Setting up a Big Dish

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Fine tune elevation.

Once again, lift and pull the dish on the satellites on the low ends of the arc
to see which direction produces a better picture (stronger signal). As stated in
previous step, lifting and lowering the dish has the momentary effect of making elevation changes to the mount - if you are using a spectrum analyzer to tune the dish then you will be able to visibly see if the signals are weaker or stronger as you lift and lower the dish otherwise watch the image on the TV screen and/or the strength meter on the receiver. If lifting the dish on both sides produces a better signal, including the center satellite (or at least does not affect the center) then slightly increase the elevation angle. If lowering the dish on both sides produces a better signal, including the center satellite (or least does not affect the center) then slightly reduce the elevation angle. Keep track how much you turn the bolt(s) that adjust the elevation angle so in case you overadjust you know how much to 'back up' the adjustment. A rule of thumb is to only move the elevation adjustment bolts no more than a quarter of a turn per adjustment. After each adjustment quickly check all satellites to see if they are better or worse. You might have to go from side to side and repeat the elevation adjustment steps before the dish tracks to your satisfaction.



Fine tune declination (end of the arc adjustments).

If, and ONLY if, you can not get both sides to peak, and both sides would be too low or too high while the center remains the same; you can then do a small adjustment of the declination angle to get the two sides into peak with the top. BUT, only do this if you can confirm that both sides are low or high while the center remains the same. If the dish is too high on the sides (arc ends), but fine in the center, the declination angle is too low so increase the declination and decrease the elevation angle the same amount. The two adjustments will cancel each other in the center of the arc while tracking lower on the sides. Conversely, if the dish is too low on the sides (arc ends), but fine in the center, the declination angle is too high so decrease the declination and increase the elevation angle the same amount. One thing to remember, the satellite dish also receives random noise, earth thermal noise, from the earth in addition to signals from space. Random earth noise is something we can not control and is generated by internal molecular motion of all matter; therefore, when the dish is at its peak, it is receiving less thermal noise than when it is positioned looking out on the horizon. Therefore, lower end satellites will always show a weaker signal than higher arc satellites - all things being equal. If your satellites of interest are on the low end of the arc and those satellites are delivering weaker signals to
your system after your best efforts at tuning the dish, then you will require a
larger diameter dish though installing the best rated LNB you can afford might
overcome this. Note, a larger diameter dish will take in more thermal noise, of course, but the increased satellite signals it will gather are more significant than the increased thermal noise it will pick up. The side lobes of a larger dish are smaller in comparison to its main lobe so a larger dish receives less per cent noise per signal as compared to a smaller dish and, as the chart indicates, consequently shows to receive less noise than a smaller dish. so that a larger diameter satellite dish is the clue to overcoming weak signals from low end of the arc satellites.

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Using spectrum analyzer.

You should now have a perfectly peaked dish and you can check this using a
spectrum analyzer. A spectrum analyzer displays frequency vs. amplitude of all carriers, per polarization, per satellite. If you used Ku-band satellites for
peaking, it will be as good as it can be. If you used C-band satellites, you will
want to repeat the fine tuning steps using Ku satellites. As you go from satellite to satellite in the tuning process, note the weakest channels on each satellite and see what effect your adjustment process has on them. If at the end of the adjustment process and there are still weak channels then check the eirp footprints (eirp for Eastern Hemisphere satellites, for Western Hemisphere satellites) for that satellite and channel (transponder) to see if they are aimed into your region and, if possible, use a spectrum analyzer to look at the weak channels (transponders) and see how weak they really are in comparison with the stronger channels on other satellites with similar eirp patterns to see if ground effects are playing a role in reception and/or if your tuning is that much off. Also compare weak channels to strong ones on the same satellite to see if the weak channels might belong to a broadcaster that is simply not uplinking a strong signal or is uplinking a half transponder signal. All these actions will give you peace of mind that you have done the best job possible and will tell you if what you need is a bigger dish to receive the weaker channels. On older satellites it is a fact that some transponders age quicker than others and thereby are inherently weaker. A spectrum analyzer allows more quantative understanding of the variations in transponder reception per satellite than does monitoring each channel with a TV. In regards to final tracking of the dish, in general, it is said that Ku reception is three times more sensitive to tracking errors than is C-band and tracking Ku satellites is really where a spectrum analyzer comes in handy. The last thing to do after satisfying yourself that your installation is its best, apply VNR (video noise reduction) and/or bandpass filters, as built into
your receiver, to any channels which still show a few sparkles. A satellite
receiver with a good set of internal filters (especially Chapparal brands) will
increase video quality by a 'grade', i.e. make a 'B' grade image to an 'A' grade. If you are using a frequency tunable receiver (again, Chaparral), then try adjusting the center frequency and frequency range of any channel that is giving you a problem especially if you think they might be half transponder transmissions or transmissions on non standard transponder bandwidths, i.e. a downlink on a 54MHz transponder.

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SUMMARY:

Find top satellite first then satellite at lowest arc position then program
satellites in the middle between these two then program your way down to the lowest satellite at the other end of the arc. Always adjust north-south axis before making elevation/declination adjustments. Always adjust elevation before making any declination adjustments. To determine whether to make elevation or declination adjustment, program as many satellites as possible into satellite receiver then use this chart to analytically see which adjustment is appropriate.(The best manner to understand this is to understand that the satellite arc makes a half circle and that the tracking movement of mount of dish makes another half circle and when these two half circles are aligned then dish is properly tracked.)If at any time a satellite signal quality can be improved by manually lifting or lowering the dish then your adjustments are not complete. A perfectly tracked C-band arc can appear to be 'all over the place' when you go to program the Ku satellites - do not be shocked. So repeat fine tuning steps on the Ku arc but stay away from further north/south adjustments in Ku fine tuning unless you are really convinced it will be beneficial or you can really get 'mucked up'!! Be sure, on Ku, that you are not chasing weak or half transponder channels and that your dish size relative to site location relative to transmitted footprint is conducive for high quality reception from the questionable weak signal, i.e. check the footprint of that transponder to see if it is being transmitted to your region. Ku signal strength can vary greatly from transponder to transponder within a satellite - especially on hybrid C/Ku satellites. On Ku, national news feeds are
usually strong throughout the coverage region; regional feeds may be on a spot beam; local news feeds may be uplinked weakly and dependent on a very large dish at the home station to bring in a quality picture; private educational classes are often half transponder transmissions and depend on a very large dish at the receive site to bring in a quality picture. For dedicated Ku satellites the energy level of the transponders is more even and your major problems will be one of spot beams - you may be under a strong regional coverage yet be marginal in a spot coverage.If you really want to 'play' with your system further (and your wife does not mind), position and leave the dish on the satellite with weak channels and experiment with moving the focal point (the feed) in and out slightly then with moving the setting of the F/D ratio slightly. Remember that warped dishes (antenna
symmetry), missing panels, hail damaged panels and loose bolts in the mount (especially check the bolt that connects the pivot axis tube to the mount cap) will deter top performance from your system - and Ku reception is the most sensitive to incorrect focal length and F/D settings.When you are satisfied with your efforts, recheck that all bolts are completely tight and definitely tighten the mount cap to axis tube bolt. Also, make a definitive mark on the pole/mount cap for the correct alignment just in case extremely high winds should cause the dish to rotate slightly on the pole. In high winds, position the dish at the top of the arc at which point is the least resistance to wind forces; aiming the dish into the wind will put the most strain on your installation.