CABL Forum - Re: C-Band Satellite interferrence

That's it .. We first noticed the pulses at about .8 Ghz, 1.1 GHz, and 1.4 Ghz. Then we happened to expand the H.P. and found the highest amplitute pulse at about 1.7 or 1.8 GHz..
We thought harmonics, but without the proper test equipment we were couldn't pursue it..Suprised the filter hasn't worked better for you.. Maybe you are closer to source...
Let me know what you find and if I can help further...

> I'm sure it is the same. I saw it on a analizer thursday looking off my G-1 odd splitter and picked it up at 1740 mhz looking through a 950-1450 lnb. the amplitude of this thing was 3 times the strength of our sat signals. I think what we are seeing is the harmonics or splatter from the main carrier. Nevertheless, if it is splattering accross the c-band, It's not operating within it's limits, or it's too high in amplitude. The more complaints i can gather up, the better chance we have of getting this cleaned up.
>
> do a search on this site for "simulsat", and read the postings. you might find it interesting. about how the radar signal travels etc. Thanks for the info, mike
> > That sounds like the same interference we were seeing.. We used a portable LNB mounted on a tripod with an H.P. in two of the systems to try and triangulate where the strongest interference was coming from.. Seemed to be N.N.W., but it varied somewhat and it wasn't conclusive.. Leading us to something airborn..The latest I have seen it is about 10:00 PM.
> > Like you said, it will happen for a while and not return for a couple weeks.. We still have a few dishes that are not filtered and it has been happening this week here as well..
> > Our H.P. only goes up to 1.8GHz, so we can't get an exact signiture and freq. of what is causing the problem..
> >
> > Some of the H.E. sites that have had the problem are:
> > Hoopeston,Il.
> > Westville,Il.
> > Paris,Il.
> > VinCinnes,In.
> >
> > I know there are more and will try and get them for you..
> > I also heard this is not just a Mid-West problem..
> >
> > > I guess what i was looking for is locations of systems having this problem. I have been seeing this blip in c-band satellite pictures since the fall of 98. It doesn't do it everyday. It may not happen for a week or 2 at a time, and then all of the sudden it's here everyday for a week, or 2.
> > >
> > > What i have noticed, is the times of the day when it happens. It will start around 7:30-8:00 am cst and continue until 11:00-12:00 and it will stop for an hour and start back up and go until 3:30-4:30 pm. Just like 8-5 work hours. And since sept 11th, i have started to notice it in the evening as well as the daytime. I never saw it happen past 6:00 pm before sept 11th. So maybe it is a government radar of some type. That's what i've always suspected. I have 1 filter in place on one of my GE-1 dishes. It took care of most of it on fox sports chicago, but it's only a 80-90% fix. And it was a 550.00 filter.
> > >
> > > I have 10 headends with a total of 78 dishes. That's 156 filters at 400.00 each. That comes to 62,400.00 for a 80-90% fix. I don't think it's right that we as a company should have to spend that kind of money just to continue to carry the same channels that we have always carried.
> > >
> > > We had contacted the FCC and they were in 1 of our systems on thursday 2-28, and it was happening at the time he was here. He asked me to see if i could find out of any other locations where it was happening, other than our systems. So they might be able to pin point it. If you know of a location where this is happening, please list it on this site. here are a few places i know of it in IL and MO. These are all individual headends. Thanks, Mike
> > >
> > > Palmyra, MO
> > > Hannibal, MO
> > > Pittsfield, IL
> > > Baylis, IL
> > > Milton, IL
> > > Kampsville, IL
> > > Springfield, IL
> > > Chatham, IL
> > > Taylorville, IL and surrounding area
> > > Versailles, IL
> > > Mt.Sterling, IL
> > > Rushville, IL
> > > Virginia, IL
> > > Manito, IL It's weak here
> > > Beardstown, IL
> > >
> > >
> > > > Many of our systems in the Mid-West had this problem..We noticed it before 9-11-01.. Tried many different thing to find it.. To make a long story short after many hours of T/S and many phone calls it appears to be RADAR..Rumor has is AWACS..We even contacted F.C.C. and they basically said it was something we need not be concerned with...Go figure...
> > > > There is a band pass filter you can install in between the LNB and the feedhorn that passes 850MHz to 1.6 GHz..The LNB receives at 3.4 GHz to 4.2 GHz and converts to 850 to 1.6 or so.. Some military RADAR is in the 3.4 to 4.2 range and the high power RADAR overdrives or clips the LNB causing the flash in analog or tiling in digital channels..The filters I mentioned cured 98% of our problem, however it will not stop any interference in the pass band(850 to 1.6).Which could be microwave, cell sites etc..This is a quick summary and I hope it is helpfull..
> > > > If needed I can get the part numbers and any info needed..
> > > > > has anyone been having problems with C-Band satellite reception? A blip that occurs every 10 seconds on certain transponders. Or, a digital channel that tiles every 10 seconds or so. If you have seen this problem on your system, please respond with the system location and which satellite channels have been affected. Thanks, Mike

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Re: C-Band Satellite interferrence