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Re: US Warships jamming Lebanon Internet


From: Denys Fedoryshchenko <denys () visp net lb>
Date: Tue, 8 Feb 2011 14:34:38 +0200

On Tuesday 08 February 2011 14:41:29 Adrian Chadd wrote:
On Tue, Feb 08, 2011, Denys Fedoryshchenko wrote:
On Tuesday 08 February 2011 14:18:59 Adrian Chadd wrote:
On Tue, Feb 08, 2011, Denys Fedoryshchenko wrote:
 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.

Can you get access to some kind of spectrum analyser kit to see what
the kind of interference is?



Adrian

Yes, on short (few minutes) sweeps it is clean. During long time run,
with 100 Khz resolution, if we run few hours we can catch anomalies on
the carrier. Important note: this snapshot done on spectrum analyser in
Europe, same transponder, and results similar, so it looks like
interference is on transponder. Issue start to affect us at same time
when people in Lebanon got local interference issues.

Here is snapshot of carrier spectrum with anomaly:
http//www.nuclearcat.com/PICTURES/interference.jpg

And does this interference similarly screw up being able to RX data from
the transponder whilst in Europe?

(eg, if you stick a modem on RX-only in Europe (ie, no uplink) and then
just lock onto the signal and decode whatever happens, do you suffer
the same problem?)
Difficult, in Europe EIRP of transponder is too low, to try.
By the way interference almost disappeared yesterday, and it's much better 
today.


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