Los Altos PW Frequency...

[b52hbuff]

I was wondering if anyone had any information on the new Los Altos PW frequency? According to the RR.com database, they moved from 46.54/162.2Hz to 460.125/162.2Hz.
Santa Clara County, California (CA) Scanner Frequencies and Radio Frequency Reference
460.12500 WQJX242 RM 162.2 PL Los Altos PW Operations FM Public Works

At one point in time, the db had both listed. 46.54 wasn't a very chatty frequency. I thought I'd see if the rainy weather may provide an oppoertunity to log the new channel. I set my HP-1 up to record for a couple of hours today and didn't hear anything on either channel.

Has anyone else heard the new frequency?

 

[jland138]

Maybe I'm 5150, but don't you think it's odd that the base sites listed for this "public works frequency" are not only LA City Hall, but also PA City Hall, the PA Municipal Center, MV City Hall and ECH with a P25 Phase I C4FM Voice emissions designator?

 

[johndrake]

I have never heard any traffic on the new 460.125 frequency. The old 46.54 frequency has been silent for at least 5 months. I don’t know if it’s coincidental but Sunnyvale’s DPW and water pollution control plant frequencies have also been silent for months.

 

[b52hbuff]

I've tried to get a look at the various trucks. From what I've noticed, the longer antennas for the 46.54 frequency have been removed.

 

[ctucker]

They're carrying MotoTRBO Radios now. Anyone have any thoughts on how to scan those?

 

[jland138]

Digital speech decoder (dsd) handles mototrbo and works well on simple (i.e.non-"capacity plus" systems). You'll need a radio with a discriminator tap and a computer with a sound card running linux to use it.

As I said in an earlier post, I don't think 460.125 is actually LAPW. I think it's going to be the new NORCOM channel for PA, MV and LA PD. But, I've been wrong before.

 

[jland138]

nortac

There was some testing on this frequency yesterday afternoon. NFM with a 110.9 PL. PAPD techs calling LAPD using "NORTAC" as the channel designator. The signal was somewhat weak with mediocre audio.

Here's a link to some of the test: YouTube - NORTAC Radio Test (2011-06-02)

 

[wolter]

They're carrying MotoTRBO Radios now. Anyone have any thoughts on how to scan those?

Are you sure? I used to work there, and we almost never used the radio. Puzzling that they would spend so much money on a system that they would hardly ever use.

 

[trooperdude]

As I said in an earlier post, I don't think 460.125 is actually LAPW. I think it's going to be the new NORCOM channel for PA, MV and LA PD. But, I've been wrong before.

Strong internal guidance that this will end up being a Law tac channel. Just waiting for some outside confirmation before changing the database to reflect it.

 

[b52hbuff]

Strong internal guidance that this will end up being a Law tac channel. Just waiting for some outside confirmation before changing the database to reflect it.

Thanks for the expertise... Any guidance on what is happening with Los Altos Public Works? I think I saw someone with a Motorola HT that looked 'newish'. No time to sit in the PW yard with close call on.

 

[trooperdude]

Thanks for the expertise... Any guidance on what is happening with Los Altos Public Works? I think I saw someone with a Motorola HT that looked 'newish'. No time to sit in the PW yard with close call on.

Haven't pursued PW yet, but I heard MotoTrbo in the mix (NOT confirmed).

I'll post when I find something.definitive.

 

[b52hbuff]

I managed to get a closer look at the radio. It was one of these:
XPR 6550 Portable Two-Way Radio - Motorola Solutions USA

 

[inigo88]

That's a TRBO radio all right! Fortunately Los Altos doesn't have very many FCC licenses, which makes it easier to rule things out:

LOS ALTOS, CITY OF   	WPBQ434   	33.10000 
LOS ALTOS, CITY OF   	WNGU395   	37.08000
LOS ALTOS, CITY OF   	KLU345          46.54000    - DPW Old
LOS ALTOS, CITY OF   	WQJX242   	460.125/465.125  - New Law Tac
LOS ALTOS, CITY OF   	KGK702   	483.06250 - Police Dispatch
LOS ALTOS, CITY OF   	WCH724   	485.33750 - BAYMACS Input

That's all of them, so we can rule out a city maintained system and start looking at commercial radio system providers. But who provides MotoTRBO systems in the Bay Area? These guys do:

Fisher Wireless - TeamTalk Network, LLC

The TeamTalk network is a UHF 450-470 MHz LTR PassPort system covering parts of California, Nevada and Arizona. However they've since deployed a MotoTRBO "Connect Plus" networked trunking system as well called "TeamTalk Connect", covering much of the same footprint. Here's the coverage map. The full system is on the last page.

From that coverage map, it looks an awful lot like there's a site on Loma Prieta, which would cover Los Altos. The following license has some potential freqs for the Loma site between 460-464 MHz:

FCC Callsign WQEG312 Details

The connect plus control channel will sound very similar to a regular Motorola Smartzone 3600 control channel, but will not decode. The TDMA trbo voice sounds like an intense buzzsaw type noise. It couldn't hurt to write down all the mototrbo freqs you can receive between 450-470 MHz (I know that's a LOT), and crosscheck those with the Fisher licenses for Santa Clara County, keeping an eye out for anything that sounds like a control channel. I'll bet that's where they went!

(Eventual verification with DSD will tell you for sure!)

 

[jland138]

Most likely, they're using CMMC's MOTOTRBO system on Black Mountain.
See the text at this link: About Metro Mobile Metro Mobile Communications Two-Way Radio Systems and Public Safety Equipment in the San Francisco Bay Area
CMMC mentions LAPW by name.

 

[inigo88]

Great find! This is the firstive heard of Metro Mobile.

http://www.metromobile.com/mototrbo/index.htm

Looks like their Black Mountain and Grizzly sites are "Capacity Plus" trunking, which is pretty well documented over in the digital decoding software sub-forum and is supported by the program "DMRDecode."

I couldn't find any "Metro Mobile" licenses so they must use a different company name on them.

 

[WayneH]

Telepath has TRBO stuff out there also. I seem to recall them with a UHF box on Loma Prieta.

 

[inigo88]

Doesn't surprise me. Sadly here in SD the TRBO trunking variants are taking over 450-470 MHz.