuner and straight away I'm getting decode value of 100 solid and window of 0, solid (using a warp of 0.52).
You can hear the sdrtrunk feed at Seattle Police and Fire (PSERN) Live Audio Feed
Thanks for any suggestions.
With simulcast distortion, it is not a simple matter of signal strength.
First:
"SD" in SDS stands for software defined.
The SDS-100 and why it is so revolutionary | Scanner Master Blog
They make an SDS-200 also...
Simulcast....
A simuilcast 'site' is actually multiple radio towers, all putting out the same control channels and channel grants. So, your radio can pick up multiple signals, all the same frequency, but one or more may have bounced off of a building, hill or something. (It's called multipath). Because it traveled a farther distance than a direct, 'line of sight' signal, it is very slightly delayed (even at the speed of light, it is delayed). Non-SDS radios can have a very hard time decoding this mix of direct and delayed signals of ones and zeros.
Along with SDS100s and SDS200s, I also use 'gangs' of RTL-SDRs (6 total - 3 on each of 2 sites, Seattle/Eastside and West King County) on a Stridsberg and SDR-Trunk (I recommend this program highly). So, I have been 'sniffing" PSERN since it's initial testing. So, I am very familiar with it - and how it sounds.
Note that with RF 'dongles' like the RTL-SDRs, it is essential to play with the settings and gain to optimize. Crank the gain up too high, your noise floor will blow away everything but very strong signals. Again, try SDR-Trunk. I think it not only decodes/sounds better, it's easier to see what you are doing when adjusting settings - especially gain.
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Yes... I am using sdr tuners and sdrtrunk, so I know the sd stands for software defined. I've always heard it referred to as SDR, never heard SDS before, which seems to apply to one specific Uniden scanner? Anyway..
Thanks
Thanks
dpm3
Member
Does anyone have a list of which departments are currently active on PSERN? I have monitored Seattle PD on PSERN (West & South sites) with good copy, but attempts (a few weeks ago) to monitor Federal WAY PD didn't produce any activity. A list of which departments are actually active on PSEREN (updated regularly) would be most helpful. Monitoring Federal Way on KCERS/Valleycom can be pretty frustrating due to extreme static and intermittent signal mutes.
Right now, it's mostly Seattle agencies (PD/fire/public works). As well as some King Co (jail ops and some interop), UW PD and Sound Transit/Metro.
I'm too far north to monitor the southern sites/Fed Way (assuming they affiliate to south sites only), but they probably have not transitioned to PSERN - yet. I've been watching and KCSO has not transitioned yet either...
Keep looking here also:
Deployment Waves
https://psern.org/wp-content/upload...ard_Project_Timeline-DAS_charts_5.24.2023.pdf
I'm too far north to monitor the southern sites/Fed Way (assuming they affiliate to south sites only), but they probably have not transitioned to PSERN - yet. I've been watching and KCSO has not transitioned yet either...
Keep looking here also:
Deployment Waves
https://psern.org/wp-content/upload...ard_Project_Timeline-DAS_charts_5.24.2023.pdf
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devicelab
Whacker Extraordinaire
It should have been done on RR's database but the admin drank some gogo juice and the PSERN listing TGID list gre out of control.
Yes, seeing it all populated at once vs just the deps that have transitioned was suprising, when I saw it all was done.
However, I do appreciate it all (KCERS/16) being there because it saved me alot of manual SDRTrunk alias list and 100/200 FL building.
I suppose the admin's logic was to just do it all now and get it over with.
I get affiliations from Seattle/Eastside and 3 Sisters for Seattle police and fire here in Olympia on a Uniden 436. Sometimes it's not available in the same monitoring location, the next time I try to listen in.
I'm tempted for a G4, but future system limitations may make it a boat anchor.
I'm tempted for a G4, but future system limitations may make it a boat anchor.
I recently drove to Sea-Tac and monitored both the old and new systems on an SDS-100. The new system sounded great to me. What a difference from the old, usually crackily, analog system.
They tested the heck out of it when getting it ready for prime time.
Took some time to build/tweak, but it is certainly an improvement for the agencies using it too.
Now, if only the DE stays away....
jeremym70
Member
Works great on WSDOT. other than the fact you can't lock it on a site. I have mine programmed to scan only single sites if I so choose. I program a zone or two with the primary sites in that region, plus an all sites channel position. Wish they would have built more simulcast system in some of the bigger metro areas, but they only have the single simulcast around Seattle area.
It would be nice if you could force it to scan another site manually or lock onto a site.
jeremym70
Member
I think the last of the 800 LTR finally shut off within the last month or so. I think they said they may have said some high sites still in that weren’t accessible a month ago or so, but they may have killed them by now.
i have heard some traffic in the Olympic region when I have driven through, but not a lot. Still a lot of simplex in use. 700 is pretty busy in Vancouver area, you just have to scan through at least 3-4 sites to get alot
Okay thanks
devicelab
Whacker Extraordinaire
The 700 meg P25 simplex channels can be busy in the wee hours too.
jeremym70
Member
Haven't caught any in SWR yet, but haven't looked too hard either. I usually catch them on the same old analog 800 simplex channels.
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