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GAM Backstay Antenna System

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Original price $3,605.53
Original price $3,605.53 - Original price $3,605.53
Original price $3,605.53
Current price $2,704.15
$2,704.15 - $2,704.15
Current price $2,704.15

GAM Backstay Antenna System

The GAM/McKim split lead single side band antenna is a favorite amongst sail boaters because it eliminates the need for backstay insulators forever. The split lead antenna simply press fits onto your existing backstay wire with no special tools or equipment required. The GAM/McKim is secured at the base by a hard grade plastic T clamp and requires a back stay length of at least 34 feet.

Communications Expert Gordon West Reports, “I have done numerous SSB ham and marine radio checks with this system and have found no discernible signal losses, even when used with a well-grounded backstay aboard a steel-hulled vessel.” The Split Lead antenna’s. . .”twin radiating elements. . .bang out a signal as if they were suspended in mid-air.” – from Sail Magazine’s “Ask Sail” column, October 2005.

Click here to download a PDF of product features.


The split lead antenna installation requires no alteration of the backstay thus preserving full mechanical integrity of the backstay wire. All RF elements of the antenna are fully insulated eliminating the possibility of the shock hazard posed by the bare wire connection in conventional backstay antennas.

Ease of Installation

No cutting, no swaging, no measuring, no special tools, no special skills required. Simply press fit the GAM/McKim over the existing backstay wire, clamp at bottom and secure in place with included Zip-Ties.  Click here for installation instructions.


Active elements are designed for RF, meaning they are more conductive than the stainless steel backstay wire. Lead wire connections are waterproof and electrically sound. The antenna’s insulated housing reduces precipitation static, often associated with heavy squalls and thunderstorms.

Stowage and Portability

The Split Lead antenna can be coiled up to a diameter of approximately 26” for ease of storage. It can be easily removed when the mast or backstay require work and can readily be transferred from one vessel to another.


The outer housing is very durable, resistant to weathering and, since it is under no mechanical stress, should last for many years in the marine environment.

    Model:  GAM-BACK

      Techical Details


      • Dimensions: 25" x 25" x 3" (Stored)
      • Frequency: 4 MHz
      • Feedline: 15' (GTO 15)
        • Actual antenna is 34' long
      • Power Rating: 150 Watts


      The GAM/McKim Split Lead Antenna is designed for Single Side Band Marine Radios with Tuners. You will need 34 feet of space on your backstay. The backstay diameter should be between 1/4" and 7/16". As the name implies, the center tube of the antenna housing is split which allows it to be put onto the backstay slid up the stay until you have reached the height that you desire for the bottom of the antenna housing. The antenna is supplied with 15 feet of GTO-15 for connection to the tuner.