San Francisco Public Safety going Digital June 2021

kg6nlw

Railroad & Ham Radio Extrodinare
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Can we please reserve this thread for updates on the SF P25 system? If you'd like to debate the merits of encryption, please start a new thread or join an existing one on that topic.

Agreed, but does that include showing what we get in DSD for encryption KeyID's? I think I remember a post about wanting those...?

Regards,

-Frank C.
 

kg6nlw

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OP25 Osmocom displays these. Not sure if Boatbod does.
I noticed and noticed DSD+ got an upgrade finally too...I just didn't know if that's something we wanted in the convo. I know it was *some* convo I saw that in, I thought it was the SF one hence why I asked.

Regards,

-Frank C.
 

rustyhodge

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Got a voicemail from someone who listens to the SomaFM scanner feed, irate at the quality since the switch to digital and also bemoaning the lack of police traffic... as if it was our fault :)

Here's a transcription
Hey listen I'm a guy who's always been listening to the scanner like since I don't know back in the seventies when I lived in Connecticut and you know I know things have certainly changed from the days when we had crystals that we would have custom designed and put in to radio scanners to today's 800 megahertz digital P. 25 front gated system but your scanner component on your channel it was like the best in the world for last 3 weeks it's going to complete **** there's absolutely there's almost no audio and when there is audio it's super garbled so I don't know what you guys have done here something went from being the best to the worst and it's a it's a service I really appreciate I really wish you guys should get a grip on that because it's just nice to be able to go back to the day of this news darned police truck traffic so please somebody take note of this and maybe make a phone call or whatever is needed talk to the person does the the engineering work on that I I don't know if they're using the new digital scrambling system or I who knows I mean I you know it nowadays the whole scanner things this way over my head so I got really depending on you guys to provide that service and I might add thank you very much for doing so okay thanks bye
 

KD6JEK

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Wow... I guess he hasn't been following the forum. What does he expect? You have no control over what is being broadcast. There is definitely less radio traffic with the encryption and the SFPD limiting the calls to Dispatch only, but that's not your fault or doing. Fire and EMS is still in the clear. As I say, it's still better than nothing at all so he should be happy with that, but I learned a long time ago that you can't please everyone.
 

anonymoose415

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Noticed the CHP Pink on TG 837 last night also, but at least at my location it was practically uncopiable since it was overmodulated/driven.
 

kg6nlw

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Just the other day CHP Emerald traffic (Santa Rosa) was being patched to TG 837 (SFPD MA2)

It was probably CHP GG-Violet as GG-Violet/GG-Emerald are patched together a lot lately, more often than not really.

Regards,

-Frank C.
 

footage

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I wonder if they are patching the Golden Gate Division rebroadcast from 453.825. This is conjecture as I'm not able to listen right now, but that would explain hearing several frequencies together.
 

kg6nlw

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I wonder if they are patching the Golden Gate Division rebroadcast from 453.825. This is conjecture as I'm not able to listen right now, but that would explain hearing several frequencies together.

Or they could be patching the 700 GG-Violet Simulcast (Golden Gate Bridge Simulcast) in...Less equipment needed as it's already 700.

Regards,

-Frank C.
 

kg6nlw

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I'm getting 453.850 on my old analog scanner. What's the difference between that and the 453.825?

UHF3 (453.825) and UHF4 (453.850) used to be CHP L8 and L9 respectively and they carry various office dispatch channels as backhauls to the low-band system.

Regards,

-Frank C.
 

rustyhodge

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Correct. We are only able to broadcast the unencrypted dispatch side. The amount of police traffic is a fraction of what it was. We countered by adding more EMS/Fire talkgrounds to the scanner feed.

In case anyone cares, the current scanner feed (which is a temporary setup) is a Bluetail P25RX feeding audio to an EQ and compressor/limiter plugins to more approximate the way the sound comes out the speakers on the radios. Mostly that's a 6db boost at 1.5-4k. That's going into Audio Hijack (on a Mac) to encode the stream. There is a perl script that grabs the last line of of the P25RX logfiles and feeds that to Audio Hijack's metadata encoder.

-rusty (SomaFM)
 
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