GOES 16 GRB downlink vs GVAR

N6BY

N6BY

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Be carefull on Amazon, got a clone 6303 that would not switch polarity.
Make that a 6903.
The seller used to be 'dvbforfun', but I see that some other company is selling in their place on Amazon.

'dvbforfun' is still on eBay and I know that they are TBS. So it sounds like we need to use eBay now instead of Amazon.
 
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ghulands

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May 4, 2022
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Oregon
Hi,
I have been capturing the HRIT signal using goestools to decode and process it. I wanted to give the GRB signal a go and have found a 12ft Precision Parabolics E200 dish. I'm not sure of the specs as I can't find anything online, but looks like it might be a C Band one. Could someone confirm if this would work?
Thanks in advance.


Dish
 
N6BY

N6BY

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Lifetime Supporter
Mar 1, 2006
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Hi,
I have been capturing the HRIT signal using goestools to decode and process it. I wanted to give the GRB signal a go and have found a 12ft Precision Parabolics E200 dish. I'm not sure of the specs as I can't find anything online, but looks like it might be a C Band one. Could someone confirm if this would work?

The dish is big enough but you would need a new feed for GRB. The C Band feed won't work. GRB uses L-Band with dual circular polarity. Half of the data is RHCP (right hand circular polarity) and the other half is LHCP. For GRB, those polarities share the same frequency of 1686.6 MHz.

You could either build your own septum feed as described in this thread or try to buy a different type using a can and a custom designed splitter/combiner circuit made by Ed Murashie at Pro Engineered Solutions. I have tried both and I get much better results with Ed's feed.

The reason I said (in the above paragraph) "try to buy" Ed's feed is that he is only making them in small batches at a time. He is busy and I don't know if or when he will have time to build more. So I would recommend contacting him through his website and see what his schedule is.

The other critical resource is a TBS6903 DVB receiver. They are still available on eBay and Amazon. If you pay $290 on Amazon you can get one overnight via Amazon Prime. Otherwise they ship from China. I don't know how long it will take as many parts of China are locked down right now due to COVID. Also, it was reported a little earlier in this thread that someone buying through Amazon got a defective "clone". Maybe that was an isolated instance or he just happened to get a defective unit?

Be sure not to get a TBS6903X. This is because the "X" version uses a different chipset that I have not yet been able to get working well with GRB. I'm seeing a high packet error rate. Could be that is because of the different chipset or that I am not programming it correctly? It is an extremely complex chip used in the TBS6903X,

As for software, you can either use CSPP Geo from the University of Wisconsin / Madison which is a complex Linux program that is very CPU intensive or GRB Imager from me for $100 plus shipping for the Program CD-ROM.

If you go with CSPP Geo you'll need my GRB Streamer Program to read the GRB data from the TBS6903 DVB card and stream it via ethernet (UDP protocol) to CSPP Geo for processing. That would involve a Windows PC running GRB Streamer and a Linux PC with 12 cores and about 32 GB of RAM that are necessary to run CSPP Geo.

GRB Imager requires a Windows 7 or 10 PC with a 4 core CPU and 8 GB of RAM (or more).

So GRB is more expensive to setup than HRIT, but the result is much higher resolution images and more of them.

Brett
 
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ghulands

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May 4, 2022
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0
Oregon
Hi Brett,
Thanks for all the great info. Did you ever make any headway with the streamer running on linux? I was thinking for my situation that I would put a small SBC (a RockPro64 as it has a PCIe 4x slot looks like the best candidate) close to the dish and power it with PoE so I can reduce any cable losses, and then have the big machine somewhere else in my network. I read in a later post that you removed the streaming functionality from GRB Imager, but just wondering if it can still receive a stream from udp?

I could only see the TBS6903X on amazon last night, so I think i'll go the eBay route or direct from tbs. I'm guessing dvbforfun on eBay is just TBS itself.
 
N6BY

N6BY

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Roseville, CA 121W
Hi Brett,
Thanks for all the great info. Did you ever make any headway with the streamer running on linux? I was thinking for my situation that I would put a small SBC (a RockPro64 as it has a PCIe 4x slot looks like the best candidate) close to the dish and power it with PoE so I can reduce any cable losses, and then have the big machine somewhere else in my network. I read in a later post that you removed the streaming functionality from GRB Imager, but just wondering if it can still receive a stream from udp?

