The Department of Defense will host this year’s Armed Forces Day (AFD) Crossband Test, scheduled for May 10, 2025. This annual event is open to all licensed amateur radio operators and will not impact any public or private communications. For more than 50 years, military and amateur stations have taken part in this event, which is an interoperability exercise between hobbyist and government radio stations.

The AFD Crossband Test is a unique opportunity to test two-way communications between military communicators and radio stations in the Amateur Radio Service (ARS), as authorized in 47 CFR 97.111. These tests provide opportunities and challenges for radio operators to demonstrate individual technical skills in a tightly controlled exercise scenario that does not impact any public or private communications. ¹

ℹ️ The complete event schedule is available for download from the DoD MARS COMEX information website.

Celebrate 75 years of US Air Force MARS operation with an Amateur Radio Special Event in the Technician and General portions of the 160–6 meter bands (excepting 60M) from November 5th 0001Z through November 11th 2359Z using SSB, CW, and digital modes.

This is a certificate only event; no QSLs will be exchanged.

Air Force MARS 75 Years Special Event Amateur Operator Instructions

Timeframe

5 Nov 2023 0000 Zulu to 11 Nov 2023 2359 Zulu

Frequencies

Only Amateur Radio frequencies in the General and Technician band privileges may be used in the 160–6 meter bands. Use of 60 meters is not authorized. Multiple Wings may operate in the same band up or down of event frequencies and bands.

Modes

Voice, CW and Digital Modes (commonly used such as FT8) will be used. Make sure to listen for the special event call signs

Spotting

Please spot your contact and use available spotting software to see where operators are.

Records

All contacts received by AFMARS Special Event Stations must be provided in ADIF format to the event collector daily. Any logging software capable of this format may be used. After November 30th the Amateurs will need to request a certificate.

A Mission Statement PDF Flyer for this event is available for download.

Example Exchanges

Voice

1. AFMARS Station: CQ CQ THIS IS W1B AIR FORCE MARS 75th SPECIAL EVENT SECOND WING CQ CQ
2. Amateur Station: W1AW
3. AFMARS Station: W1AW THIS IS W1B YOU ARE “5 by 9” OVER
4. Amateur Station: THIS IS W1AW YOU ARE “5 by 9” OVER
5. AFMARS Station: QSL INFO ON QRZ THANKS FOR THE CONTACT OUT

Digital

CW and Digital mode exchange format will contain the pertinent information.

Event Call Signs

About US Air Force Military Auxiliary Radio System (MARS)

MISSION

The United States Air Force Military Auxiliary Radio System provides contingency communications support on behalf of the men and women of the Department of Defense and other U.S. Government users in support of their important and diverse national security missions whenever, however and wherever required.

VISION

To support the Department of Defense and U.S. Government as tasked and within our capability by providing first-rate, on-demand contingency communications services that rival far more complex and expensive systems levels of service and quality, and to do so in peacetime or times of national crisis, on an around-the-clock basis, and at no expense to the US taxpayer. Members will use their own resources and contributed time to provide these services.

VALUES

We view our Air Force MARS service as a patriotic duty. We employ our God given talents and resources to meet our operational commitment. At all times we strive to provide communications encompassing the finest traditions of the United States Military and fully embrace the Air Force Core Values of Integrity First, Service Before Self and Excellence in All We Do. ¹

How to join MARS

• 📧 Send e-mail to join@afmars-mil.us
• ☎️ Call 888-778-6277

Would you like to know more?

• 🔗 AFMARS Public Home Page
• 📄 MARS Recruiting Flyer (PDF)
• 🔗 Military Auxiliary Radio System page (Wikipedia)

MARS Website

https://community.apan.org/wg/air-force-military-auxiliary-radio-system-afmars/

MARS Contact

join@afmars-mil.us

On April 29, 2022, ARRL News reported about a MARS HF skills exercise during early May 2022…

Members of the Military Auxiliary Radio System (MARS) will conduct an HF skills exercise from Monday night, May 2 through Saturday, May 7, 2022 to practice interoperability with the amateur radio community.

A 60-meter high-power broadcast will begin on May 3 at 0200 UTC followed by the FEMA region net. That will continue four more nights at 0200 UTC with the region net. At 1200 local each day (May 3–7; Eastern, Central, Mountain, and Pacific) the net will be called by region.

MARS members will be reaching out to the amateur radio community via the 60-meters Channel 1 Net (5330.5 kHz). These are directed nets. The nets will be run by region. These are not typical “everyone check into the net” operations. Amateur ops who participate should listen first. Net control will ask for stations meeting specific criteria to check in, e.g., stations in a particular geographic area. Only stations that meet the criteria should check into the net.

In addition to 60 meters, MARS stations will also reach out on amateur frequencies such as 80-meter traffic nets and other bands they may be able to reach. ¹

The DOD COMEX 22-2 Amateur/AUXCOMM interface document is available from ARRL.

The Army Military Auxiliary Radio System will host the 2022 Armed Forces Day (AFD) Crossband Test on May 14, 2022.

A list of participating stations, modes, frequencies, and times will be published April 1, 2022, on the DoD MARS - Armed Forces Day page

The AFD Cross-band Test is a unique opportunity to test two-way communications between military communicators and radio stations in the Amateur Radio Service, as authorized in 47 CFR 97.111. These tests provide opportunities and challenges for radio operators to demonstrate individual technical skills in a tightly controlled exercise scenario that does not impact any public or private communications."

Military stations in various locations will transmit on selected military frequencies and announce the specific ham band frequencies they are monitoring. ¹

MARS-Amateur Radio Interoperability Exercise to Test “Very Bad Day” Scenario: From October 30 through Novembe... https://t.co/0Dpnd1etc1

— ARRL (@arrl) October 19, 2016

An Amateur Radio-military interoperability exercise will take place October 31 and November 1. The event will begin at 1200 UTC on October 31 and continue through 2359 UTC on November 1 on 60 meter channels 1-4—5.3305 MHz, 5.3465 MHz, 5.357 MHz, and 5.3715 MHz, respectively.

During this exercise, military stations will attempt to make radio contact with stations in as many of the 3007 US counties as possible. Radio amateurs providing “county status” information will receive a US Department of Defense “interoperability QSL card.”

Contact the Military Auxiliary Radio Service (MARS) for more information.

(From: ARRL: Amateur Radio-Military Interoperability Exercise Set for October 31-November 1)