Select your language

Commissioning of the Laminas 2700 dish - the second day


The next morning I turned on the satellite receiver again and the Astra 19.2 ° E signal was still there. 10.5 dB on such a large dish is desperately low, but it was there. This meant that the direction on the satellite was correct and that even with the offset dish turned horizontally, the satellite could be aimed and thus receive its transmission.

I compared my assumed calculated positioner orientation values with the actual ones. And a surprise awaited me. The error in the azimuth position was quite small, only 590 pulses, which is less than 3°. In contrast, the elevation error was 3835 pulses, which is almost 5°. The unsuccessful search for the signal the day before was caused by the mistaken assumption that the elevation was approximately correct and therefore we did not increase it sufficiently. Then changes in the azimuth to the greatest extent could not bring any usable result.

Attempts to achieve greater signal strength followed. First, I manually turned the LNB to find the optimal setting for the skew converter. The signal strength increased to 15.2 dB. By further specifying the azimuth and elevation, the signal strength could be tightened to 16dB without any problems. The signal was kept at full level by moving the parabola ± 0.25° in the azimuth direction and ± 0.15° in the elevation direction. At that moment, it was clear that I had won.

The signal from the Astra 19.2° E and with a dish with a diameter of 270 cm was really strong. My worries that such a strong signal will already have a problem processing the LNB, but they were unnecessary. Apart from the permanent 16 dB signal strength indicator on the screen, it was not known that the signal was extremely strong.

The next step was to try to find the position of another satellite. Since I already knew the correct value of the azimuth and elevation of the Astra 19.2° E in the pulses of the EGIS positioner, I recalculated these values for the position 28.2° E. I turned the parabola as calculated and the signal jumped. It was necessary to further specify the azimuth and elevation, but I already knew that other satellites could be found by mere calculation. The long search for a blind signal was the final end.

I started searching for programs in the receiver and channel names that I had not seen before started to appear. Evidently, it was possible to accept even a weak British bond. That made me very happy. Even if I didn't catch anything else, this broadcast was worth the effort. It was reaching the goal I had been dreaming of for a long time.

Then a friend came to visit again and my enthusiasm cooled down quickly. He asked how strong the signal was for Freesport HD. And lo and behold, this program was not at all in sight. Then he asked about BT Sports, a package of American programs. None of this was tuned. Disappointed, I began to systematically search frequency after frequency and found that I had zero signal for 7 packets. That was a great sobering up. Somehow, in the corner of my soul, I foolishly believed that with a dish with a diameter of almost 3 meters, everything had to work.

This was followed by testing of all three available LNBs. Because I also adjusted the orientation of the dish after each LNB change, it soon became clear that the maximum signal for different packets is in different directions. The best results were given by LNB Invacom. With his help, two more packets were put into operation. It improved my mood a bit. As a compromise, I aimed the dish at the position of the weakest packet. With this setting, it was possible to watch the programs of other packages. The signal strength ranged from 6 dB to 11.5 dB. However, there were still 5 frequencies with a permanently zero signal.

Another attempt was to find a position of 36.0° E. I was interested in how strong the signal will be for Russian programs and whether the converter with linear polarization can receive packets with circular polarization without any modifications. Finding a satellite by calculation was no problem. After tuning the receiver, several programs broadcast by circular polarization did appear in the list. However, these were only rare exceptions. For serious reception of Tricolor or NTV transmissions, it would be necessary to either supplement the LNB with circular polarization or to supplement the existing LNB with a polarization plate. I will definitely return to these attempts in the future.

Another tuned position was 26.0° E. It has been shown here that broadcasts to Europe can be received without any problems, but volumes destined outside Europe show no signal. At this point, I was slowly beginning to understand that even a three-meter dish is not a panacea. You will still have a long way to go to receive really weak signals.

Since it was already around eight o'clock in the evening, I decided to stop experimenting and returned the dish to the 28.2° E position. And I was amazed to find that all the income from the British bond was gone. I checked the correct orientation of the dish, but that was fine. The signal only occasionally had a few elusive decibels, but was mostly at zero. Little did I know that this was a common phenomenon, when the signals of the British bond towards the evening would noticeably weaken. In addition, it was sunny again that day with temperatures around 30° C. And such signal conditions from 28.2° E probably do not indicate. And so my second day ended with a big dish of embarrassing disappointment.

No comments

Leave your comment

In reply to Some User