OT - 30.53 KHz carrier pulses on 40 meters

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OT - 30.53 KHz carrier pulses on 40 meters

mike
I have been noticing a 1 second on / 1 second off carrier at 30.53 KHz intervals on 40 meters. For instance I just captured a P3 screen showing the pulse at 6.97681, 7.03788, 7.06841 and 7.09894 MHz. At first I suspect a new switching power supply, but the signals are still there when running off a battery. Anyone know what this might be? I am puzzled.  73  ..mike  AI6II
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Re: OT - 30.53 KHz carrier pulses on 40 meters

Elecraft mailing list
Re:  I have been noticing a 1 second on / 1 second off carrier at 30.53 KHz
intervals on 40 meters.


My washing machine does something very similar to this.  The source is very obvious since the carriers rise up and down in time with the washing machine agitator motion.  I’m not saying that is what you are hearing, but it just shows that EMI is not a priority for modern appliance designers.  It is the first time that I have had a washing machine that has been the source of an EMI problem.  I haven’t spent much time trying to figure out how to eliminate it since hitting the washing machine OFF button makes it go away.  It was nice of the manufacturer to add that feature  ;-)


Mark,

KE6BB
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Re: OT - 30.53 KHz carrier pulses on 40 meters

mike
I have eliminated all sources from inside the house/shack. I turned off the AC mains and ran the K3/P3 on battery. The signals were still there, a strong S6. I will have to devise a way to sniff a round the neighborhood. I have only found the pulses on 40 meters, but there are nine of them within 7.0 to 7.3 MHz. Only two are in the first 48 KHz of the band. I guess I can live with losing 7.007 and 7.037 MHz, it's just a bit irritating!  ..mike  AI6II
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Re: OT - 30.53 KHz carrier pulses on 40 meters

Bill Turner-2
------------ ORIGINAL MESSAGE ------------(may be snipped)

On Tue, 9 Dec 2014 11:53:31 -0700 (MST), you wrote:

>I have eliminated all sources from inside the house/shack. I turned off the
>AC mains and ran the K3/P3 on battery. The signals were still there, a
>strong S6. I will have to devise a way to sniff a round the neighborhood. I
>have only found the pulses on 40 meters, but there are nine of them within
>7.0 to 7.3 MHz. Only two are in the first 48 KHz of the band. I guess I can
>live with losing 7.007 and 7.037 MHz, it's just a bit irritating!  ..mike
>AI6II

REPLY:

I had something very similar several years ago. Turned out to be a
battery charger for a golf cart about a hundred yards from my house.
 I found it by snooping around with a portable short wave radio. When
I contacted the maker of the charger they were very cooperative and
fixed it promptly. Fortunately the homeowner was also cooperative and
didn't mind me snooping around his house.

73, Bill W6WRT
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