US Warships jamming Lebanon Internet

Denys Fedoryshchenko denys at visp.net.lb
Tue Feb 8 06:32:27 CST 2011


On Tuesday 08 February 2011 14:34:58 TR Shaw wrote:
> On Feb 8, 2011, at 6:59 AM, Denys Fedoryshchenko wrote:
> > On Tuesday 08 February 2011 01:42:42 George Herbert wrote:
> >> On Mon, Feb 7, 2011 at 2:23 PM, Ryan Wilkins <ryan at deadfrog.net> wrote:
> >>> On Feb 7, 2011, at 4:06 PM, Michael Painter wrote:
> >>>> Hi Denys
> >>>> I doubt it's intentional jamming since I've had the same problem.
> >>>> Aegis radar is very high power in full radiate mode and as such
> >>>> creates problems for Low Noise Amplifiers listening at 3.4-4.2 GHz.
> >>>> Someone needs to talk to Microwave Filter Company.
> >>>> http://www.microwavefilter.com/c-band_radar_elimination.htm
> >>>> 
> >>>> --Michael
> >>> 
> >>> +1 for Microwave Filter.  They've helped me out in a couples jams
> >>> before. They're very responsive and the products are good, too.
> >> 
> >> I think people in San Diego and near Norfolk, VA have the same problems.
> >> 
> >> The C-band frequencies are 2x those of the S-band (4-8 GHz for C, 2-4
> >> GHz for S); if the SPY-1 / SPY-1D radar is frequency hopping it may
> >> well step on someone's C-band links at twice the radar's basic
> >> frequency.  Just need a filter to remove actual S-band frequencies
> >> from C-band feeds.
> > 
> > I try to install C-Band bandpass filter, no effect at all, so it is
> > in-band interference. Putting foil (yes i try almost everything) near
> > LNB doesn't affect interference level too.
> 
> It can come in from other places as well. Inductance via
> unfiltered/poorly-filtered power, poor I/F cabling as well as via other
> sources.
> 
> Have you tried using a spectrum analyzer to characterize the signal in the
> ether and compare it to what you are seeing in your systems?
Yes, for sure i did. I am running C-Band at this location not first 		
years, and know very well how industrial sources looks on spectrum analyser, 
and it is easy to triangulate them (i can go up to 9Ghz).
Vessel radars also relatively easy to catch, especially with sound 
demodulation.

> 
> Tom




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