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Mystery Transmission

06/19/2009

When I tell this story to friends who are not hams all I get is a blank look, but I know you will understand why the event left me feeling amazed and disoriented. It started out mundanely enough. I was cruising the neighborhood of Oakland, California’s Rockridge Café, a favorite grill of mine in which to have a burger or some soup at lunchtime.

As I motored slowly along Forest Street, a block or two before College Avenue I began to hear Morse code, just slightly faster than I can copy in my head, but definitely Morse. Rolling down my window to hear a little better I realized it was a car horn, sending at 20-some words a minute. When I drew abreast of the car sending the code it was completely empty. I could clearly discern that each and every group of dits and dahs was a letter and not just some random making and breaking of a short in the horn circuit.

Shaking my head in puzzlement I continued looking for a parking space and, finding none, I turned right on Lawton and went around the block. Arriving back on Forest I discovered that the car was still sending what sounded like the middle of a long ragchew. Pulling up next to the car I stopped, looking all around to see if someone was playing a trick on passersby, but there was no one in sight.

Now here’s the bizarre part, and at the same time the thing that gave me a clue as to the explanation of the mystery. Going along with what I assumed was a joke, I expressed my appreciation by sounding out HI HI HI on my own car horn. Instantly the sending stopped, then, after a long pause, resumed.

Aha. Suddenly I realized what must be going on. Somewhere within earshot of my horn was a ham with an indoor antenna (I had already looked around for exterior ones). And, in a one-in-a-million chance, there happened to be a car parked near his house with a defect in the horn circuit, perhaps some corrosion, that was rectifying the RF and somehow shorting the horn. Or perhaps the rectification was occurring in some solid-state component of the horn circuit. This notion was corroborated by the fact that the CW was sounding at a much faster rate than one can send Morse using the horn button itself.

I had a good laugh envisioning the operator, startled in the middle of his ragchew, who suddenly hears someone outside his house sending HI HI HI on his car horn. If he heard my car horn why didn’t he hear the original car horn? Well for two reasons I can think of: Going at such high speed the tone was pretty light and tentative — not very loud. And it would have coincided with and may have been masked by his CW sidetone.

Finally finding a parking space, I went on to have a good lunch at the Rockridge. Later my only regret was that I didn’t think to send a QRZ (Who is calling me?) with my own car horn and sign “de W6EW.” If I’d had time to dig out a pencil I might even have been able to read the mail (listen in.) and copy his call when he signed during his exchanges. Perhaps I could have enticed the operator to come out to the street so I could meet him or her.

If anyone knows the ham living near the corner of Boyd and Forest in Oakland, he or she might find this story amusing if you will be kind enough to pass it along.

Denis "Doc" Franklin, W6EW, has been a ham for 42 years who, since his retirement from medical practice in 2000, has written several previous QST articles on the use of HF Winlink2000 on oceanographic research ships and Winlink HF/VHF/UHF in emergency and disaster communications applications.

Though proud of his non-ham children, a college professor, a helo pilot, a trial lawyer and a digital production manager for Hollywood films, Doc is especially hopeful that the two grandchildren who have expressed an interest in ham radio will develop an early proficiency in and enjoyment of CW, a skill at which he feels he missed out by skipping over the Novice step when first licensed. He now struggles daily to "get over the hump" and copy high speed Morse by the word instead of by the letter.

Denis "Doc" Franklin, W6EW



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