On Mon, 2007-12-10 at 17:53 -0600, Stuart Rohre wrote:
> Thanks Kevin for clarifying the actual transmission of ALE equipment during
> acquisition of a frequency.
> Another thought crossed my mind, what about the RF emanations of Plasma
> TV's? Is that in the form of a frequency sweep? Plasma TV's that hams I
> know, bought, were returned forthwith to the stores once the ham tried to
> listen to his receiver with the TV on.
> There was a general blanking of all bands in the same house. But, maybe at
> a distance, the Plasma device sounds like a sweep?
> Has anyone with this problem sent recordings to the ARRL? I would suggest
> contacting Ed Hare there, who is their BPL point man, and expert on many RFI
Some years ago I acquired an ultrasonic pest chaser. It used a couple
555 oscillators to sweep and to drive a tweeter. Supposed to chase mice
and spiders. It also clobbered ham bands and TV with harmonics. When I
found a spider's web over the tweeter opening, I moved it to the scrap
bin. I don't think it would cover a significant part of the country
without a good antenna attached.
Touch sensitive lamps used to have harmonics that swept slowly across
ham bands and I had an inverter operated fluorescent lamp with that
It would be appropriate to compare start and stop times and frequencies
heard around the country checking closely with WWV to see if all are
hearing the same signal.
73, Jerry, K0CQ
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