My brother, John, KB2SIL has had one of these up for the last 4 years, which considering the CNY winter WX bodes well for the survivablity. This was posted last year, so if you think you have seen it before, you probably have... =================================================================== This was originally posted on packet, and published in the BARK (Brockport Amateur Radio Klub) newsletter and the Rochester VHF Journal...Keith, WB2VUO _ PPM: A Light-Duty PVC Pipe Mast Over the 25+ years that I have been a ham. I have seen a few antenna supports, [ and have built a few, myself ]. One of my brothers, John, KB2SIL, has come up with a light-duty, inexpensive and easily built PVC Pipe Mast, PPM for short. On John's first attempt on the PPM, he acquired (3) 10-foot lengths of 1 1/2" NPS PVC pipe. The actual outside diameter of this is 1.99", with a nominal ID of 1 1/2". He put the three lengths together with straight couplings and PVC cement. However, when he tried to raise the mast into the air, the cemented joints failed catastrophically, resulting in PVC hash and scraps all over the back yard. Something else needed to be done to improve the mast mechanically. In PPM, Part II, John used a piece of the PVC for sleeves at each joint, cutting a pair of 2-foot lengths from some of the scrap, and splitting them lengthwise with a hacksaw. These split sleeves were held in place with four stainless steel hose clamps, two above, and two below the joint. This proved to be entirely adequate, and he set the mast up at the end of the house. Using a mast bracket, re-drilled for a larger U-bolt, and a set of light Nylon guys at he 20-foot level, he erected an 80 - 10 meter G5RV. This put the feedpoint up at 29-feet, just right for the 300-ohm twinlead, and the plastic mast doesn't affect the balance on the line! As a bonus, and seeing that he didn't have his ticket back then, I checked out the antler for him. It plays as expected on not only 80 - 10 Meters, but also on 6 Meters. We were able to raise a 6-Meter repeater about 40 miles south of his QTH with around 3 watts. The SWR was normal for the HF ranges, being best on the 20 meter band, and was within the ATU's adjustment range on all the other HF bands. John is in the Syracuse area, with a fairly well-sheltered back yard. Out here on the windswept flats [swamps] of Bergen, I wouldn't expect the PPM to survive, unless I guyed it 6-ways to Sunday, but I am eyeing the leeward end of my barn as a possibility. I would think that the PPM would work well in almost any urban/suburban lot, and being PVC, one wouldn't have to worry about corrosion and/or water damage. ================================================================= If you try out John's PPM, drop me a line here. 72/73, Keith, WB2VUO.
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