NBC Mux On 105W

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Flux like that is typically terrestrial born interference in my experience.

WVMAN, the ABC issue could be that air conditioning around you is cycling on and off in prime time, vs during midday it's just on. Arc in those contactors, or from dirty brushes in the condenser fans can make broad-band racket clear up into C-Band.

Filters on the waveguide can sometimes help -- prevents AGC pumping / compression point IMD. I had a case two or three years back on an antenna near a furniture factory where an evanescent mode waveguide filter between the feed and the LNB turned out to be the magic bullet cure for intermittent signal q drops.

But if that interference is "in band", you have to hunt it down and fix it.

One instrument to hunt interference down with is just simple open wg on an old LNB, connected to a signal strength meter or some sort (analogs are quicker than digital ones, easier to find intermittent trash) and power. Aim it at things that might be generating arcs (motors, contactors, power poles, small engines, the like). Arcs are usually very broadband noise sources.

Good hunting!
 
Hi,

I wonder if there is some kind of electrical interference causing my issue with the NBC mux on 105.
Without touching the dish, I'm back up, today to a signal strength of 51-67%. Yesterday it was 32-48%.

John
 
Hi All,

This will be my last post on this thread.
Yesterday afternoon I got my highest signal reading on the NBC mux, it was varying between 63-72%.
Later in the evening it dropped back down to 32-51%. The were no weather issues and I hadn't touched the dish.
Guess I'll just have to live with this issue as picture quality remains good with the low numbers.
Thanks to all for their input.

John
 
Hi All,

This will be my last post on this thread.
Yesterday afternoon I got my highest signal reading on the NBC mux, it was varying between 63-72%.
Later in the evening it dropped back down to 32-51%. The were no weather issues and I hadn't touched the dish.
Guess I'll just have to live with this issue as picture quality remains good with the low numbers.
Thanks to all for their input.

John
It's still a steady 75Q here in Central PA. Hoping you can figure it out but at least the quality is strong enough to keep the picture/audio locked. :)
 
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Flux like that is typically terrestrial born interference in my experience.

WVMAN, the ABC issue could be that air conditioning around you is cycling on and off in prime time, vs during midday it's just on. Arc in those contactors, or from dirty brushes in the condenser fans can make broad-band racket clear up into C-Band.

Filters on the waveguide can sometimes help -- prevents AGC pumping / compression point IMD. I had a case two or three years back on an antenna near a furniture factory where an evanescent mode waveguide filter between the feed and the LNB turned out to be the magic bullet cure for intermittent signal q drops.

But if that interference is "in band", you have to hunt it down and fix it.

One instrument to hunt interference down with is just simple open wg on an old LNB, connected to a signal strength meter or some sort (analogs are quicker than digital ones, easier to find intermittent trash) and power. Aim it at things that might be generating arcs (motors, contactors, power poles, small engines, the like). Arcs are usually very broadband noise sources.

Good hunting!

All of my electronic gear has a Line Conditioner and surge protectors on it. The conditioner filters out all the trash that comes in on the power line, and keeps the voltage constant. If the voltage goes high or low, it compensates for it. It's as clean as home power can be. In conjunction with these devices, I have a huge commercial back up that keeps everything running when the power goes out or flashes off and on.

I'd be surprised if my air was causing the problem. I've actually pulled the plug running everything and let it run off the UP's unit and still had the fluctuation in signal levels. My wife gives me the evil eye when I do stuff like that because she's usually watching something when I do it. :)
 
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Are you over-illuminating the dish? The more the feedhorn protrudes from the scalar, the more of the dish it sees. Go too far and it sees beyond the edge of the dish and picks up ground noise. Ground noise looks great on the signal strength meter. ;) But makes the quality drop like crazy. For an experiment try pulling back the feed about a 1/4 inch and see what that does during the day.
 
Are you over-illuminating the dish? The more the feedhorn protrudes from the scalar, the more of the dish it sees. Go too far and it sees beyond the edge of the dish and picks up ground noise. Ground noise looks great on the signal strength meter. ;) But makes the quality drop like crazy. For an experiment try pulling back the feed about a 1/4 inch and see what that does during the day.

I moved mine in and out a couple times to see what it did. I have the best results setting it according to the dish specs. When I found Start TV, I was getting an 87/47 signal level, but it doesn't break up at all. Never saw a signal like that before. Usually more even. Everything else on that satellite is fine.

The channels that gave me trouble for a while was the Grit MUX on Galaxy 19, but I have that ironed out now and those channels are working fine now. That problem was an "assumption" that the person who originally installed the dish got it right. Well, you know what assuming does for you. :D
 
Isn't it that time of year when the sun passes directly behind the satellites, usually in the afternoon? It usually causes signal lost for a few minutes until it moves behind the next satellite to the west.
 
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