30.9°E Türksat 5A

I think that all I am seeing is transponder noise but they could be real signals, I suppose. During testing, the DVB was receivable at 9-13dB SNR. The LNB is an SMW 12.25-12.75GHz PLL which had an 11.3GHz LO in 2021 but I have modified it to an 11.75GHz LO. The performance is only slightly improved with ~2dB NF, still not great. The notch in the 2021 plot is due to the LO spurious in band. I have about 0.15dB ground noise. The dish is a Prodelin 3122 1.2m offset.

Today's scan was the same as the one above with just transponder noise and the beacon. Here is a close in plot of the beacon on 13401V with an SNR of ~35dB in 500Hz:

I could only check horizontal polarisation but there were 3 signals today including the beacon. I used an SMW Q-PLL type R set to 11.3GHz LO. It's not great with a NF of 3-4dB at 13.6G. 1.8m dish.

Beacon on 13401H

Carrier on 13584H

Frequency hopper. 13416H = 421.4MHz, spectrum inverted. Approx 1 hop/second

Zitat von s-band

I could only check horizontal polarisation but there were 3 signals today including the beacon. I used an SMW Q-PLL type R set to 11.3GHz LO. It's not great with a NF of 3-4dB at 13.6G. 1.8m dish.

Iv'e got the three up here again as well , usual beacon @ .401 , for me today the frequency hopping is between 13.415 V to 13.417 V. The strong marker at 13584.5 seems to be circular, possibly LHC. [ only using a linear feed onto a Chinese Universal Ext Ku lnbf on a 1.2m CM dish ]

The confusion over the polarity of 13584 is caused by there being 2 carriers spaced by 900Hz. The lower one is vertical and the upper is horizontal. If you use a wide bandwidth, you'll see a small dip as the skew is swept through 45 deg offset. In an audio BW the 900Hz tone should be audible.

For the plots below I used a modified SMW 12.25-12.75GHz LNB with an LO of 11.75GHz (the system is locked to a Rb source). The NF is about 2dB and the dish a 1.8m PF. The actual frequencies are on the plots.

Congratulations!

It looks like you have registered a transponder with a center frequency of 13583765 kHz in a frequency band of 3.75 MHz, which corresponds to a symbol rate of 3131 kS/sec

My attempt to receive this transponder on the 3rd harmonic of the heterodyne with a 1.05 m antenna and an Inverto Black Ultra LNB was not so successful...

Here is what I managed to "catch" in manual mode:

1.8PF 2dB NF LNB

I don't remember seeing the approx 800kHz wide signals at 13625.5, 13627.5 and 13605.5H which are all much too low to get a lock. The peak at 13526H is from 42E and the signals at the low end of the band were described here. As before, the transponder noise can be seen.

strannik I wonder if you are getting a false positive from the pair of closely spaced carriers on 13584 H & V. If the polarisation is not set exactly, both are present at the same time.