SNR -SDR# good/OuternetInABox bad

Originally started out with Desktop Computer/Windows 10. Added the Outernet Patch Antenna, LNA and Dongle. I had to go outside to get a clear shot to the Sat. I get a very good signal SNR 18-20 regularly. I start up the software R2 and see SNR at about 1.2 and going down into negative and back and remains that way. I switched to the RTL-SDR.com dongle and no change. SNR good on SDR# 17-20. Start up the OuternetINABox software and it’s about the same as Outernet dongle. I’ve tried the cooling down thingy and no change. Any ideas would be appreciated. Thanks for all you have done.

When you say SNR of 18, do you mean that is what you are seeing in SDR#? Or did you see that high of SNR in a previous version of Outernet in a Box?

The 18 refers to the SDR#. I tried the previous version with about the same results. Once it goes negative it doesn’t get any better. Thanks.

I’m sorry I wasn’t very clear about my problem. I used SDR# to locate the and tweak the satellite. I get a good SNR and does vary slightly during the day on 98W. Then went to the software OuternetInABox to see if I could connect and that is when I realized it wasn’t going to work. I have the LNA at the antenna (patch) and then 20 feet of RG6 to the dongle and then about 3 feet of USB cable to the computer. I have replaced the Outernet dongle with the RTL-SDR.com dongle and do not see any real difference as far as SNR is concerned. Just searching, with the SNR going negative any positive but not getting close to what it takes to lock on. thanks.

Can you try without the 20 feet of RG6?

Yes, that’s the way I started out and didn’t make any difference as far as the SNR is concerned. I have tried a number of things with both the OuternetInABox and SDR#. Last night I revisited the heat thing and sometimes it does start out as 1.8 to 2.0 SNR but quickly goes negative. An Ice Block under it made little difference. Probably none as best I can tell. The antenna and Lna are really doing the job. Very nice as far as the signal is concerned 18-20 on SDR# I retried the RTL-SDR.com dongle. Still same good signal it just doesn’t work with OuternetInABox. SNR is no different. I did add a FM Trap between Antenna and LNA. No help as far as OuternetInABox SNR is concerned. Thanks for your reply!

What version of OIAB are you using? Is it Release 2?
https://archive.outernet.is/images/OuternetInABox/

Yes, Release 2. Thank you.

I’m scratching my head. Although I mostly use CHIP, I have tested OIAB across all three types of hosts. What is your host machine?

SDR# is a useful tool for tuning into a satellite but the SNR value it offers is only an estimate and not very accurate in my opinion. To see for yourself, slide the Zoom slider up in SDR# and watch the SNR go up.

Are you using rg6 cable rate for use with GHz signals or is it old cable tv line? Even if it’s the good stuff you will have a lot of signal loss over 20 feet at 1.5GHz. You might want to refer to a cable loss calculator to find out what you’re dealing with. Or use a long usb cable.

It may just be a lousy Outernet signal and/or atmospherics. Some people seem to receive the signal nicely and others don’t. Try tuning to 1545.110.000 (on the same satellite 98W) in SDR# (USB, 800 bandwidth) and use JAERO to decode the signal. I bet you’ll find that signal comes in really well.

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Currently I am using a desktop with Windows 10. It has a MSI MB AMD FM2+ type CPU and 16 gigs memory. I have another one an ASUS MB AMD FM2+ type CPU with 8 gigs of memory. I have tried both to test this on, plus a HP Notebook Intel Inside. All have Windows 10 installed and each give the same results. I am beginning to think I must be doing something wrong and have little experience at these frequencies. I’m not giving up. Thanks.

Thank you for the info and suggestions that I will certainly try and I will let you know the results. As for the 20 ft of coax, I bought it just for this and is rated for satellite use at 3 GHz 75 ohms quad shielded. I’ll have to look up the loss at 20 ft. Thanks for your help.

I have been looking at 1545.110.000 with JAERO and WOW. Looking very good. Floor at -38 dbfs and SNR at 18 db. I see several of those signals in a row and very strong as you said. In JAERO I went into settings and downloaded Planes and some settings. I havn’t use JAERO before so I guess I’ll find out when I study up on it. Nice find. Thanks.
I guess I’ll have to order a long USB cable and see if it helps Outernet. The Noise floor and SNR look OK but you can tell the signal is not as strong as the ones I just viewed on JAERO. I’ll keep trying and Thanks again.

If you can’t get the signal to decode it may have have switched to 1.545.074.500 (SDR: USB /1200 bandwidth, JAERO: 1200 baud/1800 Hz). It seems to alternate between the two frequencies.

That frequency isn’t being used at the moment so it probably has switched. So far only the 600 baud/900 Hz decoded.

Hello from Santiago, Chile. I’m using the 98W Inmarstat sat and the SNR of the Outernet service using SDR# is clearly lower than others I’ve found:

1539.87 MHz OUTERNET 9-10db
1539.90 Unknown service 13-14db
1545.910 and 1545.92 Pagers 14-15db
1545.060 to 1545.075 AERO 1200 baud , 19-20db
1545.085 and 1545.110 AERO 600 baud, 17db
1546.000 and 1546.015 AERO 10500 baud, 8-9db

Using outernet-in-a-box v2 and Win10, I get steady frame lock with 3-4 db SNR with some variations during the day and I’m receiving the files.

The patch antenna is located indoors and inside a concrete reinforced building (seismic country, remember?) so I think I could get better signal outside, but overall I’m quite happy with the performance of my configuration.

Congratulations to the team and all the people who’s experimenting with this technology!

Andrés CE3SNA

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Thank you for the information. I just wish I was able to set my hardware up inside. Unfortunately I have nothing but trees and they are thick. So, I took it outside and it doesn’t look like it will work on the Outernet but I am able to pick up the stronger signals from Inmarsat, so it isn’t a complete loss. Thanks again and I really appreciate the contact and your arrangement looks really nice. Congratulations!

Does Inmarsat run a pager service?

Do you have clear line of site through your window? I’m assuming that must be the case; I would be shocked if you are receiving our packets through concrete and rebar. As a reference point, the EIRP of our channel is 18 dBW.

Hi Syed.

It appears to be a service called D+/IsatM2M. It is somewhat explained in a user-contributed list at the JAERO software website ( http://jontio.zapto.org/hda1/Dplus-March-2016-David.pdf ). To my HAM operator ear, it sounds like the slow-rate MFSK digital modes we use in HF (JT65 and OLIVIA)

And yes, I forgot to mention to jhans4 that in my case I have an unobstructed view of the satellite, with the antenna mounted on a tripod next to the open window. But if I close the window, I only get “code lock” and not “frame lock” from the signal thru the glass.

That’s interesting. Anyone know why that would be?