Performing the Ameritron AL-811 MARS Mod is simple with a little knowledge and basic tools. The AL811 amplifier is limited to traditional ham radio bands before the modification.
For those involved in the Military Auxiliary Radio System (MARS) or who want or need to operate on 10 & 12 meters, as well as frequencies outside standard amateur bands.
Why You Need the MARS Mod
The MARS mod expands the frequency range of the AL-811, and AL-811H enabling transmission on 2 ham bands, and including frequencies not typically allowed under standard amateur licensing.
This is particularly useful for MARS members who support emergency communication efforts by providing backup communication channels for the U.S. Department of Defense. Additionally, radio operators involved in disaster response or those who hold special permits may also benefit from this mod.
What the MARS Mod Does
When you perform the MARS mod, you effectively remove the factory-imposed restrictions on the AL-811. As a result, the amplifier can now transmit across a broader spectrum, including MARS and other authorized frequencies.
Importantly, this modification does not increase the output power of the amplifier; instead, it simply unlocks additional frequency ranges. Therefore, operators must still adhere to all licensing and regulatory requirements when using the expanded capabilities.
What the MARS Mod Adds
Beyond expanded frequency access, the MARS mod enhances the versatility of your radio setup. For example, it allows seamless integration with transceivers that already support wideband operation. Moreover, with more frequencies at your disposal, you gain the flexibility to participate in a wider variety of communication nets, emergency exercises, and inter-agency communications.
Disclaimer: Modifying your AL-811 amplifier may void the warranty and could potentially violate regulations if not performed properly. Always ensure you have the appropriate authorization before proceeding. This mod does not open 11 meters!
How to Perform the MARS Mod
Tools Needed:
- Screwdriver set
- Wire cutters
- Anti-static wrist strap (recommended)
Step-by-Step Instructions:
- Power Down and Unplug: Before opening the amplifier, turn it off and disconnect it from all power sources. This step is critical for safety.
2. Remove the Cover: Using a screwdriver, carefully remove the screws securing the amplifier’s cover. Then remove to small access panel on the rear of the amplifier.
3. Locate the Jumper: Inside the amplifier, find the frequency-limiting Green jumper cable. This jumper grounds the tuning pot making it inactive.
4. Modify the Circuit: Depending on the amplifier version, cut the specific green wire.. Some versions require soldering, so proceed carefully.
Reassemble and Test: Once the modification is complete, reattach the covers and securely fasten all screws. Then, reconnect the amplifier and test it with a transceiver to ensure the expanded frequency range is accessible.
Conclusion
The Ameritron AL-811 MARS Mod is a valuable upgrade for radio operators needing more frequency flexibility. By expanding your amplifier’s range, you can operate 10 & 12 meters, as well as support critical communications during emergencies and broaden your participation in various radio activities.
As long as you follow legal guidelines and perform the mod correctly, this enhancement can significantly boost the versatility of your amateur radio setup.