GOES 16 GRB downlink vs GVAR
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I wasn't thinking about that in size.
I can get something setup for the files.I want to make sure we are on the same page here with the recorder. They give me two options for recording and it's TS or GS.
I'm guessing is GS since it's generic stream.
TS don't seem to concern us here from the research I did.
Let me know please.
I'm dumbfounded by that feed not giving a better result. Otherwise I'll wait till after you tweak the dish for anymore comments.
I even tried disabling the power saver functions on the usb hubs. The recorder will tell me a lot more about the stream as it has quite a lot of detail with it. I know one thing, I attempted to install the TBS IP program on the Win 7 machine so to see if it had the same outcome as the XP machine and it don't like it at all.
I get the blue screen of death every time I open it with the receiver connected to the computer.
The recorder is fine on Win 7 machine.
As you already know, no problems on the XP machine.
Yes, GS (generic stream).I wasn't thinking about that in size.
I want to make sure we are on the same page here with the recorder. They give me two options for recording and it's TS or GS.
I'm guessing is GS since it's generic stream...
Thanks Brett.
I have made a page since we have been talking and it has some of the images I have loaded here along with some of the NETCDF files.
The recording may be too big for that site but I can put up a link, I figured a good place to put a lot of this info.
You can find it here:
GRB BBF for view
I have made a page since we have been talking and it has some of the images I have loaded here along with some of the NETCDF files.
The recording may be too big for that site but I can put up a link, I figured a good place to put a lot of this info.
You can find it here:
GRB BBF for view
Ok, so wanted to mentioned that I made some small enclosures using aluminum tape for the LNAs I have, as we briefly discussed before, and I was able to get about 7dBm increase in the signal strength while at the same time allowing me to reclaim one LNA and and three filters. Definitely the metal enclosures I had were not environmentally friendly.
Now, this time I appeared to have been able to get a more stable streaming (few sync errors here are and there, but nothing preventing reception) for ~36hr before GRBStreamer lost the lock. I would typically reconnect the coax, but this time I let it be and checked back 30 min to 1hr later and found the GRBStreamer had regained the lock and was streaming once more. Interesting enough, the DVBLogReader that comes with the DD card drivers has a nice history showing losses and re acquisition of signals and it showed the following around when GRBStreamer stopped:
2/20/2018 10:44:07 AM DDTuner Device 240:10000: Signal lost DVB-S Tuner 1
Version = 2
Error = 00000000
LockStatus = 0
Strength = 33
* Strength = 37
* S/N = 81
* Quality = 61
* Offset = 651
2/20/2018 10:44:21 AM DDTuner Device 240:10000: Signal reacquire DVB-S Tuner 1
Version = 2
Error = 00000000
LockStatus = 5
Strength = 36
S/N = 75
Quality = 51
Offset = 708
Not, really sure what caused it to lose the signal with an 8.1 SNR for 14 seconds, but won't be surprised if I could have some local interference causing a bit of a havoc at times. I did noticed in the output above, that the signal strength did jumped to 33dBm, so this could have likely overloaded the receiver and/or LNA and caused the disconnect. I might try removing one more LNA and see if there's a difference.
N6BY, I hope you don't get the same issue as I am, but in a way, I kind of want you to experience it, so you can replicate it on your end LOL!!! Does GRBStreamer have a timer to check connection status and attempt a reconnection? I figured if it could have an option to specify (or hard code a time if you like) a "connection check" timer (in min or sec) that can be specified, then it might take care of finding sweet spots for multiple configurations/locations.
As a last note, waiting for a couple parts to move to the second phase, of trying to receive LHCP with the Canantenna via the splitting methods we discussed before. Hopefully, I won't have too much attenuation to be able to get both from the same antenna.
