Calvert Amateur Radio Association Conducts Simulated Emergency Test

On October 15, 2022, the Calvert County Auxiliary Communications Services of Maryland, associated with the Calvert Amateur Radio Association (CARA), conducted a Simulated Emergency Test (SET).

The test was designed to evaluate the capability of a county-provided, amateur-band radio system that uses Kenwood TM-V71A transceivers and Remoterig RRC-1258 hardware over the county-secure intranet to a tower site in Barstow, Maryland.

Remoterig gear allows for the separation of the front panel from the radio's RF deck, similar to a mobile installation. But with Remoterig, the separation cable is a TCP/IP network, allowing an arbitrarily long distance between the front panel and the RF deck. For the SET, the radio's front panels were in the Emergency Operations Center (EOC), and the RF decks were at a tower site about 3 miles away, near the geographic center of the county.

The planning and implementation of this system was guided by Calvert RACES Officer Bill Hackett, N3XMZ, and Calvert ARES® Emergency Coordinator Shawn Donley, N3AE, using county funding.

The first part of the test was to determine if MT63-2000L digital mode would work over the Remoterig system to augment existing Winlink capability.

The second part of the test was to have CARA members transmit on simplex from mobile transceivers from various locations in the county to the Barstow tower. Transmissions from low-lying areas were preferred, such as the many waterways and other locations that may need to be accessed during disasters. The tests were on 2 meters and 70 centimeters.

The results showed that additional work is needed to send MT63-2000L over Remoterig terminals, and some changes to the audio quality settings are necessary (sampling rate and word size). As the Diamond X300NA antenna on the tower is 350 feet above the ground and the terrain of the county is flat, nearly all locations were successful in contacting the ham radio operators at the EOC, including those using low power at the tower site.

Due to unforeseen problems with scheduling a Section-wide October SET, CARA took the opportunity to evaluate its new system. Overall, the test was successful.