Home phone:   (408) 749-8522
e-mail: doug@dougronald.com

Bringing LPDA Back

After the enormous effort I put into this antenna, not to mention copius coin spent, I virtually had to repair it. A call to USAP to inquire about ordering parts, got me to a really nice person in sales who agreed to help. I gave him a list of first, the aluminum angle, and cross braces, and got back a very reasonable quote for fabbing those. I ordered, and USAP delivered all the boom parts I had destroyed.

So here I am, about August 2020, ready to begin on LPDA number two.

Reconstructed Boom

Reconstructed Boom

The image is of the reconstructed boom with the original undamaged front sections, to the reconstructed middle and rear sections.

KLM's LP1005

KLM Airlines LP1005A

After receiving the new aluminum from USAP, I received a call from a ham in Southern Califirnia who said he just heard of my misfortune, and had an LP1005, identical to mine, in storage! I mean, what are the chances? Further, he said he would not be able to use it, and he could sell it to me for replacement parts. We agreed on a price, with his agreeing to deliver it to my ranch, and off I go. I only wish he had found out about the accident sooner.

His son delivered the most important parts, the boom (in sections), and the elements. Here it is layed out as it was delivered, ready for me to take the needed parts, and apply them to my boom.

The antenna itself was originally owned by KLM Airlines in the Netherlands, surplused by them, then purchased by the ham in So. Cal. where he shipped it from Europe to the US.

Hydraulic Winch

Backhoe Hydraulics to Winch

The 410G has an auxillary hydraulic on the boom which I have connected to the 48,000 pound pull winch. The new wire rope pull cable is now 5/8 inch, up from 1/2, just to improve my safety margin. This is the largest wire rope allowed by the antenna hardware.

Wire Rope Interface

Winch to Pull Cable Interface

My "accident" on the first antenna disaster was caused by this interface where I had not torqued the wire rope clips to specification, and the wire rope slipped out. That is not going to happen twice. Now I have Crosley clamps on 5/8" rope, and have torqued each of these to the 130 foot pounds required. The larger cable comes up from the winch and is 7/8" in diameter, meeting my hoist cable at 5/8" diameter.

Boom Mated to Mast

Boom and Mast Truss Joined

Here is the completed repaired boom truss, now bolted to the mast plate. I have completed two weeks work thanks to some teriffic weather. Some days, thanks to California wildfires, I had to work in dense smoke, with an N95 mask for protection.

Boom Mated to Mast

Left Side of Antenna and Mast

Another view of the mated boom and mast. Getting those two mast plate bolts in was a real bear. With two people, it would have been much easier!!

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