On 7/25/2010 9:42 AM, Mike Hyder -N4NT- wrote:
The noise blanker in my 544 is extremely effective against line noise. I'm
told it would work well with ignition noise, too. But I believe it is not
much punkin' on atmospheric noise. (I have been wrong before).
NO ANALOG NOISE BLANKER HAS EVER WORKED ON ATMOSPHERIC NOISE. The noise
characteristics its made for are ignition noise and line noise that have
a regular repetition rate but are made of isolated narrow but VERY
STRONG pulses. Unless you have a thunderstorm close by, you don't get
similar pulses from the static crashes and the noise blanker doesn't see
big enough or narrow enough pulses to work to cut them out.
73, Jerry, K0CQ
My Omni-C noise blanker was a poor imitation of the 544 blanker UNTIL I made
its circuitry identical to the latter -- then it worked very well, indeed.
It was an easy, reversible modification to the Omni-C blanker.
I wrote an extremely brilliant analysis of locating sources of line noise.
It used to be online but is no more. I can email it to anybody who is
interested. If anyone can post it and deems it worthy, I'll send it to just
one person. It is a very small file.
Mike N4NT
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