Well,
I've just lashed together a first attempt at receiving the downlink from Es'hail-2.
If you have been asleep, the is the first ever Geostationary Amateur Satellite and is a bit fab 'n' groovy!
I'm just using an Amazon sourced LNB:
I've stuck it on a dish I had lying in the hedge and attached it to an Azimuth and Elevation rotatormabob - you may remember that setup from here.
There's an LVB tracker with computer driven elevation and azimuth control.
I pointed the dish in very roughly the right part of the sky and then tuned around where I expected the signals to be, with the narrow band transponder downlink at 10489.550 - 10489.800. I've subtracted the 9750 local oscillator in the LNB.
I then found some signals and used the rotator controller to peak the signals - I've ended up at 149 degrees to the south and 18 degrees elevation - there will be many, many errors in my setup at thus time.
I'm a bit off frequency, and also drifting a touch. I need to add external frequency lock to the LNB. I've also started to setup an uplink based on the system we made here.
But I've certainly found it:
So the low beacon on the narrow band transponder is sending:
5i 5i 5i de qo-100 BK dl50amsat
and I am receiving this at a constantly drifting down frequency, currently at:
739.306 MHz on my SDR. So I add the 9750 MHz Local Oscillator and we get 10489.306 MHz
If should be between 10489.550 and 10489.555 MHz so I am a bit out of bonk and drifting.
Next job - lock the LNB to a frequency reference!
Much more to follow on this topic!
** UPDATE 1 **
I've modified my LNB to take an external 25MHz frequency - so I can feed it with a locked reference.
This has been done in accordance with the instructions here.
I'm feeding the LNB with some cheap co-ax from Amazon and I have replaced one of the "F" connectors with a BNC and attached it to my Leo Bodnar reference which I have set for 25MHz.
According to the instructions (well, read box) from the LNB:
Model: OQSLG Green HQ
Input: 10.70 GHz - 12.75 GHz
LO: 9.75 / 10.6 GHz (10.6 with 22KHz signal on coax)
0.1dB noise ratio
Gain: 60-65dB
Horizontal 18V; Vertical 12V
Now, with the 25MHz external reference, the low end beacon on the Narrow Band segment of the satellite is exactly on frequency:
I'm still worried about LNB skew as switching to horizontal doesn't null out this beacon completely = not even sure if it should, but I am definitely not seeing the DATV beacon yet so more fiddling is required.
** UPDATE 2 **
I've fiddled and now can receive the DATV beacon:
This is really quite fantastic!
I've just lashed together a first attempt at receiving the downlink from Es'hail-2.
If you have been asleep, the is the first ever Geostationary Amateur Satellite and is a bit fab 'n' groovy!
I'm just using an Amazon sourced LNB:
I've stuck it on a dish I had lying in the hedge and attached it to an Azimuth and Elevation rotatormabob - you may remember that setup from here.
There's an LVB tracker with computer driven elevation and azimuth control.
I pointed the dish in very roughly the right part of the sky and then tuned around where I expected the signals to be, with the narrow band transponder downlink at 10489.550 - 10489.800. I've subtracted the 9750 local oscillator in the LNB.
I then found some signals and used the rotator controller to peak the signals - I've ended up at 149 degrees to the south and 18 degrees elevation - there will be many, many errors in my setup at thus time.
I'm a bit off frequency, and also drifting a touch. I need to add external frequency lock to the LNB. I've also started to setup an uplink based on the system we made here.
But I've certainly found it:
So the low beacon on the narrow band transponder is sending:
5i 5i 5i de qo-100 BK dl50amsat
and I am receiving this at a constantly drifting down frequency, currently at:
739.306 MHz on my SDR. So I add the 9750 MHz Local Oscillator and we get 10489.306 MHz
If should be between 10489.550 and 10489.555 MHz so I am a bit out of bonk and drifting.
Next job - lock the LNB to a frequency reference!
Much more to follow on this topic!
** UPDATE 1 **
I've modified my LNB to take an external 25MHz frequency - so I can feed it with a locked reference.
This has been done in accordance with the instructions here.
I'm feeding the LNB with some cheap co-ax from Amazon and I have replaced one of the "F" connectors with a BNC and attached it to my Leo Bodnar reference which I have set for 25MHz.
According to the instructions (well, read box) from the LNB:
Model: OQSLG Green HQ
Input: 10.70 GHz - 12.75 GHz
LO: 9.75 / 10.6 GHz (10.6 with 22KHz signal on coax)
0.1dB noise ratio
Gain: 60-65dB
Horizontal 18V; Vertical 12V
Now, with the 25MHz external reference, the low end beacon on the Narrow Band segment of the satellite is exactly on frequency:
I'm still worried about LNB skew as switching to horizontal doesn't null out this beacon completely = not even sure if it should, but I am definitely not seeing the DATV beacon yet so more fiddling is required.
** UPDATE 2 **
I've fiddled and now can receive the DATV beacon:
This is really quite fantastic!
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