Global Database Administrator
- Dec 23, 2001
- Ann Arbor, Michigan
Fist of all, looking at the system information in the database, and the FCC's database, there are two separate simulcast sites consisting of 11 sub-sites that make up the system. 10 of these sub-sites have co-located 460 MHz and 850 MHz equipment for the two simulcasts used by law enforcement and fire & EMS, respectively. The 850 MHz fire & EMS simulcast has an 11th sub-site at a separate location.Hard to believe that the entire city's communications is totally dependent on one site. I don't suppose they ever have lightning in DC either?
Oh yes, I agree. Even if the system failed "properly" it would cause big problems. That is the one inherent problem in Motorola trunking systems that there is only the one central controller. However, there should be a backup at the same location in case the primary one fails, although it could be subject to the same conditions which could cause it to fail also.Not so fast.
If it is anything like some other P25 systems from that era that I'm familiar with, they have a centralized controller. I've seen a number of them "kick the bucket" and leave entire systems in "site trunking". And if you need 11 sites (or more) in a system due to geography or desire for portable coverage, you'll find yourself having to dispatch from local firehouse/precincts - it can be a REAL problem if you don't have a plan.
If it makes you feel good.For which we keep the old mower, which still runs, out in the shed in case the newer one doesn't want to start and is repaired.
????????If it makes you feel good.
You will find that;
1) The old mower, not unused for several years is too rusty to actually work
2) The blades were dull when you put it away, and with time and being moved around are probably worse now.
3) After several years of a power mower you are more likely to buy a new one before actually trying to cut the entire lawn with the push mower.
But, if it makes you feel good. keep it.
(Above analogy applies to radio systems also)
Most of the places that don't have enough work to require more than that level of communication haven't developed internet connections or even pony express yet, maybe thats why you don't hear it. Or perhaps they have been around long enough to have enough conventional infrastructure and frequency allocation to support their operations (NYC)?How often did you ever hear of a VHF or UHF system failing compared to a TRS?
Somebody should check the RR / FCC tower data. Both systems have 10 colocated sites. Also, the DCFD system could not be patched to anything while it was down. The users merely selected a different zone in the subscribers.The FD 800mhz system has five locations. FCC Callsign KNJA391 Details
The MPD 460mhz system has six locations FCC Callsign WPYM761 Details
Three of the locations have both.
The FD system was patched into the Montgomery Co system, but there were some issues with signal strength according to the radio techs I was listening to and they working on using the Arlington Co system, or Alexandria if necessary, to make it work better.