I just got my L band antenna and have been aiming my setup CHIP and SDR that was on sale. Best I seem to get is .5 db and sometimes it says “signal detected” i’m in Las Vegas and aiming rougly south and slightly east at about 45 degree tilt. Am I doing this right?
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Use this website:
N2YO tracks Inmarsat 4-F3
Make sure you enter your location. Register and you can keep all sorts of satellite locations.
–Konrad WA4OSH
So for Las Vegas, NV you will get:
AZIMUTH: 152.5 SSE
ELEVATION: +44
The azimuth is relative to true north. Your compass is relative to magnetic north.
The difference between the two measurements is the declination.
Your declination is 11.6 degrees in Las Vegas. Subtract this from the satellites’s true position to get the magnetic compass direction.
Azimuth (true): 152.5°
Azimuth (magn.): 140.9°
–Konrad WA4OSH
If there is not too much interference in your area, you should get sufficient SNR by just laying the antenna flat. Can you send a screenshot of your tuner settings? If you are using SDRx, then I assume you are using a passive antenna, right?
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Syed,
If I lay my antenna flat here in the Seattle area, I get zip, zero, nada for a signal. We’re pretty far out in the fringes here already.
You don’t want to be laying it flat. Not here anyway. The antenna is quite directional. You really want to aim it at the satellite to get the best SNR possible. Point it in the general direction and then make small changes to bring the signal up.
I have two setups. I’m currently using the DreamCatcher running Skylark 4.4 with the passive air gap antenna on the LNA and SAW filter connection. I had to take my stuff inside because it started raining again. I tried aiming through the patio door, but the low-e glass attenuates the signal too much.
That’s very interesting. In Annapolis, MD, at 39 N latitude, I can lay my active antenna flat and receive fine (SNR of 9 vice 12 if pointed properly). Here in George, South Africa, at 30 S, flat works fine too with my active antenna. An aimed active antenna SNR runs about 7 dB and a flat active SNR runs about 4 dB. Ken
This is my RPi SDRx and passive antenna setup, (passive) air gap antenna properly aimed:
This is the same setup with the antenna flat:
–Konrad, WA4OSH
I guess with L band being discontinued this is a moot topic now.
It’s not a moot topic. You are still going to aim your Ku-band antenna.
This online SatPointer is really easy to use. Enter your location, select the satellite (Galaxy 23 at 121 deg), drag the little blue dish icon over your location. The line points towards the satellite. I find it easier to put the mapping program into the satellite view so that you can see everything better. The tool takes care of everything such as the declination – the offset between a true compass heading and the magnetic heading.
@Syed in this post says that there’s not going to be much aiming with DC-3.0 Just aim the antenna in that general direction.
–Konrad, WA4OSH