Now, this time I appeared to have been able to get a more stable streaming (few sync errors here are and there, but nothing preventing reception) for ~36hr before GRBStreamer lost the lock. I would typically reconnect the coax, but this time I let it be and checked back 30 min to 1hr later and found the GRBStreamer had regained the lock and was streaming once more. Interesting enough, the DVBLogReader that comes with the DD card drivers has a nice history showing losses and re acquisition of signals and it showed the following around when GRBStreamer stopped:
2/20/2018 10:44:07 AM DDTuner Device 240:10000: Signal lost DVB-S Tuner 1
Version = 2
Error = 00000000
LockStatus = 0
Strength = 33
* Strength = 37
* S/N = 81
* Quality = 61
* Offset = 651
2/20/2018 10:44:21 AM DDTuner Device 240:10000: Signal reacquire DVB-S Tuner 1
Version = 2
Error = 00000000
LockStatus = 5
Strength = 36
S/N = 75
Quality = 51
Offset = 708
Not, really sure what caused it to lose the signal with an 8.1 SNR for 14 seconds, but won't be surprised if I could have some local interference causing a bit of a havoc at times. I did noticed in the output above, that the signal strength did jumped to 33dBm, so this could have likely overloaded the receiver and/or LNA and caused the disconnect. I might try removing one more LNA and see if there's a difference.
N6BY, I hope you don't get the same issue as I am, but in a way, I kind of want you to experience it, so you can replicate it on your end LOL!!! Does GRBStreamer have a timer to check connection status and attempt a reconnection? I figured if it could have an option to specify (or hard code a time if you like) a "connection check" timer (in min or sec) that can be specified, then it might take care of finding sweet spots for multiple configurations/locations.
As a last note, waiting for a couple parts to move to the second phase, of trying to receive LHCP with the Canantenna via the splitting methods we discussed before. Hopefully, I won't have too much attenuation to be able to get both from the same antenna.
Besides local interference, the loss of connection could be a problem at the uplink side too.
All GRBStreamer does is send a command to lock the signal. Once locked it enables the 'Start Streaming' button. After that its all pretty much up to the card and device driver.
It's like watching TV. If the signal cuts out and you do nothing, it often comes back on its own.
But I have no way to test GRBStreamer now. I'm only getting about 4 dB with my cantenna and cannot lock the signal. I may have to wait for GOES-17
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How well you shield the electronics makes a difference.Definitely the metal enclosures I had were not environmentally friendly.
On my setup when I get there.. I will use feed through caps on my power leads to clean up/remove any AC on the DC power leads.
KWX something tells me that the sun may have caused that dropout. If I'm not wrong the sun at that time on the log should be in front of your dish.
If I recall it's about 11:40 here and the sun gets in the antenna.
Some small varying in signal level is not unexpected. I see NOAAPORT vary by a .2 .3 dB sometimes. Path flux and atmospheric, even satellite slight Xmitter power change.
Agree also with Brett that the link itself can have issues.
If you can afford to remove an LNA go ahead as you are well within the range of that receiver. You can always add it back if needed.
As for your last note of trying to get both, hope it works.
Brett, would you please post some pics of that cantenna feed here. I want to see it. It makes no sense that it's working that way.
Its the same one I posted earlier -- the 'Quaker cantenna'. I just added a probe, two equal length cables, and the 90 degree combiner.
Have you uploaded a generic stream dump from TBS Recorder so we can see why yours is getting sync errors?
I just don't understand why that feed is not working.
I want to do something about it..
I may contact you via email on more about this.
Answer: Nope, the temps haven't even made it to freezing since my last test I posted. Ice everywhere and more snow on the way.
I'm not messing with that until it warms up towards 40 and the wind isn't blowing as fast.
From the forecast maybe this weekend it will reach that temp. before another storm.
Tonight I adjusted the dish aim and feed distance and was able to bring the SNR up to 5.5. That's the best that the little can antenna is going to get here. Will see what it does when I re-aim it at GOES-17 in a few months.I just don't understand why that feed is not working.
I want to do something about it..
I may contact you via email on more about this....
Small update here on the amps I ordered from China on ebay.
They have all come in, not too bad on the shipping wait time.
Haven't tested them but they don't look cheaply built.
A least at the moment they look like good choices for this project.
As of now though I am sticking with what I'm testing before any changes are made.
