Beam Truss Components Built at W0CG

The trade winds in Curacao blow strongly all year around. In the summer months, they are particularly fierce, averaging 20 knots and frequently gusting to 35 knots, day and night. This places extreme loads on the yagis. In order to discourage the yagis from twisting the towers, and to stabilize the booms of the large 20 and 15 monobanders, we added considerable extra mechanical strengthening. Following the design example of K3LR, the three largest beams received triple trusses, one overhead and two laterals. The laterals were trussed with Phillystran and the overheads with 1/4 inch EHS steel guy cable. In addition, 0.19 inch Phillystran lines were run from the three largest booms to guy points on the ground and brought taught with turnbuckles. This greatly reduced torsional loads on the towers during peak wind times.

The highly corrosive seaside environment is another challenge, thus all components were made from galvanized, aluminum, or stainless parts, or were aggressively painted before installation. In addition, all eyes are of FORGED construction.

W0CG built all of the components and then transported them to CUR in VERY heavy checked bags on the airlines on 23 September 2001. What you see below is in his driveway prior to packing for the trip south.


Most of the parts for the boom wind trusses, minus the 400 feet of Phillystran.	Representative bracket for attaching a Phillystran boom truss to a boom, this for the US/JA 20 meter yagi.

Shackle for ground attachment of the boom trusses. W0CG picked this (and other parts) up in a field where a tower had been cut down and abandoned in Iraklion, Crete, Greece, in 1992. That's recycling!!	More of the boom truss assemblies.

A bracket for the 15 monobander laterals to attach to the 3 inch boom.	An aluminum lateral boom standoff.

The boom standoff for the overhead truss for the US/JA 20 monobander.	More brackets for boom laterals.

Boom overhead attachment point.	Aluminum lateral standoff bracket.

Most of the components for the US/JA boom truss system.	More wind truss parts.

There were over 300 individual parts involved.	The guy attachment point for the Europe 20 and 15 yagi booms.