SFPD Low Band?

[W2MB]

I was recently visiting "the city" from the east coast and noticed that the majority of the SFPD patrol vehicles were equipped with two communication antennas. The one on the trunk lid was obviously for their trunked system, each car also and an old style spring loaded low band whip on the read fender. Does SFPD also uses low-band communication?

 

[Radiobern]

The low band frequencies are only used as a backup only. Regular communications are on the 800 MHz trunked system. After speaking with a couple of their dispatchers, they still refer to the dispatch talkgroup as the "low band" channel and the service talkgroup as the "pic" channel. The pic channel reference was a carryover from when they had 460 MHz UHF handhelds.

 

[W2MB]

Edit and Thanks

each car also and an old style spring loaded low band whip on the read fender should read:

each car also had an old style spring loaded low band whip on the rear fender

(I must have spend a bit to much time in the city)

It is interesting that the city would go thru the expense of installing old low band equipment just for backup purposes. One would think that it would propagate rather poorly in the city environment compared to higher frequencies. Is there any information on the low band frequencies that are used for this purpose?

 

[inigo88]

Here they are (taken from here):

45.10 (LOWBAND 1) DIVISION 2- RICHLAND, INGLESIDE, TARAVAL
45.14 (LOWBAND 2) DIVISION TWO- MISSION
45.58 (LOWBAND 3) DIVISION ONE- CENTRAL SOUTHERN TENDERLOIN
45.46 (LOWBAND 4) DIVISION ONE- NORTHERN PARK

They didn't spend any extra money equipping the patrol cars with lowband as backup. Prior to the late 90s, SFPD used these same lowband radios as their primary car radios (using those four non-repeated lowband channels), and 400 MHz portable radios called PICs. Essentially their cars were on one radio system while their portables were on a completely different radio system, so each division had a car channel and a portable PIC channel assigned to it.

When SFPD upgraded to their 800 MHz trunking system around 15 years ago, the vehicles and portables were upgraded with Motorola Spectra mobiles and XTS-series portables, both of which operate on the same radio system. However SFPD was so set in their tradition and way of doing things that they refused to allow the cars and portables to be on the same dispatch channel and continued to keep them on separate talkgroups. Taking Central Division (3Adam units) for example, every mobile radio is on PD-A1, but every portable radio is on PD-A2, and they may talk to two different dispatchers depending on which radio they use. Furthermore, they still call the 800 MHz mobile Spectra Radios "Lowbands", and the 800 MHz XTS portables "PICS" (after the 400 MHz system)... same reason, out of tradition, and training has never really changed.

The actual lowband radios are just kind of "there." My friend at the department told me there's no formal training on their use as a backup system, and he was under the impression they were there for mutual aid use with outside agencies. I tried my best to explain that actually, "this was your original lowband, before it got replaced with your new lowband... which isn't actually a lowband."

Also I hear the Motorcycle traffic division (company K) may occasionally use the lowband system. Their IDs differ from patrol because they start with a 4 instead of a 3.

 

[mrob907]

drives me crazy

The low band frequencies are only used as a backup only. Regular communications are on the 800 MHz trunked system. After speaking with a couple of their dispatchers, they still refer to the dispatch talkgroup as the "low band" channel and the service talkgroup as the "pic" channel. The pic channel reference was a carryover from when they had 460 MHz UHF handhelds.

And I am still trying to get people to stop referring to their 800MHz mobiles as "low band"
It's agrivating but you're right. and they do still refer to the handhelds as PIC, which was our
old acronym for Personal Instant Communications and dates to when handhelds were a "new thing"

 

[W2MB]

Very interesting way of doing things I must say, but then again, it's San Francisco. I wonder how much longer that they will be installing the real low band stuff in the cars. As crazy as it sounds, I have always felt it made sense to use simplex, point to point, non-trunked, non-digital, non-encrypted communications. The old timers say "there is no band like low band".

 

[mrob907]

absolutely

Very interesting way of doing things I must say, but then again, it's San Francisco. I wonder how much longer that they will be installing the real low band stuff in the cars. As crazy as it sounds, I have always felt it made sense to use simplex, point to point, non-trunked, non-digital, non-encrypted communications. The old timers say "there is no band like low band".

And on a nice sunny summer day, back in the early nineties (and probably 80's), you could go to the top of twin peaks and transmit via lowband and talk to a PD in Louisiana. I can't remember if it was Shreveport or where it was, but I have heard the older guys in the Department talk about that.

Lowband we use now only as back-up comms, some car to car, etc. We aren't spending any more money on the infrastructure, but we figure, the equipment still works, the Freqs are still licensed to us, may as well make SOME use of them.

 

[W2MB]

Back in the "day", well before I retired, we ran our comms on 39.24mHz. The portables, if you could call them that, would only work if you could see the station and when the band was open you could talk all over the place except to your own people. We still got the job done, probably even better than they do now days with all of the high technology.

 

[inigo88]

And I am still trying to get people to stop referring to their 800MHz mobiles as "low band"
It's agrivating but you're right. and they do still refer to the handhelds as PIC, which was our
old acronym for Personal Instant Communications and dates to when handhelds were a "new thing"

I'm glad to hear someone is trying to fight the good fight from within.

 

[zerg901]

It would be so easy to train people to use the low band radios.

900 AM - dispatcher says - "Car 1, turn on your low band radio and give us a test"

901 AM - 50 cars turn on their low band radios just to see whats going on

 

[rooivalk]

The coverage was better with the old PIC system. the trunked sysem has coverage problems, especially indoors and in the muni tunnels, and the dual trunked channel setup causes all sorts of feedback problems.

 

[Dann]

Is There Any Frequency And Use Updates On SFPD Low Band Radio System.

 

[kb6bf]

KMJ410
45.10 (2nd division: Mission, Ingleside, Taraval)
45.14 (Citywide)
45.58 (1st division: Potrero, Park, Northern)
45.46 (3rd division: Richmond)

 

[Dann]

Is There Much Use Of These Channels.

 

[inigo88]

Is There Much Use Of These Channels.

This question has already been answered (twice) earlier in this thread.

 

[Dann]

Ok, Sorry.

 

[nn6d]

SHOOTING FOR SURVIVAL, ca. 1960 - ca. 1969 - YouTube

check out this video on low band handheld use
- without extending the whip LOL LOL

 

[jvdet]

I just saw the low band whips while out there! and Mass has installed Low Band back in some cars also even though there use 800
But who still makes Low Band radios for public safety these days?

 

[BirkenVogt]

Kenwood still has the TK-6110 and TK-690 which are both great radios and have all the features of any other radio in any band except for trunking, of course. Even if they stopped making them tomorrow, they never break, and they will live on for decades especially with surplus stock on the market.