97w C band
- Thread starter zeljko
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el bandido
TNAP-Images
That footprint map says I need a 1.3 meter dish which is not accurate at all for this 16APSK mux. I have a 2.3 meter dish that gets about 6db snr on this mux. it takes a little over 10 db snr just for this mux to open. You can expect to need a dish 3 meters or larger.
el bandido
TNAP-Images
You could probably check 10 OpenBox receivers and get different results out of at least two of them.
Receivers and their tuners generate noise. A receiver or tuner that generates less noise will be able to receive a weak signal better, but no receiver or tuner no matter how good or bad it is will change the minimum snr requirement for a given modulation and FEC (16APSK 3/4FEC).
I think the strongest transponder I get on 97W is 3940H 30000SR.
Receivers and their tuners generate noise. A receiver or tuner that generates less noise will be able to receive a weak signal better, but no receiver or tuner no matter how good or bad it is will change the minimum snr requirement for a given modulation and FEC (16APSK 3/4FEC).
I think the strongest transponder I get on 97W is 3940H 30000SR.
el bandido
TNAP-Images
0% Q = ?
50% Q = ?
75%Q = ?
100% Q = ?
The point I am trying to make is those Q numbers mean absolutely nothing. Q is a measure of the total received signal, including the noise. To make matters worse, there are no set values for what a certain Q percentage is supposed to equal. One box may have a 50% Q while another may show 80% Q on the exact same signal. All of our signal measuring in consumer fta is flawed, but I think the Q signal is probably the worst.
Any slight change in the upper atmosphere will cause you to lose or receive the 16APSK signal. It is that simple.
You are on the very fringe of reception at your location. About the only way to improve what you have is to get a bigger dish antenna. Or maybe some professional lnbs that actually reduce noise. A bigger dish would be the best option. A thousand dollar lnb may help a little bit or it my not help at all.
50% Q = ?
75%Q = ?
100% Q = ?
The point I am trying to make is those Q numbers mean absolutely nothing. Q is a measure of the total received signal, including the noise. To make matters worse, there are no set values for what a certain Q percentage is supposed to equal. One box may have a 50% Q while another may show 80% Q on the exact same signal. All of our signal measuring in consumer fta is flawed, but I think the Q signal is probably the worst.
Any slight change in the upper atmosphere will cause you to lose or receive the 16APSK signal. It is that simple.
You are on the very fringe of reception at your location. About the only way to improve what you have is to get a bigger dish antenna. Or maybe some professional lnbs that actually reduce noise. A bigger dish would be the best option. A thousand dollar lnb may help a little bit or it my not help at all.
rrob311
Administrator
This one cut out on me yesterday and it was cloudy. I measured 11db or so with my DR HD receiver and it wouldn't hold. That was after adjusting the elevation on my dish. Today I am getting 11-12 and it is working fairly well. I still haven't messed with the lnbf and I am using a B1SAT stack. It is sunny and above freezing right now so I may try one of my other new lnbf to try out.
mountaineer
Legit VIP
It did that for everybody that I know of yesterday. I think it was on their end not ours. Seems they work on their uplink on saturdays and yesterday the work was especially painful for us on the receiving side. just my opinion
mountaineer
Legit VIP
I normally get around 12.3 db's...yesterday about the same down to about 12....today about 11.7 but good picture...that is why I think it is the uplink. Many others with better systems than mine reported it as well. Hope that helps.
el bandido
TNAP-Images
You can expect to have pixelation or complete lass of signal around 10.2-10.5 db SNR providing this value is being calculated correctly by the receiver.. You can bump the dish a bit and see the db snr level where loss of signal occurs.
Single feed lnbs will usually have a db or two advantage over a dual or quad lnb. I usually get between 11.5 and `12.5 db snr using a Pauxis dual lnb. I would expect to get another db or two more in snr if I installed some professional lnbs. The diameter of my dish is 3.6 meters or almost 12 feet.
