LPB is one of the most unpredictable signals on AMC-21, at least for me. Last week, using my six foot prime focus WSI 'bargain' dish, Invacom SNF-31 and adjustable prime focus feedhorn, I had an unusually high LPB SQ peaking into the mid 70% range during the daytime hours here in Big Bear City, CA, but I always expect the LPB SQ to drop to the 30 to 50% range by late afternoon here when my weather and that in Baton Rouge is clear of radar cells. When I tried LPB with my WSI 36 X 39 inch WSI9036 dish with a DMS Spitfire Elite '0.1' dB LNBF I barely got any signal on LPB by mid-afternoon. I got nothing for Montana PBS with that setup. Since I got hooked on watching the British and Scottish programming, unique to Montana PBS, I optimized my dish for Montana PBS but doing so always reduced the LPB SQ range. I sacrificed LPB since it had usable video for my Openbox S9 with any factory firmware when SQs dropped into the single digit range. However, I have a new LPB problem. Since I recently installed the 8-08-11 factory firmware I noticed thin lines of horizontal pixelation for all LPB muxes. Whether this is a causal relationship is unclear. I tried adding custom TPs and sample rates as I did for Montana PBS but that trick did not fix the LPB pixelation problem. To further aggravate the situation, that pixelation is not there each evening and is truly random. Some nights, like last night, it was so bad I had to change to another AMC-21 mux. I assumed the LPB pixelation was due to my 8--08-11 firmware and that is still a possibility but I did not run an experiment to verify this assumption. The fact that AMC-21 is essentially due-south for my location and the fact that prime focus dish ground noise (about a 10% effect) peaks at due south does not help my situation but this effect is probably negligible. The recent LPB pixelation is something I have not seen from my six foot dish with older firmware builds for the almost nine months since I installed my six foot dish---until about two weeks ago and shortly after I installed the 8-08-11 firmware. I find I must switch to a non-LPB mux to temporarily eliminate the pixelation, but it soon returns, as it did last night with SQs ranging from 30 to 50% and far above signal detection threshold. There is the possibility that my receiver's SQ thermometer is incapable of showing sudden SQ drops to zero if they are of short duration, but it easily sees the longer SQ drops to zero for Montana PBS. I got so frustrated that I tried to call Randy Ward, Director of Engineering at LPB today and a guy I spoke with many years ago when LPB first moved to AMC-21. He told at that time that my old Coolsat 4000 Pro receiver would not cut it for their DVB-S2 signal. Unfortunately Randy Ward was out of the office when I called today. I eventually spoke today to Ken, an LPB engineer, but this time, unlike with my recent call to Norm at Montana PBS, I did not get the news I expected. Ken told me their signal was free from any technical issues and that the problem must be on my end. That means anyone with a pixelation problem who runs a large dish for AMC-21 and who uses an Openbox S9 should at least consider trying different firmware builds to see if this fixes the problem. Until I revert to an older firmware build and thoroughly test it, I will not know if Ken was accurate in his statement he made to me today. For now, I assume he was accurate to the best of his ability, but that still does not explain why LPB SQ drops significantly by late afternoon and continues to drop until it plateaus by LPB primetime, regardless of the presence of radar cells here and there. And then there is the issue of the orbital figure-8 pattern of all Clarke Belt satellites impacting receiver SQ. It is times like this when I feel I never left my R & D engineering hardware design position and went into 'retirement.'
: Hope it does not turn into the worthless white crap.)
