San Francisco Public Safety going Digital June 2021

officer_415

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As usual lots of activity on the 1400 series as well, all ENC. From the density of transmissions on the 1400 series I am hypothesizing that these are DPT, which might well be encrypted because of the large amount of PII that is passed over these TGs. I have not heard DPT units on other unencrypted TGs.

DPT (SFMTA) is still operating normally on the old system. I don't see any corresponding traffic on the 1400 series talkgroups.
 

footage

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There's a increasing number of low-numbered TGs on the system, all encrypted. Some might correspond to low-numbered TGs on the old system used by SFPD, but I am doubtful all are used by SFPD. Does anyone have any insight? Numbers seen, many in recent days, are 1, 6, 12, 14, 16, 18, 20, 26, 27, 28, 32, 34, 35, 36, 38, 39, 40, 46, 48, 59, 61, 63, 67, 69, 73, 77, 79, 108, and 111. And new TGs in this range show up every day.

In addition, TG 60102, used from time to time for automated SFFD dispatches, now seems to be encrypted.
 

officer_415

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59 and 61 should be SFFD B13/B14 for medic-to-hospital communications, but I have not confirmed this. I haven't seen any activity on these talkgroups, or 944/976 on the old system.

63 should be SFFD Arson (B7 on the old system, E7 on the new system). I suspect most of the others are probably SFPD specialized units.
 

rustyhodge

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Where are the repeater sites in SF for the new digital system? I assume one is on Twin Peaks, the other on Candlestick hill / Bayview Park? I'm wondering if a Yagi will improve the multicast issues I often get. Candlestick is about 90 degrees off from my shot to Twin Peaks.
 

scannerboy02

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Where are the repeater sites in SF for the new digital system? I assume one is on Twin Peaks, the other on Candlestick hill / Bayview Park? I'm wondering if a Yagi will improve the multicast issues I often get. Candlestick is about 90 degrees off from my shot to Twin Peaks.
 

rustyhodge

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Thanks, not sure where I saw the reference to the site on Candlestick point. Per your link, these are the main stations:

"Trunked Public Safety 700 MHz License - WQOA369"
99 MOULTRIE ST - Bernal Hill
CHRISTMAS TREE POINT TWIN PEAKS BLVD - Twin Peaks
181 MENDOSA AVENUE - Forest Hill
ONE MARKET PLAZA - Across from Ferry Building
57 ALTA VISTA WAY DALY CITY, CA - North edge of San Bruno

I guess my real question is, are these all active?
 

rustyhodge

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I'm a bit confused about multicast vs simulcast. This link says Multicast sends the same info on different frequencies, rather than on the same frequencies. If some scanners do better or worse quality with multicast, why is that? I could understand if it was simulcast. Or is it that the scanner is not picking the strongest signal and hence the bad audio is because you're not decoding the strongest signal?

 

officer_415

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Where are the repeater sites in SF for the new digital system?


I'm a bit confused about multicast vs simulcast. This link says Multicast sends the same info on different frequencies, rather than on the same frequencies. If some scanners do better or worse quality with multicast, why is that? I could understand if it was simulcast. Or is it that the scanner is not picking the strongest signal and hence the bad audio is because you're not decoding the strongest signal?

Multicast is the same traffic going out on multiple sites, each with its own frequency. Scanners don't have a problem with this, because they are only receiving one site at a time.

Simulcast is the same traffic going out on multiple sites, all using the same frequency. This is commonly used on P25 systems, and requires very precise synchronization of all the sites. Scanners sometimes have a problem with this, because they are receiving the same signal from multiple sites and can't decide which one to decode.

Pointing a Yagi at one of the sites, or physically positioning yourself close to it, helps the scanner receive a stronger signal from just that site. This usually results in better decoding and cleaner audio.
 

WB6WQF

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Multicast is the same traffic going out on multiple sites, each with its own frequency. Scanners don't have a problem with this, because they are only receiving one site at a time.

Simulcast is the same traffic going out on multiple sites, all using the same frequency. This is commonly used on P25 systems, and requires very precise synchronization of all the sites. Scanners sometimes have a problem with this, because they are receiving the same signal from multiple sites and can't decide which one to decode.

Pointing a Yagi at one of the sites, or physically positioning yourself close to it, helps the scanner receive a stronger signal from just that site. This usually results in better decoding and cleaner audio.

“Glay Jones” should be “Clay Jones”.
 

kg6nlw

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“Glay Jones” should be “Clay Jones”.
Yeah us locals know that but tell that to the following as they're the ones that submitted the FCC Data like that! :LOL: :rolleyes:

City and County of San Francisco
SHOME VASUDEVAN
200 PAUL AVE, BUILDING B
SAN FRANCISCO, CA 94124


Regards,

-Frank C.
 

kg6nlw

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Some talkgroups I saw today while "scanning" around that don't have any RRDB entries...Maybe someone can take a look at these who lives closer?

P25, BEE00.2BB, 38
P25, BEE00.2BB, 54
P25, BEE00.2BB, 831
P25, BEE00.2BB, 879
P25, BEE00.2BB, 1078
P25, BEE00.2BB, 1403
P25, BEE00.2BB, 1404
P25, BEE00.2BB, 1405
P25, BEE00.2BB, 1417
P25, BEE00.2BB, 1419
P25, BEE00.2BB, 1420
P25, BEE00.2BB, 6003
P25, BEE00.2BB, 35120
P25, BEE00.2BB, 35124
P25, BEE00.2BB, 35126

Regards,

-Frank C.
 

footage

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Late this morning, about 11. Just a few routine police xmsns. Was working so didn't catch the content but heard dispatcher and saw TG on screen.
 

footage

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SFPD A2 (TG 805) in unencrypted mode now. Probably still testing because it's transmitting more than just dispatches and dispositions (although the rumor that that's all we were going to hear may be incorrect).
 
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