Satellite Metrics

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fmrfman
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Satellite Metrics

Post by fmrfman » Tue May 23, 2017 2:41 pm

Gents:

We have a pair of satellite receivers that read rock steady at 50% signal level but Eb/No & C/N readings wander around (front panel LCD). Some days the Eb/No wanders up and down by a whole db. I have not observed this behavior before in my experience of working with Wegener/IDC or any satellite receivers.

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Shane
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Re: Satellite Metrics

Post by Shane » Tue May 23, 2017 9:53 pm

I have.
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grich
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Re: Satellite Metrics

Post by grich » Wed May 24, 2017 9:29 am

If you are moved to AMC18, that's something you'll expect to see, due to all the additional traffic on AMC18 and the adjacent birds compared to the nearly dead environment around AMC8.

fmrfman
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Re: Satellite Metrics

Post by fmrfman » Wed May 24, 2017 12:23 pm

We are pulling from Galaxy 4. NPR...

grich
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Re: Satellite Metrics

Post by grich » Wed May 24, 2017 4:28 pm

fmrfman wrote:
Wed May 24, 2017 12:23 pm
We are pulling from Galaxy 4. NPR...
You mean what's now G16 at 99 west? It's busy too, and you have busy C-band satellites on either side of you. Could be some intermittent splatter. Anyway, if EbNo is staying above 10, I wouldn't be too concerned, assuming you've checked your feedhorn for any developing critter issues.

Haven't had any NPR satellite experience since college, and that was in the Coastcom SCPC demod days. I noticed the giant "earth station" had been demoed the last time I was on campus.

fmrfman
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Re: Satellite Metrics

Post by fmrfman » Sun Dec 10, 2017 1:37 am

This started happening after a replacement of the coax from the roof junction box to the LNB. As part of the process we also replaced the LNB. Would mounting the LNB slightly off square have anything to do with this?

Mark

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NECRAT
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Re: Satellite Metrics

Post by NECRAT » Sun Dec 10, 2017 8:42 am

fmrfman wrote:
Sun Dec 10, 2017 1:37 am
This started happening after a replacement of the coax from the roof junction box to the LNB. As part of the process we also replaced the LNB. Would mounting the LNB slightly off square have anything to do with this?

Mark
Did that coax replacement involve you shutting down the LNB power supply? You could have electrical issues (such as a bad LNB supply).
Also you could have a flaky connection in the coax connection, causing a noisy electrical connection at the LNB as well.

However I agree with the folks above, I think you are seeing the results of a busy satellite.
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TvRadioGuy
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Re: Satellite Metrics

Post by TvRadioGuy » Mon Jan 08, 2018 9:59 pm

There's couple things you want to check Check your polarization You can be off your Pol. If you can Re-peak and pol your Antenna. If you can.If you don't have a SAT Signal Meter Or Spectrum Analyzer use your Receiver check the peak and pol of your signal. It will take a little time to get it. Make marks for your antenna position.Both Horizontal and vertical Settings. and your Base to The pole. So if you go too far you can set it back where it was. Most Satellites are 3 degrees apart and stacked up down and behind each other. It can be a nightmare if you make a mistake and if you have never align antennas. Make sure your are siting exactly on your proper polarity you can loose as much a 40 percent of your signal if you are off pol. Next thing are you down linking a Digital or analog Signal. Your LNB should be less than 0.5 Db most HD signals are weaker with older LNBs. Unlike the analog days you need 200w to saturate the Satellite Today you are going up with 50-100w.

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