Smallest EMWIN antenna

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External power. I have it hooked to a wall-wart. LNA needs 5vdc internally but it has resistors to allow the use of a 12.8vdc PSU (resistors drop the voltage to 5vdc) Believe me, I have played and played with different power adapters. I even put a ferrite core on the power input.
 
Still waiting for my LNA4ALL.... anyone ordered one before? how long on shipping???

Trip - KT4WO
 
ok....cool beans Then maybe next week I can start decoding EMWIN!!!! whoooo hoooo!!
LOL

Tnx all.

Trip - KT4WO
 
So far the only person with access to the decoder Joe wrote is outatyme. I imagine he'll want to get it all polished up and ready for end users before publicly releasing it.
 
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I'm still waiting on receive system improvements to conduct further testing. Viterbi error is high (400-600) and there are frequent loss of sync events It looks like things will be good with a new LNA and band pass filter but I am a poor bastard.
 
I have been monitoring this thread.
I will give some advice to the person and anyone else that is having problems with getting the EMWIN signal.
Your dish needs to be as parabolic as possible, you can't have big deformations in it as that will effect your signal quality. Make shure that you're at your dish's focus, if your off here you can lose 2 to 3 dB is signal and in your case that is critical.
Mount your amp as close as possible to the antenna, coax = loss at 1.6Ghz. Make shure that all your amps and parts are compatible with the frequency of EMWIN, Certain parts, amps may not be optimum for this use. Especially since your are just at the threshold for signal.
Do not use different types (impedances) of coax, this is a place that can cause mismatch and loss. Most systems are 50 Ohms. Unless noted. Use proper connectors.
One way to check to see if you have an interference near by is move the antenna off the satellite sweep it a bit and watch in your display (assuming using SDR or similar to view signal) for anything that shows up that is not just noise, also if the noise floor rises unexpectedly. The noise floor will with the amp as it raises the noise floor as it amps the signal and this is normal.
A 1.2 meter dish should give about 22 dB of gain at a 40% Efficiency.
It sounds like your well on your way as your can see something of a signal just keep tweaking.
Since you were having trouble looking for the satellite I have included some pics of the GOES 13 on a spectrum analyzer with my 8' dish.

GVAR Emwin 300kHz bandwidth.JPG - Here is GOES 13 at 300kHz bandwith, From right to left EMWIN signal, GVAR signal (the large wide one)
Also keep your bandwidth filter if possible near 30kHz on your SDR as the EMWIN signal is around 20kHz wide, as that picture shows the wider filter bandwidth lets more noise in.

GVAR Emwin 30kHz bandwith.JPG - Same view but the bandwidth has been narrowed to 30Khz. Note how the EMWIN signal sicks up like a sore thumb now. (display is centered on the GVAR signal)

Emwin Lrit.JPG - Same bandwidth setting but form Left to right the EMWIN signal and looks like noise but that is the LRIT signal.

Emwin 30KHz bandwidth.JPG - Focused on the EMWIN signal, I think it 10kHz per division. I didn't look at the setting when I was taking that picture.
Your signal on the 1 meter dish will look much weaker but hope this gives you some idea or anybody else trying this.

I have a RTL-SDR USB Tuner Receiver R820T+2832U Radio on the way and since reading this forum I do want to try it on my EMWIN signal. If a receiver like this can be used to receive EMWIN this would make it the most cheap setup that is around.
My setup is an Copper homemade horn for 1.6Ghz a low nose DEMI amp ULTRALNA, Wilmanco downconverter and the EMWIN 2 receiver.
I also receive the GVAR signal and NOAAPORT as well on 2 other Dishes.

GVAR Emwin 300kHz bandwith.JPG
GVAR Emwin  30kHz bandwith.JPG
Emwin Lrit.JPG
Emwin 30KHz bandwith.JPG
Tim KC0HWG
 
Thanks for the info Tim.

I am curious as to what the minimum dish size is to receive GVAR. I can see the LRIT and GVAR signals with this little 1 meter dish. but no software to process them.

It is unknown if the signal quality would be good enough as well.

Joe Steinmetz (The creator of the USA-SATCOM EMWIN-N demodulator) says it won't be possible to receive LRIT with such a small dish.
I am inclined to believe him but still think it would be worth a shot to try.
 