Also for Brett, it's looking like sometime early in the week I can get those recordings as the weather here looks to finally let up. We have had freezing rain every other day now.
They have all come in, not too bad on the shipping wait time.
Haven't tested them but they don't look cheaply built.
A least at the moment they look like good choices for this project.
As of now though I am sticking with what I'm testing before any changes are made.
Also for Brett, it's looking like sometime early in the week I can get those recordings as the weather here looks to finally let up. We have had freezing rain every other day now.
Finally got those recordings.
They can be found here:
GRB recordings
I made some screenshots of each system of the recordings. It ID's the stream info.
Used the older choke ring for this try and gained a 1/2 dB C/N.
Though for the size of the recordings I have a feeling that this receiver won't work for this.
Otherwise we'll see what Brett has to say.
Screenshot of the Win XP TBS Recorder
Screenshot of the Win 10 TBS Recorder
They can be found here:
GRB recordings
I made some screenshots of each system of the recordings. It ID's the stream info.
Used the older choke ring for this try and gained a 1/2 dB C/N.
Though for the size of the recordings I have a feeling that this receiver won't work for this.
Otherwise we'll see what Brett has to say.
Screenshot of the Win XP TBS Recorder
Screenshot of the Win 10 TBS Recorder
I have analyzed both files and each has similar problems.
A valid BBFrame begins with the byte sequence (in hex) 71 00 00 00 E3 00. While there are numerous occurrences of that sequence present in both files, the distance between them (in bytes) is variable. They should all be 7274 bytes apart.
Instead, in the Windows 10 dump they are found 11328, 4112, 608, 2428, 7165 bytes apart. The XP dump is similar.
My best guess at the cause of this is that the signal quality is too low and the TBS5927 is dropping data due to errors.
Thanks Brett,
I uploaded another recording at the same location, Take a look at it and tell me what you see.
I can't get the quality over a level of 35.
I uploaded another recording at the same location, Take a look at it and tell me what you see.
I can't get the quality over a level of 35.
I examined it in a hex editor and I'm seeing the same thing as yesterday. The BBFrame headers are spaced random distances apart. None of the ones I checked were 7274 bytes apart (but I only checked the first 6).
All of the above BBFrames would show up as sync errors in GRBStreamer. So it would be your best tool to evaluate signal quality.
Thanks again Brett,
I did get the quality level up to 39 but that was all.
The first recordings were done with the Nooelec filter/LNA and the UTRLA LNA in the setup.
I was thinking that maybe I might be over driving the output so I removed the Nooelec filter/LNA and dropped the signal C/N down to 7.5 when I made the last recording.
Since you were seeing the BBF's headers often I should have been able to see some kind of good BBF's.
Since I have had a signal level = to or better then what we have been posting here I should have had some good data.
My conclusion is the TBS5927 is not capable of decoding the GSE data due to firmware and or driver flaws. It can decode MPE though. I bought the receiver in thoughts that it would work for this since it was described to and also KWX's TBS5925 works for it.
But due to this outcome the project is on hold indefinitely.
The cost only goes up from here for me, so I will have to do much more research on the next move.
I will be here to answer any questions that you may have.
I look forward to see how everyone's setup goes.
I did get the quality level up to 39 but that was all.
The first recordings were done with the Nooelec filter/LNA and the UTRLA LNA in the setup.
I was thinking that maybe I might be over driving the output so I removed the Nooelec filter/LNA and dropped the signal C/N down to 7.5 when I made the last recording.
Since you were seeing the BBF's headers often I should have been able to see some kind of good BBF's.
Since I have had a signal level = to or better then what we have been posting here I should have had some good data.
My conclusion is the TBS5927 is not capable of decoding the GSE data due to firmware and or driver flaws. It can decode MPE though. I bought the receiver in thoughts that it would work for this since it was described to and also KWX's TBS5925 works for it.
But due to this outcome the project is on hold indefinitely.
The cost only goes up from here for me, so I will have to do much more research on the next move.
I will be here to answer any questions that you may have.
I look forward to see how everyone's setup goes.