I could only see the TBS6903X on amazon last night, so I think i'll go the eBay route or direct from tbs. I'm guessing dvbforfun on eBay is just TBS itself.

TBS 6903 cards are still available on Amazon. When you search you have to put a space between "TBS" and "6903" -- Amazon product
View: https://www.amazon.com/TBS-Professional-Satellite-Demodulator-Broadcasted/dp/B01LVYWG50/ref=sr_1_1?crid=2AEKUFGB18HYW&keywords=tbs+6903&qid=1651786372&sprefix=tbs+6903%2Caps%2C136&sr=8-1


I have not made a Linux version of GRB Streamer.

Back when I tried it, GRB Imager did not reliably receive a UDP stream, so I took out that capability. I think it has to do with the overhead of running on Windows, and UDP packets get discarded before they have a chance to reach my program.
 
D

DarrylZ

Member
Hello,

Installed the TBS6903 card into a Win10 computer that has no other programs just GRB Streamer.

I get the message , after clicking the icon , “ No DVB found. Unable to continue”..

Is there any other software needed to activate this card ?

Thanks for any and all help.

Darryl Zimmer
 
N6BY

N6BY

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Lifetime Supporter
Mar 1, 2006
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2,370
Roseville, CA 121W
Hello,

Installed the TBS6903 card into a Win10 computer that has no other programs just GRB Streamer.

I get the message , after clicking the icon , “ No DVB found. Unable to continue”..

Is there any other software needed to activate this card ?

Thanks for any and all help.

Darryl Zimmer
Did you install the TBS6903 device driver? You may download it at the following URL: TBS 6903 Driver
 
D

DarrylZ

Member
Hello All,

Have GRB Streamer 2.11 operational..

Issues I had dealt with Digital Signature and W10. Defeated the Digital Signature an all is good now.

Also went to the TBS tuner web page and down loaded the W10 drivers.. Thanks Brett..

Looks like all that is left is the following : I have the coax installed on the bottom “F” connector , tuner 0..

I am seeing : Not Locked —— SNR = 1.42 to 2.30.. S=48. Q=0….

I see : “0” on sync error , circuit error and Frames Received..

Is the SNR a good number to have.. ?

What do I need to do to get : Frames Received, Start Streaming to function.

Thanks for any and all help, Darryl. Z.
 
D

DarrylZ

Member
PM sent. To initiate a "conversation" (PM) click on the user name in the Avatar and a box opens with options. One is for conversations.
J
Hello All,

Have GRB Streamer 2.11 operational..

Issues I had dealt with Digital Signature and W10. Defeated the Digital Signature an all is good now.

Also went to the TBS tuner web page and down loaded the W10 drivers.. Thanks Brett..

Looks like all that is left is the following : I have the coax installed on the bottom “F” connector , tuner 0..

I am seeing : Not Locked —— SNR = 1.42 to 2.30.. S=48. Q=0….

I see : “0” on sync error , circuit error and Frames Received..

Is the SNR a good number to have.. ?

What do I need to do to get : Frames Received, Start Streaming to function.

Thanks for any and all help, Darryl. Z.
 
N6BY

N6BY

Geek
Lifetime Supporter
Mar 1, 2006
2,674
2,370
Roseville, CA 121W
Hello All,

Have GRB Streamer 2.11 operational..

Issues I had dealt with Digital Signature and W10. Defeated the Digital Signature an all is good now.

Also went to the TBS tuner web page and down loaded the W10 drivers.. Thanks Brett..

Looks like all that is left is the following : I have the coax installed on the bottom “F” connector , tuner 0..

I am seeing : Not Locked —— SNR = 1.42 to 2.30.. S=48. Q=0….

I see : “0” on sync error , circuit error and Frames Received..

Is the SNR a good number to have.. ?

What do I need to do to get : Frames Received, Start Streaming to function.

Thanks for any and all help, Darryl. Z.
1.42 to 2.30 is too low. You need at least 7 to lock the frequencies and receive GRB.

As for the polarity switching polarity issue from post #681 - it doesn't matter since you are not using voltage to switch polarities. You should have one separate line of coax from each of the two outputs on your dish feed. Each line should go into a separate tuner in the TBS6903.

I need to ask you some questions to figure out why your SNR is too low.

What is the size of your dish? What type of feed are you using? Ed Murashie's feed or something else?

If you could post a photo of your dish and feed it might help.
 

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