UPDATE – Just to set the record straight, I no longer believe that RF was what caused my F-150 to lose its mind. I had a similar problem not too long again, and there was no Contest. Ford had to replace some wiring harness inside the transmission ($$$$$$ for them). That seems to have fixed the problem.

 

After a weekend-long CW contest at my Home, I jumped into my Ford F-150 to head out, and it was acting very strange. It seemed like the automatic transmission was dead or dying. I knew it was a little touchy going into 2nd gear at times, but it had been working just fine when I parked it for the weekend. I thought my week was ruined and I would have to call for a tow of my truck for an expensive transmission repair.

As I headed out of the driveway, shifting was still awkward. Then I noticed that as it changed gears, the dash display still said I was in 3rd gear. Once I saw that I knew something was fishy. So I went back to the house. I went through a couple power on-off cycles and things started to change. The dash display went nuts briefly, but then it started to come back to normal.

Seeing this change in behavior made me finally realize what had happened. I had parked the truck with its HF rig and screwdriver antenna right under one of my wire antennas, a ZS6BKW. The tip of the truck’s HF whip was directly under the antenna and only about 20 feet away. My guess is that there was RF coupling between the Home antenna and the wiring in the truck. As a result of the RF, some computer memory in the truck got corrupted. Eventually the vehicle must have loaded some historical or factory settings. After that, all was well again.

So now, when I park near the Home HF antennas, I remove the whip from the truck. I plan to do some more RFI mitigation soon, but for now this seems to have solved the problem.

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