Topband: What is this!

[Tom Rauch]

Hi Bill,

> I do not operate AM mode but, in the AM mode on my IC-735, I have
> an "S" meter reading that is always around an "S9".  On sideband, this
> "S9" becomes an "S4-5". 

The "band noise" from the north has been very high lately. The 
noise I hear is propagated noise, because I am in a rural area and 
my antennas are a long distance from noise sources.

Sometimes the band is just "noisy" in some directions with a hiss. 
It could be an accumulation of many thousands of noise sources 
propagating in, or from some ionospheric source. I have no idea, 
except it is not coherent noise. It is white noise.

Because it is a "smooth" noise, narrow filters reduce its level 
without making it "ring out" like a raspy noise. I doubt what you 
hear is from power lines, because unless the lines are DC they are 
always modulated at 60 Hz or multiples of that. If it is a voltage 
breakdown issue on a single phase line, the noise is generally 120  
Hz (one pulse one each crest of a cycle).  

When the band was open to Asia last night and this morning, I also 
heard that "buzzing thing" that appears every few kHz. It was 
discussed here a few months ago, and the conclusion was it is 
from Asiatic Russia or something near there.

73, Tom W8JI
w8ji@contesting.com


--
FAQ on WWW:               http://www.contesting.com/FAQ/topband
Submissions:              topband@contesting.com
Administrative requests:  topband-REQUEST@contesting.com
Problems:                 owner-topband@contesting.com