TopBand: Noise

[Bob G3REP]

Some reflectees are commenting on the directivity of noise on the band.

This may be due to skywave propagation and could be an indicator of
directivity of propagtion to an area generating noise particularly near
sunrise.

While in 4S7 I used to notice the band noise first rise and fall again on
or near sunrise.  The quietest time for the band was always 1-3 hours
before sunrise.  I always put this down (rightly or wrongly) that nearer
sunrise the propagation was of a higher angle of incidence and shorter skip
to somewhere nearer the QTH.  ie 500-1500km rather than the real DX .

When one considers the state of the overhead power distribution, electrical
standards,etc both in 4S7 and S2 (and Asia in general) then you can
guarantee that there will be noise radiated in all directions from these
overhead lines and power pirates on almost any frequency!!.  It gets worse
as the dust level increases and almost dies away come the rainy season.
But of course with the rainy season comes the lightning which is another
source of wideband noise which again will carry its own directivty!!

The only real thing for sure is that one must be a masocist to try 160
metres from the tropics!!  My QRN level in Dhaka suburbs is S9 on 160, 80
and 40.

One of those noise phasing devices is on my shopping list for sure (when I
get home)!!
Are there any other suppliers apart from MFJ and has anyone any preferences??

73s & HNY

Bob Parkes
S21YP/G3REP

end




R E Parkes,  Project Manager
Granger Systems, G.I.D.P Project Office,
House No. 8, Road 19, Sector 7, 
P O Box 11061, Uttara Model Town, 
Dhaka 1230,  Bangladesh

Email: granger@bdonline.com  

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