[Elecraft] Noise in the Mideast

Merv Schweigert k9fd at flex.com
Sun Oct 12 14:23:55 EDT 2014


There is Chinese Hainan Island radar that is very active, and usually on 
7MHZ.
it covers 100KHZ at least,   the "smaller" 10khz wide signals are also 
radar,  over the
horizon,  the smaller ones usually are several seconds of signal then 
space and
repeat..    the Hainan dragon is constant on all the time when operating.
it is over S9 here on 40 when its on...
Not sure if thats what your hearing or not,  K3 blanker will not handle 
it,  helps a
little but not much,   I asked Elecraft about it and they mentioned an 
experimental
change of some components that may help,  but I do not have the info and 
have
not tried it.
73 Merv K9FD/KH6

> Since getting on the air from Israel I notice an interesting noise on 
> the bands 7 and 10 mHz and to a lesser extent on 14 mHz. It is a 
> wideband 'schmutz' (technical term) which can take from 10 to 50 or 
> 100 kHz. Its amplitude drops of gradually as you move away from the 
> center. It reaches S9 levels sometimes on 7 mHz.
>
> It does not look like the typical switching supply noise. I do not 
> hear it on 3.5 or 1.8 mHz.
>
> The K3's DSP noise blanker seems to help a little, but not much.
> Does anyone know what it is? Could it be some kind of spread spectrum 
> transmission? It could be coming from anywhere in Europe or the Mideast.



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