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In 1962 I was hired as a transmitter engineer with radio station WAEB in Allentown, Pa. The transmitter site was in Whitehall Township, several miles north from the studios in Allentown, and the site covered a rather large, clear area to accommodate five 350 foot towers. My job was to take meter readings to satisfy FCC requirements and keep the AM and FM transmitters on the air.

One evening, during a violent thunderstorm, I heard a very loud crack outside the transmitter building.  This sound was indicative of a close lightning strike. Instantly my eyes were drawn to the glass window on the front of the AM transmitter,  which displayed the large vacuum tubes.  I was amazed because there, in the window, was a very bright, very white ball, about the size of a golf ball, lightly dancing on the high voltage buss attached to the top of one of the  tubes. The ball was round but it was not solid, rather is looked open with very tiny sparks emanating everywhere from within, like the sparks from a 4th of July Sparkler.  The floating/slightly dancing motion reminded me of a Karaoke bouncing ball. There was a distinct "hissing" sound which accompanied the ball. The ball was sitting on the horizontal high voltage buss feeding the right hand Machlett ML-357B tube.  The ball very slowly 'walked' from the top of the tube anode to the back of the tube section taking approximately 4 seconds.  It instantly dropped or got sucked, 3 feet down into the high voltage power supply compartment at the bottom of the transmitter. There was a bright flash inside the power supply compartment and the transmitter went off the air. My first impressions were: amazement and fascination with the generation of the ball itself; how slowly it walked across the high voltage buss by the tubes; how very quickly it dropped into the power supply cabinet and why it took that route to disappear. 

I didn't have much time to dwell on what I had just experienced, because my job was to put the transmitter back on the air. Since the transmitter was so very reliable, it was my first time to actually work on it and I could feel the pressure to fix an unknown problem.

To shorten the story, I removed the mercury vapor rectifier tubes and replaced them with two from a special rack that were previously pre-warmed (to get the mercury to the bottom of each tube, so the mercury wouldn't short out the tube) and fortunately the transmitter came back up.  Days later, during maintenance, the removed rectifier tubes were found to be good.  I realized that I could have merely reset the breakers and the transmitter would have come back up.

I revisited this webpage in July 2021 and I still remember the event as if it were yesterday.  It was one of the most amazing and interesting things I have ever seen in my life.  I don't know how the ball was created, I don't know if lightning stuck one of the towers or struck the many hundreds of feet of 'copper pipe coaxial transmission lines' or what, it is a complete mystery.  There is not a lot of specific information, on the internet, about the how the ball is generated, just a few observations.  I was at the transmitter site many times during strong thunderstorms and why it happened this particular night, I cannot provide an explanation.


Below is the WAEB 1000 watt Western Electric 443A-1 AM transmitter where the ball lightning took place.

click HERE to see more information on the Western Electric 443A-1 TRANSMITTER




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