HFU HF Underground
General Category => General Radio Discussion => Topic started by: mapleleaf on March 22, 2008, 1739 UTC
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For the past week or so, I've been hearing a really annoying noise, often on or near 6925 as well as many other places accross the shortwave bands. It sounds like a distorted wefax or sstv. I first thought it was a spur or harmonic from the local Coast Guard transmitter site which does broadcast weather charts. Problem with that theory is that the noise never seemed to stop and tended to move around in frequency.
Today I decided to consider the possibility that it was coming from something in the house. My first target was a dbs satellite receiver and lcd tv in the same room as my R75. I pulled the ac plug for the sat. rec. and voila! the noise is gone! Very pleased with myself, I sat down at the R75 and spun the dial only to find that the noise was stiil there but had changed freq. when I pulled the plug ??? I repeated the process and the same thing happens!
The hunt continues....
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I've used to techniques to find QRM sources:
1. Use a portable radio, and go around the house to locate the source.
2. Flip breakers off until the QRM goes away, to identify which circuit the offending device is on. Then you can unplug individual devices.
Note that the latter is best done when the XYL is not at home ;-)