The radio system upgrade and interconnection efforts are still underway, and continue through next week. This afternoon, a hardware failure occurred while one portion of that upgrade was in progress, causing our system to operate with fewer frequencies than normal.
Once that occurred, and for approximately the next fifteen minutes, conversations on the BRICS trunked radio system, which normally have thirteen voice channels to accommodate them, were limited to four. Because the dispatch center console system was still down, there was no way for dispatchers to preempt radio users in the field to make an announcement. BRICS staff then made an announcement to all public safety dispatching talkgroups advising that radio users should restrict themselves to emergency-related radio traffic until further notice. Even with an emergency traffic restriction, the demand on the system almost constantly exceeded the number of available voice channels and, as a result, users received “busy signals”.
Since busy signals have been an extremely rare occurrence on the system (less than 10 out of several million transmissions per year), users aren’t very familiar with what the signal means or how to respond to it. It’s important when receiving the busy signal to wait for the radio to give you the chirp to proceed, and not to try again in the meantime. Each time the user re-keys before there is a channel available, the user will drop to the bottom of the queue.
By the end of that fifteen minute period, the problem had been diagnosed and the failed hardware was replaced. Users were advised that they could resume normal radio traffic.
This was an unusual occurrence that was brought on by two completely separate functions occurring at the same time, and will probably never occur in the same way again. However, with the upgrade process continuing, all users should closely follow instructions and be cognizant that other issues may arise.