GVAR can be got with a 10' dish, must be set up properly. Though most use a 12' dish (such as me) for some margin. I will not get in to much more discussion on GVAR on this forum, I can start a new forum for that if there is more interest. I want to keep this EMWIN.
GVAR is not for the faint of heart, If you cringe over spending on EMWIN then you'll have to clean your pants on GVAR. Simply said it's expensive.
Don't know much about LRIT, so can't help you there much. I'd listen to Joe on that.
Also outatyme I have made you a wav file of the EMWIN audio. The file is about 45M is size so you will need to tell me where to send it. You will have to use another device and send the audio to the line in jack of the computer that has the decoding software due to the demodulator will not see the signal unless it's at the line in jack. Anybody else have any suggestions feel free to add them. At least that was my experience when trying to decode the audio file. I had no luck just playing it on my machine that had the decoder software.
Also the decoder that WXmessage has, which is the software that the EMWIN team made has an adapter that you can download to see if you have a front end signal. If you want a screen pic of what I am talking about I can take one just ask.
Also and very importantly the software demodulator may have to be tuned to frequency to see the EMWIN signal. It sweeps in 7000Hz segments. If the signal is not in that segment it won't find it. That's under the configuration tab.
The guys that make the EMWIN2 receiver told me that one.

Tim KC0HWG
 
Hope that will help you outatyme
For anybody wanting that file of the EMWIN audio it is here:
http://www.filedropper.com/emwinsample

doubleohwhatever I called Wilmanco and unfortunately they don't make that anymore. They only make the frequency multipliers, that's sad. Their stuff was expensive but it's really good.
There were no part #'s due that the customer would tell them what they wanted for Input and output frequencies. Such as one of the units I have here
Model WDC 1687.5 - 70
I have no idea where you could get a block downconverter now. Guess you have to search the internet if one is needed. I can tell you this that those about 10 years ago cost near $1,000.00 for one but they were worth every penny as they have great stability.

It's L band that GOES uses.
Norsat, Raditek, Satcom make block downconverters. For L Band?
I just did a quick search.
Quorum Communications makes one for the L band.

Timothy KC0HWG
 
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Thanks so much Tim - I believe you about the 10' dish for GVAR...
I can just barely see the GVAR signal at 1685.7 Mhz.
Seems like lots more Gain would be needed for GVAR!.

I will take the sample data you sent me and see what I can do with it.

What I can currently see with my 1-meter grid parabolic dish:
I can see LRIT at 1691.0 Mhz - It looks like there might be enough signal to demodulate it if I had the software.
I can see EMWIN-N and can demodulate it using USA-SATCOM (Joe's) EMWIN-N Demodulator. - However I have a broadband noise problem.
I can see DCPR at 1694.5 Mhz - but again, no software to process it.
I can see MDL at 1681.478 Mhz - Same deal, no software to process it.
I can see SARSAT (GOES Search and rescue) at 1544.5 Mhz - No software to process it
and I can see GOES sensor data at 1676.0 Mhz. - No software to process it.

Signal gain (dish size) might not be adequate for several of these signals as well.


Images of various GOES Signals I can see:

emwin_eleven.png
RIGHT-TO-LEFT: DCPR, EMWIN-N, LRIT


emwin_twelve.png
GVAR


goes_mdl.png
MDL


goes_sar.png
SAR (Search And Rescue)

goes_sensor.png
SENSOR Data



Tim, it looks like GVAR is going to be replaced on the GOES-R satellite with something called GRB and new equipment will be needed in the next 5 or so years :-(
http://www.eumetsat.int/website/wcm...testReleased&Rendition=Web&dDocName=CWPT_1456
 
it looks like GVAR is going to be replaced on the GOES-R satellite with something called GRB and new equipment will be needed in the next 5 or so years
Odds are it'll be faster than five years. GOES-R should become active as east or west by the end of 2017. That will only leave you with one GVAR capable satellite. GOES-S is supposed to be launched, done with checkouts and in storage by the end of 2017 as well. GOES-S isn't scheduled to become active until early to mid 2020. However, that transition could happen sooner if any issues arise with the older satellites.
 
outatyme
I told you this and had to go back a re read the forum again:

"You will have to use another device and send the audio to the line in jack of the computer that has the decoding software due to the demodulator will not see the signal unless it's at the line in jack. Anybody else have any suggestions feel free to add them. At least that was my experience when trying to decode the audio file. I had no luck just playing it on my machine that had the decoder software."

