US Warships jamming Lebanon Internet

Tue Feb 8 12:34:58 UTC 2011

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?

Tom