San Bernardino County System 4 and Ontario Mills Mall have the same System ID

[AM909]

In the database, San Bernardino County System 4 and Ontario Mills Mall both show a SID of 512C and connect tone of 105.88. I can hear the latter from Rancho Cucamonga, decoding the SID and connect tone, and confirm the traffic is mostly the patches of Ontario PD.

I can't likely hear the System 4 sites, which are in the Yucca Valley/29 Palms area, but I don't recall ever seeing two systems with the same SID and connect tone, especially not in the same area, so I'm guessing System 4 is the one that is wrong. I'll note that the two systems share four of their channels, probably without difficulty as their coverage areas likely do not overlap.

Can someone in the area of System 4 confirm?

 

[f40ph]

The Mall "fill-in" system was installed using the same setup as the 4-system. Users do not need a separate bank of channels in their radio. They are just told to switch to "4-FTAC-1" when in the area and they know that channel links them back to Ontario Fire dispatch. Same concept for Law. The TGs are in the database. Everything should be identical for both systems.

 

[AM909]

I went down to the Mills site to confirm that it is, indeed, what I'm hearing.

The channels are not exactly the same as the 29 Palms sites, though. The Mills site claims to use only 4 channels:

867.075
867.575 (control)
867.950 (control)
868.075

The license for that site (WQLJ857) has an additional channel, 866.950, but this is not in the channel list being broadcast by the system.

The license for the three 29 Palms-area sites (WPUT756) includes 866.950 also, but is missing 868.075. Additionally, it includes 868.1875, 868.3625, and 868.8375.

Also, the Mills talk groups are different. I've only heard 8336 and 8304, which the database says are patched to 9-OtoPD-1 (TG 4208 on system 9) and 9-OtoPD-4 (TG 4336 on system 9). All the talk groups for the Mills system in the database are described as patches to system 9, some of them with the same talk group, some not.

It seems that the Mills system is a fill-in for system 9, though I'm surprised it's necessary -- the Mt. Jurupa site looks to be 7 miles line-of-sight and at least 230 feet higher. It makes sense to re-use four of the channels from the 29 Palms system, which is reasonably likely to have no overlap in coverage at the 15 watts ERP level.