I missed that Joe Steinmetz USA Satcom had a demodulator that was working with the SDR. I was thinking of the audio demodulator that the EMWIN team made, apologies for that.
I am interested in that demodulator that Joe Steinmetz makes and if it will work with HDSDR + when a copy is available.

A 10' dish is adequate for GVAR as long as nothing interferes or causes degradation of the signal it will be error free, Does also depend on location from GOES.
Ya the old GVAR format will be replaced with something called GRB, However this could be good for all of us as the GRB will use a DVB-S2 transport layer meaning the a DVB-S2 receiver will be able to receive the GRB signal though it will still require a 12' dish. All that will be needed is to decode the frames coming out of the DVB receiver into files of Level1B format.
Then an interface will be needed to display the images. There is one out there now that can display that format. I don't think that it would super hard to write the code to decode the GRB frames. Somewhere out there is code for linux for just that for free download. For the testing purposes it was written. I think the new Satellite is supposed to be launched the June? I think.
EMWIN will also be upgrading as well with the series of satellites in speed.
From what I last knew the LRIT, EMWIN data streams are to be combined into one. But that was last I knew.
doubleohwhatever you may be very right, the GOES east sounder is currently down and doesn't look to be coming back anytime. It had a filter wheel motor failure about 1 and a half months ago.

Timothy KC0HWG
 
I wanted to get new pictures on my downlink as that one I posted earlier were not correct though they looked somewhat correct. This is the proper GOES Spectrum. I did something kinda stupid :rolleyes:. It has been some time since I messed with this system so I forgot a simple item when I took those last pictures.
That Wilamnco downconverter is biased through the coax, That means it gets it's power through the coax. Needless to say they don't work with out power going to them. So here are the proper pics of the GOES EAST spectrum that will mach up much better with outatyme's pictures. Discard the previous pictures, Man I feel dumb right now.:oldfrown
Again 8' dish peaked on GOES.

GOES EAST Spectrum 300 kHz.JPG - This is what you will see when acquiring the GOES spacecraft. From left to right DCPR, EMWIN, LRIT, GVAR, telemetry.

EMWIN_LRIT_GVAR 300 kHz.JPG - Again from left to right EMWIN, LRIT, GVAR. Note on the GVAR signal that the is s knobs on top of it, when these are seen in wideband the GVAR signal is able to be decoded. Here it is somewhat in the noise. GVAR is around 10dB above noise floor in pic.

EMWIN_LRIT_GVAR 30kHz.JPG - Same view but with 30 kHz bandwith filter.

DCPR_EMWIN_LRIT.JPG - 30 kHz bandwith viewing DCPR, EMWIN , LRIT. EMWIN, LRIT 8 dB above noise floor.

EMWIN 30 kHz.JPG - 30 kHz bandwith looking a EMWIN. Signal is 8 to 8 1/2" dB above noise.
GOES EAST Spectrum 300 kHz.JPG
EMWIN_LRIT_GVAR 300 kHz.JPG
EMWIN_LRIT_GVAR 30kHz.JPG
DCPR_EMWIN_LRIT.JPG
EMWIN 30 kHz.JPG

Timothy KC0HWG
 
I'm honestly just about to give up on the smaller grid antenna. No matter what I do, this is the best I can get:
 

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doubleoh, what setup do you have? I see you are tuned to 139.2 Mhz. This must imply you are using a downconverter?
you have some signal losses somewhere along the line.


What sort of LNA are you using?
what type of cabling?

an overview of your receive setup would help in troubleshooting things.
 
Here's the setup I was using with that last screenshot:

Dish - http://goo.gl/sg3L2C
N to SMA Adapter
LNA - http://goo.gl/KUzXtA
SMA to BNC adapter
Downconverter - http://www.hsmicrowave.com/page46.html
BNC to N adapter
Coax - 3ft of LMR200
N to SMA adapter
SDR - Airplay


This is the setup I'm using at the moment

Dish
N to SMA adapter
LNA
SMA to N adapter
Coax - 3ft of LMR200
N to SMA adapter
SDR - Airplay

I've attached a screenshot of what this setup produces in SDR# as well as a screenshot of what I get with SDR-Console and the decoder running.

I have to be either overlooking something or doing something wrong. All I know is that this driving me nuts not being able to get this to work.
 

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