New Trunked System in SF Bay Area?

[b52hbuff]

I took my radio up to a 'Vista Point' on 280 in San Mateo and did a 900MHz CC search. I found some of the 'usual suspects'. I also found what I think may be a new system.

SysID: 4900
Freq: 939.4875

A frequency search shows that it is used by IBM:
http://www.radioreference.com/modules.php?name=RR&action=fcc&cs=WNQL419

 

[WayneH]

I'm willing to bet it won't be that much more interesting than the Intel system. Probably the reason no ones ever bothered.

-Wayne

 

[b52hbuff]

I'm willing to bet it won't be that much more interesting than the Intel system. Probably the reason no ones ever bothered.

-Wayne

I'll take that as a challenge.

But seriously, I am not sure it's IBM. If you follow the link, you'll see it's registered for GI, not a trunked type. I'm wondering if it is IBM or someone else?

 

[WayneH]

The FCC licensing doesn't seem to be too strict with the service type. Look at LegoLand California. Last I looked they were set for trunked but operating 900 conventional. The story goes, as I worked for the shop that installed their equipment, was they wanted to go trunked at a later date. This was long ago so it doesn't seem like it's happened.

Maybe Intel's license people goofed or they 'upgraded'.

-Wayne

 

[wolter]

I wonder how "new" this system is.

Did you find it with your 396T? You said that you logged the SysID as 4900. I recall Paul Opitz saying that he personally programmed in the SysIDs if known. Otherwise the ID would have been the generic "MOT System".

 

[b52hbuff]

I wonder how "new" this system is.

Did you find it with your 396T? You said that you logged the SysID as 4900. I recall Paul Opitz saying that he personally programmed in the SysIDs if known. Otherwise the ID would have been the generic "MOT System".

I logged it with a 396T. Not all the systems are in the radio.

 

[wolter]

I logged it with a 396T. Not all the systems are in the radio.

But this one is, or it would read "MOT System". Opitz called it "4900" because he didn't know who it actually belonged to.

 

[b52hbuff]

But this one is, or it would read "MOT System". Opitz called it "4900" because he didn't know who it actually belonged to.

Opitz didn't call it anything. If the system is identified, then the name comes up, if it doesn't then it comes up with the Sysid #. Plug frequency into a Pro-96 and you'll see the same thing.

 

[wolter]

If the system is identified, then the name comes up, if it doesn't then it comes up with the Sysid #.

Try 938.1625 and 938.225. A Sysid # doesn't come up, only "MOT System".

 

[b52hbuff]

Try 938.1625 and 938.225. A Sysid # doesn't come up, only "MOT System".

Ok, away on vacation, but when I get back I will.

So I think we should put on our 'engineer hats'. Just how do you think this 'Sysid' works??

I think it is a field sent in the control channel stream. All Opitz did was see which 'popular' SysIDs people had identified and put them in the radio. So if there is a SysID decoded by the radio that isn't in the 'known SysID table', the radio simply passes on the Sys ID onto the display.

I beleive the only reason that you're only seeing 'MOT System' is that the radio can decode enough of the CC to determine it is a MOT, but not well enough to decode the SysID. So how many bars are you getting?

 

[wolter]

So how many bars are you getting?

On the two I mentioned? Three to four. But have picked up Sysid numbers on systems with no bars.

 

[wolter]

But seriously, I am not sure it's IBM.

It probably is IBM. The same frequencies that are listed on its page in US > California > Santa Clara County > IBM Research and Development here in RR.com are actually registered to IBM with transmitters in southern San Jose.

http://wireless2.fcc.gov/UlsApp/UlsSearch/licenseFreqSum.jsp?licKey=1926755

 

[b52hbuff]

Try 938.1625 and 938.225. A Sysid # doesn't come up, only "MOT System".

Are these control channels?

 

[wolter]

Yes. MOT System wouldn't come up if they aren't.

 

[sjsteve]

i work for one of the ibm sites in south san jose. i believe it is a freq for the 2 ibm sites in south san jose and it used for security purposes. one is silicon valley lab on bailey road off highway 101 and the other is almaden research on harry road. hope that helps somewhat