white springs issues?

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avg1joe

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Oct 27, 2006
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Southern Maine
I was just out re-aiming my dish and am getting good signal across the arc except on white springs on 129w. Is this an issue on their end or mine? Anyone getting good signal? I was able to get excellent quality off a scrambled tp (data?) at the same location but not white springs' tp.
 

john green

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Dec 22, 2005
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Georgia
FWIW - I have always gotten low signals on WSTV although the picture comes in fine with no break-up or pixelation.

Same here. I can get Whitesprings perfectly with only a 60 quality on the Coolsat. I have never seen another signal come through that low.
 

Keith Brannen

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Jun 2, 2006
1,881
639
Southwestern Ontario
I was just out re-aiming my dish and am getting good signal across the arc except on white springs on 129w. Is this an issue on their end or mine? Anyone getting good signal? I was able to get excellent quality off a scrambled tp (data?) at the same location but not white springs' tp.

Signal's about where it normally is for me (60's) but with some fluctuation, but that is due to the heavy rain we received not too long ago so the LNB/dish still has some water droplets on it.

On my Pansat WSTV can drop to the low teens without pixelation.
 

avg1joe

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Oct 27, 2006
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Southern Maine
Thanks for checking. I had nearly no signal when I posted but since have strong signal and quality in the 20's without changing anything. Amazingly its watchable with the quality reading that low. Very odd. Usually if quality dips into the 40's I get pixelation or lose signal with my box.
 

Mr Tony

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Supporting Founder
Nov 17, 2003
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Mankato, MN
White Springs has a FEC of 1/2 which is as low as it can go (most FTA channels are 3/4)...so you can get by with a low signal quality..now if it was a 7/8...oof da...then you need about a 75 quality signal for stability :)

FEC's are 1/2, 3/4, 5/6, 7/8...1/2 means you have lots of leeway for signal...7/8 you need to be balls on for a stable picture....and sometimes that doesnt even help if the dish is too small
 

Greysquirrel

SatelliteGuys Family
Nov 13, 2003
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I have a similar problem with WS, here today gone tomorrow and I also get low quality, in the 30's but once it gets to around 42 I have no problem with it, in fact most of G10 in the mid 40's and I have no problem with the picture. Most other sats are in the high 50 or 60 range just the far West birds I have a low signal.
 

Mr Tony

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Supporting Founder
Nov 17, 2003
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Mankato, MN
sounds like the dish isnt aimed 100% correct...Unless you have a box that really reads low for signal, G10 should be higher than that
 

GreatFTA

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Aug 14, 2006
1,389
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Mississippi Delta
I never have any problems with WS Tv, even tho the signal strength is low on mine as well. I am glad to get those old movies that my parents and grandparents used to watch...
Iceberg, I always wonder what those FEC's are for. Can you shine some more info about them so we can understand them?
 

GreatFTA

SatelliteGuys Pro
Aug 14, 2006
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Mississippi Delta
QUOTE=Greysquirrel;1003884]I have a similar problem with WS, here today gone tomorrow and I also get low quality, in the 30's but once it gets to around 42 I have no problem with it, in fact most of G10 in the mid 40's and I have no problem with the picture. Most other sats are in the high 50 or 60 range just the far West birds I have a low signal.[/QUOTE]

Greysquirrel, go to this link:
Footprints by Dish Size - Adjusting the Polar Mount for Prime Focus Antenna - C/Ku-Band Satellite Systems - Tuning, Tracking, Azimuth, Elevation, Declination Angles, F/D Ratio, Focal Distance, Inclinometer, LNB/Feedhorn Assembly, Actuator Assembly, C
When you get there, scroll till you see a chart that shows the arc tuning troubleshooting. It will have the caption on top that reads PHILOSOPHY OF
TUNING DISH TO SATELLITE ARC.
It should give you a ideal of how to fine tune your dish so it should track the entire arc accuarely.
Good luck!
I was going to put this chart on this post as a attachment but I cannot figure out how to do this, so you wouldn't have to go to the website and find this chart. Sorry...
 

Greysquirrel

SatelliteGuys Family
Nov 13, 2003
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sounds like the dish isnt aimed 100% correct...Unless you have a box that really reads low for signal, G10 should be higher than that

I have sat outside and tweaked the dish E & W, up and down and it's getting the best signal at the setting it is at. Most other sats are in the high 50 or 60 range.
My box is a Neusat 6000 Premium and I have no way of comparing the scale of the quality reading to another box.
 

Mr Tony

SatelliteGuys Pro
Supporting Founder
Nov 17, 2003
299
48
Mankato, MN
Iceberg, I always wonder what those FEC's are for. Can you shine some more info about them so we can understand them?

North American MPEG-2 Information

What's FEC?

Satellite transponders are rather noisy communications channels are are therefore subject to a large number of errors when a signal is sent through them. Because satellite transmissions are broadcast, the receiver cannot send a message to the transmitter to say "I didn't get that last piece of information, please re-transmit it". As a result, Forward Error Correction is used, where the transmitter sends error correction information along with the actual signal so that should errors occur, the receiver can re-generate the bit stream.

FEC when used with QPSK modulation uses two forms of error correction. The first, called convolutional coding with the Viterbi algorithm code is quoted as a fraction, for example, 2/3. The fraction defines the amount of the symbol rate that's used for real data, with the remainder used error correction purposes.

After the convolutional error correction code has been removed and used as needed, a second error form of error correction is used called the Reed-Solomon code. This correction results in 188 bytes out for every 204 bytes coming in with the remainder used as parity bits to help correct any remaining errors. Additionally, the FEC scheme also uses interleaving of the data stream to prevent noise bursts from interrupting the flow of data in much the same way that CDs use it to prevent scratches from causing drop-outs.

Consider the following message:

This is a sample message

If interleaved, it might look like:

eTs haais mgi smeaesp l

Should an error occur and say wipe out the 'mgi' part of the message, the de-interleaved message will now read

This *s a sa*ple messsa*e

As a result, only single characters are missing from the message (shown here as asterix), rather than an entire word missing in the case of non-interleaved data.

As a final step, the QPSK symbols are scrambled to ensure that long runs of the same symbol value don't cause a lack of change in phase of the carrier. Since the QPSK demodulator obtains its signal clock from directly from the signal, there must be a large number of phase changes in order to re-generate the clock and of course scrambling results in this. Note: this form of scrambling is not the same as scrambling of the decoded signal.

Why use different SR/FEC values?

When people purchase time on a satellite, in effect they are primarily paying for the bandwidth. Therefore if a programmer wanted to transmit three video channels via a transponder, he would use less bandwidth than a service that transmitted six. However, the bandwidth of a transponder is finite and therefore an upper limit is placed on the SR (typically between 28 and 29 MS/s). By reducing the amount of FEC information sent along with the actual data, the number of channels can be increased. However, this then means that errors are harder to correct and that the down link stations must be able to receive a certain signal strength (i.e. use a certain size dish) in order to receive quality programming via the transponder.

In a nutshell I always remember the lower the 1st number, the more play you have for a stable signal. so 1/2 has more play than 5/6
 
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