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Hall of Flame!

– Posted in: Hall of Flame

At one time or another most of us have had an accident with our antenna systems where fire was involved.  As a member of this club, I can say that its never fun when something burns up as it usually happens in a difficult to reach and repair location.  Below are images from a few members of this hallowed club.  Check back regularly as I expect the offerings to grow over time.


Roger, VK4YB, recently submitted this offering which shows the awesome energy associated with 450-watts of RF power at a high voltage point on one of his end-fed antennas.  Note that these antennas are supported at something like 100-foot above the ground so the branch that this wire was adjacent to  must have burned up before the wire fell and did this damage.


Laurence, KL7L / WE2XPQ, provided this iconic picture a couple of years ago after a bolt (the one pictured), got too hot after being subjected to 55-amps of RF current at 137 kHz.  Laurence repaired the ATU, which has traveled all over the world with him but the bolt had to be replaced.


Larry, W7IUV / WH2XGP, reports that this is what happens when “dirty ice” builds up inside the coil form.  He indicates that the first picture is the covered coil while the second image shows the cover removed and the full extent of the damage.


This next offering is mine.  It occurred on a very cold January night in 2014.  I can only imagine that the cold temperatures  stiffened the plastic tubing I was using as an additional layer of protection with my PTFE-insulated high voltage leads off of the coil.  The stiff tubing  probably was stressed when I moved the variometer after a CW session back to WSPR.  So much for extra protection!  Fortunately the power supplies for the amplifiers responded to the over-current conditions and stopped the otherwise runaway event.


Neil, W0YSE/7 / WG2XSV, now located in Washington state, reports that “When in Utah, I had an incident happen at the base of my vertical antenna. I was “hot switching” the coax taps at the base of the loading coil and things went sour. I discovered this arc-over on the back side of my PVC “insulation”.   I had to re-mount the base on a new PVC pipe to be able to transmit again on 630 meters.”


John, WA3ETD / WG2XKA, submitted this offering of one of his original 630-meter verticals:

“At one point the TX vertical consisted of 35′ telescoping aluminum tubing, coupled to 2x, 100′ top wires on 4′ spreaders.  The 2″ bottom section was insulated with a 1/8″ thick black PVC tube, clamped to a piece of 3/4″ pressure treated plywood, which in turn was clamped to an iron steam pipe.  The PVC broke down and burned thru to the conductive copper sulphate plywood, as seen.  The vertical now serves as my RX only vertical, no HV!”


I know there are a lot more stories and images!  Send them to me for inclusion with your story!  MF, LF, VLF – it doesnt matter!  Let’s be careful out there!