Last edited:
el bandido
TNAP-Images
Lots of things to think about:
LNB's work over a wide range of frequencies. LNB A may do better at 3980 MHz than LNB B. But LNB may do better at 3890 MHz tan lnb A.
Tuner in receiver A may work better at certain frequencies, but perform worse at other frequencies than the Tuner in receiver B.
The idea is to decrease the noise Floor which almost always increases the satellite signal.
Large coax has tendencies to decrease noise when compared to small coax. (This is a very small amount but every little decrease in noise helps a bit.)
Cheap lnbs are not made using quality parts. Cheap lnbs are not made using strict guidelines. Cheap lnbs usually perform fairly well on most fta signals.
16 APSK requires a tighter skew than DVB-S, DVB-S2, or 8psk. Fine tuning lnb skew should usually be done using the 16apsk signal.
Setting the depth of the lnb in the scaler ring should also be done on the 16apsk transponder when possible. The markings on the side of the lnb for depth may not be 100% accurate on cheap lnbs.
ALL adjustments for a motorized dsh should be done at center of the arc ( due south satellite) whenever possible. This applies to any band and any dish size.
After fine tuning linear lnbs, they may be rotated 180 degrees which may or may not increase the signal. I have picked up over 1 db in snr at times by doing this.
Receivers that only display signal quality readings should be avoided when fine tuning satellite equipment. Most quality readings only show a sum of the noise + the satellite signal strength. It is possible to raise the noise and raise the signal quality reading!
Signal Accuracy using a receiver that reads signal to noise ratio (snr) may give incorrect or inflated values but snr readings are usually much better than the signal quality reading.
Know where the signal should drop or the satellite tv picture should pixelate at and verify that the snr in db is close to or equal to that amount as a crude calibration test.
Black satellite antennas and black satellite antenna parts should be avoided. The color black usually looks better, but it also attracts heat. LNBs and other satellite antenna parts usually work better in cooler temperatures. Commercial satellite antennas are almost always white in color for good reasons.
LNB's work over a wide range of frequencies. LNB A may do better at 3980 MHz than LNB B. But LNB may do better at 3890 MHz tan lnb A.
Tuner in receiver A may work better at certain frequencies, but perform worse at other frequencies than the Tuner in receiver B.
The idea is to decrease the noise Floor which almost always increases the satellite signal.
Large coax has tendencies to decrease noise when compared to small coax. (This is a very small amount but every little decrease in noise helps a bit.)
Cheap lnbs are not made using quality parts. Cheap lnbs are not made using strict guidelines. Cheap lnbs usually perform fairly well on most fta signals.
16 APSK requires a tighter skew than DVB-S, DVB-S2, or 8psk. Fine tuning lnb skew should usually be done using the 16apsk signal.
Setting the depth of the lnb in the scaler ring should also be done on the 16apsk transponder when possible. The markings on the side of the lnb for depth may not be 100% accurate on cheap lnbs.
ALL adjustments for a motorized dsh should be done at center of the arc ( due south satellite) whenever possible. This applies to any band and any dish size.
After fine tuning linear lnbs, they may be rotated 180 degrees which may or may not increase the signal. I have picked up over 1 db in snr at times by doing this.
Receivers that only display signal quality readings should be avoided when fine tuning satellite equipment. Most quality readings only show a sum of the noise + the satellite signal strength. It is possible to raise the noise and raise the signal quality reading!
Signal Accuracy using a receiver that reads signal to noise ratio (snr) may give incorrect or inflated values but snr readings are usually much better than the signal quality reading.
Know where the signal should drop or the satellite tv picture should pixelate at and verify that the snr in db is close to or equal to that amount as a crude calibration test.
Black satellite antennas and black satellite antenna parts should be avoided. The color black usually looks better, but it also attracts heat. LNBs and other satellite antenna parts usually work better in cooler temperatures. Commercial satellite antennas are almost always white in color for good reasons.