I received the kit and I try to use it .
the problem is that the SNR is 0.14
what I have to do???
I received the kit and I try to use it .
some details would help
You need to tell us (and the software) which satellite it is supposed to be using, so where are you?
- ensure you have set up the "tuner2 in Skylark to the correct satellite for your area .
- the point that flat part of the antenna roughly towards the satellite (again depends which satellite & where you are) preferably outside
A screen shot of the “tuner” application on Skylark will help you get support too
I am in Israel so I choose Asia and Europe satelilite.
I changed the point that the flat part roughly
Is it possible to put up a screen shot of the Tuner in Skylark?
If you are 100% sure you have the flat front of the antenna pointing close to the satellite (did you use a satellite pointing application on a phone or something?) then the you should have a look at the Rssi number. It kind of represents noise level. The more negative it is the better
I personally found that a local TV satellite receiving dish was wiping out the outernet satellite signal - turn off the tv set top box and it came good.
As @neil said before, you need to point the Antenna at the Sat. Also there are various things that can wipe out the Signal. In my case it was my Desktop PC…
You also have to be outside or at a Window. You need a line of sight to the satellite to get a strong signal.
Here are some pointing numbers for israel. That should get you a signal, but not the best.
Azimuth / Direction: (compass / mag): 194,5°
Unless the Outernet implementation of RSSI is different than industry standard, the higher the RSSI number, in other words, the closer to 0, the better the signal. The more negative it is, i.e. lesser than 0, the fainter the signal. So, -104dB RSSI is a much better signal than -120dB RSSI
try this, looking for AlphaSat in search :
Please forgive me for making a boo-boo…
I bow to your superiority, I was just trying to be helpful… I was under the impression that the RSSI in this case was the relative level of the noise floor, which you want lower.
Obviously I was wrong.
Just didn’t want a noob to keep turning the antenna until the RSSI goes to -145
many thanks. I will try
It looks like you have no signal. Is there a RED light on the preamplifier board? It should be on and the connections should be “finger tight”
According to @k5ted the Rssi number of -83 should mean that you have a huge signal, but I read that as you have a HUGE amount of noise
Where is your antenna? is it outside ( best to start with it out side to get it going.) It needs to have a 100% clear view of the satellite ( no trees or things in the way) and try to keep than antenna and the pre-amp away from electronic “things”.
Basically what seems to be happening is that you are just not getting enough signal from the satellite, there can be a number of reasons for that. in no particular order
- poor placement/connection of the antenna
- too much local noise from computers, sat TV dishes commercial transmitters etc.etc. etc.
- Problem with the Pre-amp not amplifying (usually if the light is on it is working!)
- some problem with the receiver hardware ( I don’t know what sort you have there, but you may be able to plug it directly into your PC and use a program like HDSDR to see if you can see the signal on the spectrum display.)
In all honesty my first test would be to take the whole thing to a park, where I can see the sky well and see if it connect to the sat
The reason I came to that conclusion is because with mine, when I turn on the LNA for the sat TV, which is a good 10 feet away from the patch antenna, ( which is outside on the end of low loss coax) my SNR goes down to 1db from about 4 or 5 and my Rssi goes UP from -116 from -118 and I lose lock then it starts to scan around.
With our friend here, I see his Rssi is a HUGE -83 db and, in my experience I would draw from that that he has a noise floor that is destroying the faint outernet stream. I do understand that these are conclusions made on minimum data but…
I wonder if @Syed or one of the team would be able to clarify for sure… all the (admittedly few) online skylark/librarian systems I have seen have an Rssi of about -115 to -120 db (from memory!
If he has the new SDRx, the LED that should be on is white
@saed I would also try to go to a field or a park where you have not that much noise and a good look at the Sky where the sat is. Was the antenna pointed as i said (or after a sat finder) when you made the picture above?
regards from Germany,
I’ve never seen RSSI below -100.
Oh yes, he has plenty of signal from something that is not the satellite he wants. Possibly the same thing you were experiencing if there’s a satellite LNB nearby. Or, could be USB noise from a faulty cable, a noisy USB bus, bad USB cable shielding, or if it’s POE, a noisy power supply. More than likely though, it is some RF device. Could even be a wireless camera.
I agree with @Syed’s response on Rssi. In my recent travels thru Italy, I found some city locations had high (over -100 dBm) Rssi with 0 SNRs. In some cases, changing locations by 100s of feet made no difference. In other cases, I had to find shielded locations behind iron balcony grills to block spurious signals which dropped my Rssi by over 10 dB, but garnered usable SNRs.
It is quite educational to take a know working Outernet receiver on a trip outside of your local area to see how its performance changes. Naturally, when Outernet gets deployed to “Internet under-served areas”, these issues of spurious signals should not be a problem, but it will be interesting to get some reports about this by fellow Forum Members. Ken
Therefore the less negative the rssi the “noisier” the location, so less chance of getting a usable SNR.
In my original post I said "then you should have a look at the Rssi number. It kind of represents noise level. The more negative it is the better" And I still stick by that statement 100%
But that is not correct!
The RSSI is the signal level, not the noise level. Only when it is very high and there is no lock, you
can conclude that you receive a lot of unwanted signal (interference). When this is not the case, it
is the level of the wanted signal and should be optimized for least negative value.
(however, this really doesn’t matter. it is the SNR that determines the result. I added a 5M coax cable
between the LNA and RTL-SDR and of course the RSSI was lower (more negative), but this had no
influence at all on the SNR)