Hey guys. Anyone getting g16 11787/3979? It's supposed to be a CBS wild feed (yes its on lyngsat) in use right now. There are other wildfeeds with the same parameters coming in great on g16 but this one is really flaky for me recently.
Anyone getting g16 11787/3979?
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I have no idea specifically with respect to this particular transponder, however.....
Those 3979 SNG transmissions are extremely variable, except for a few semi-permanent ones from DC and NYC. Many of them are from trucks or from different stations feeding back to network, etc, and they all seem to be very variable in signal strength, sometimes very strong, other times very weak. Plus they are often so close together that many receivers will try to lock onto an adjacent signal when you tell it to tune in on one of the signals. I've seen times when it depended upon whether I was trying channels from high freq-->low vs low freq-->high, with respect to which channels would lock in. And when you do lock in one of them off freq, the reception sometimes is deteriorated.
Anyway, it's not unusual for any of these channels to be flaky at times, because one time it might be a low power satellite truck poorly aimed, in bad weather, and another time it might be a higher power dish permanently aimed on top of a station, etc.
Since I'm pretty new at this stuff, is the symbol rate reflective of the "width" of the signal and impact the chance of hitting it right? Or is themajor issue with these that the sources are different everytime so its dependent on if the uplink is dead-on? For example that main "Newspath" feed is always very strong (60%+) and that presumably is a fixed, high power uplink. It has a different sr then 3979: 14321 I think.
Yeah, the SR is reflective of the width and bandwidth of the signal. a 3979 signal is close to that 3979 KHz wide at half height. The wider the signal or higher the SR, the more data that it can carry, and or the higher the quality of the signal. The 14.321 has not only a SD video channel, but also an IP/DVB internet style data stream, so it requires more bandwidth.
To illustrate the different "signal widths" compared to SR values, I just did a scan with my really beat up orbitron dish (so it isn't very high quality).
I've labeled a few of the peaks. For example, look at the one at 11860. This is a very broad peak with a 30,000 SR. It's one of those Hughesnet type internet data transponders. Then look at the 11771 peak. It's the Newspath signal, with sort of an intermediate width. (my program tries to estimate the width, but isn't exact). You can see your 11787 peak, but it is very weak. You can also see the 11885 DC-PATH signal, which is quite strong, but also notice how narrow it and the weak 11787 peak are.
Anyway, not a real clean spectrum, but it demonstrates how SR manifests itself as signal width.
I've labeled a few of the peaks. For example, look at the one at 11860. This is a very broad peak with a 30,000 SR. It's one of those Hughesnet type internet data transponders. Then look at the 11771 peak. It's the Newspath signal, with sort of an intermediate width. (my program tries to estimate the width, but isn't exact). You can see your 11787 peak, but it is very weak. You can also see the 11885 DC-PATH signal, which is quite strong, but also notice how narrow it and the weak 11787 peak are.
Anyway, not a real clean spectrum, but it demonstrates how SR manifests itself as signal width.
It's done with a PC card receiver, ie a Broadlogic 1030 . You can occasionally find them on ebay. I got mine for about $35 . Once you have the card, there is a program called blscan.exe , that will scan through the sat band, and give you a text file of freq and signal strength. I wrote a short VB program that turns that file into a spectrum, and it allows you to drag from one side of a peak to the other and it gives you a frequency and tries to estimate the SR. The SR isn't very good, but the freq is usually within 1 mhz.
bjblscan
This isn't to be confused with the so called BLSA, which is a real time spectrum analyzer, which I think only works on the Broadlogic 2030. This one takes about 8 minutes or so per scan, and it only works on the 1030.
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