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(April 30, 2022) NBAM Volunteers Support Ridge-to-Bridge Endurance Event with 350 Participants

Updated: Jul 26, 2022

The NBAM Mesh was successfully utilized in the April 30, 2022 Ridge to Bridge hike/bike/equestrian event with 350 participants, sponsored by the Bay Area Ridge Trail Council.

This event started in East Fort Baker at sea level near the

north tower of the Golden Gate Bridge. The longest route, a 25-mile hike out-and-back, crossed three 800-1,000’ ridges and two almost-sea level valleys.

Using two portable ridgetop mesh nodes as relay sectors, Rob Rowlands NZ6J successfully connected three stations to the mesh: start-finish, Tennessee Valley, and Muir Beach. Using portable nodes and laptop computers, operators at the two rest stops entered the participant numbers into a spreadsheet as they passed by. The event organizers were able, in real time, to understand exactly which participants had reached Muir Beach, the halfway turn-around point, and which had passed through Tennessee Valley on the way out and then again on the return.

The event organizers knew which participants had failed to check in at either of the stops and were able to organize a focused search for the two missing participants. The information transmitted by the mesh removed much repetitive traffic from the UHF and VHF voice frequencies and reserved those frequencies for priority and logistical traffic. The mesh operators added a third licensed ham to each rest stop—no operator, either at net control or at the remote stations, was expected to operate both the digital and voice frequencies.

The spreadsheet at net control was posted on large-screen monitor so that any interested family member could follow their participant’s progress on the course.

In advance of the event, Bob Salter AI6EE collaborated with Ridge Trail staff to populate a spreadsheet with drop-down cells to enable synchronized

and prompt data entry to record the participants’ progress. He utilized a mesh-friendly software spreadsheet: Synology NAS Diskstation 118.

One important piece of equipment enabled the quick setup and

takedown of the portable relay nodes: Rob’s e-bike.

Marin Amateur Radio Support Receives Grant for New Backup Emergency Communication Network in Marin and Sonoma Counties

MILL VALLEY, CA – April 20, 2022 – Today, the Marin Amateur Emcomm Support organization and the Marin Amateur Radio Society announced that they received a grant of $92,000 to install a microwave “mesh” network in Marin and Sonoma Counties from Amateur Radio Digital Communications. ARDC is a California-based foundation with ro

ots in amateur radio and the technology of internet communication.

MAES (Marin Amateur EmComm Support) is a nonprofit whose goals include supporting emergency communications and networking with other similar organizations to that end. MAES is the grant recipient and fiscal agent for NBAM.

The mesh network, utilizing microwave frequencies allocated to amateur radio, will provide an alternative to emergency communications on the internet should power outages or other events render the internet unusable. It is also intended to provide an important means of disaster communication with community-based organizations, such as food banks, in und

erserved and rural communities.

The Marin-Sonoma network, called NBAM (North Bay Area Mesh), is connected to the already-established BAM (Bay Area Mesh) which serves the emergenc

y operations centers of San Francisco, San Mateo and Alameda Counties. There is a parallel effort in Contra Costa County. The long-term objective is to provide a region-wide communications network, operated by ham radio volunteers, that will provide a robust backup to existing means of communication among the various Emergency Operations Centers used by police and fire agencies in each county.

“The importance of establishing alternative methods and modes of high-speed reliable communication between the North Bay Counties is more important now than ever before,” said Dan Ethen, Chief Radio Officer of the Sonoma County Department of Emergency Management.

The Bay Area mesh networks are part of AREDN, the international Amateur Radio Emergency Digital Network, with networks in every state and most European countries.

Using off-the-shelf low-power microwave antennas, NBAM will identify and install key nodes on hilltop locations up the US 101 corridor from the Golden Gate Bridge north to Healdsburg and beyond. On the coast, the nodes will provide service to

the rural communities from Muir Beach, past Bodega Bay, and up to The Sea Ranch. BAM will partner with — and provide equipment and training to — radio clubs in each of the two corridors to place, maintain and utilize the mesh network.

“Mesh networks like this are both a way to offer resilient communications during emergencies and a platform to further explore the development of mesh technology on the amateur radio bands,” said Kristen McIntyre, Pacific Division Director of the Amateur Radio Relay League, the national association for amateur radio.

BAM is working closely with the Sheriff’s Departments in both counties. The Marin Amateur Radio Society has been an active nonprofit amateur radio Club since the 1930s with its own clubhouse (a retired fire station) in Mill Valley. Its FCC-licensed volunteers provide communications support to a dozen large-scale bicycle rides and footraces — includin

g the fabled Dipsea — each year. The society maintains a linked net of mountaintop repeaters enabling voice-radio access to and from all corners of the county. Those repeaters are used by the Sheriff’s Emergency Operations Center in times of disaster.

Rob Ireson, Chief Radio Officer, Marin County ACS-RACES , said “In a disaster, flexibility and redundancy are critical elements of resilience.”

“With BAM, we are upping our game to provide the best in supplementary digital communications for all licensed amateurs and emergency operations centers in both counties,” said Curtis Ardourel, President of the Marin Amateur Radio Society. “Communications support to the community is what we do, and we’re proud of it.”

Media Contact:

Michael Fischer



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