III. System Impact and Current Understanding
The incident identified a need for greater understanding among dispatch personnel and public safety agencies regarding the design and operation of the county's radio system.
Dispatchers do not necessarily have a complete understanding of the technical operation of the radio system. This is particularly true with respect to the distinction between the Sampson Tower site and the overall 800 MHz radio system.
VHF Paging
The county previously relied on the Sampson site for VHF paging. There was no active redundant VHF paging site in place when the Sampson site failed.
Over the past several years, VHF has gradually been phased out as fire departments have increasingly transitioned to the 800 MHz system. As a result, VHF capabilities have become increasingly limited.
VHF paging and toning remain out of service at this time. Equipment has been ordered and is expected to arrive early next week. Once the equipment is received, the intention is to restore VHF capability from the Delta Tower as a temporary solution.
Motorola has also been advised that, once the Sampson Tower is restored, the equipment installed at Delta should remain in place to provide a backup VHF capability.
800 MHz Radio System
The 800 MHz radio system did not go down during this incident.
The system continued to operate as designed by utilizing repeaters located at other tower sites. However, the loss of the Sampson site reduced coverage in certain areas, particularly for portable radios and, in some circumstances, mobile radios.
If a portable or mobile radio is outside the effective range of another operational tower, the radio may not be able to communicate. Portable radios are particularly susceptible to these coverage limitations.
A radio that previously worked inside a building while the Sampson site was operational may no longer work in that same location if it cannot establish a connection with another tower.