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<blockquote data-quote="Waveguide" data-source="post: 878448" data-attributes="member: 364636">The short story: Invacom SNF-031 is better than Inverto Black Ultra with C120 flange!&nbsp;The long story:Saturday evening the &quot;Evening Sickness&quot; (daily signal variation) gavea total signal loss on BBC News HD between 21 to 23 CET. BBC 1 HD hadno problems. (10847V tp50 &amp; 11023H tp61 were used in all tests) This was with the Inverto LNB and on sunday it was replaced with theInvacom LNB and signal strength was measured between 16 to 24 CET.The threshold was 7,0 to 7,1 dB SNR with the Inverto and the Invacomnever went below 7,6 dB so there were no dropouts at all with Invacom.The total daily variation was around 1,5 dB.&nbsp;The Inverto has a larger difference in SNR between H and V polarisationand I suspect the cross polarisation isolation is the real culprit.It is lower in the specs for Inverto, 22 dB compared to &gt;= 25 dB.The E-field probes inside the LNB's (signal pickups for H &amp; V) look much &quot;nicer&quot; engineeringwise in the Invacom. The Inverto looks lessaccurate with the probes beeing slightly off from perpendicular.Mistake on the production line or shoddy tweaking procedure?Anyway, adjusting one polarisation makes the other less than optimal.&nbsp;Only the LNB's were swapped, the dish was fine-tuned before the testand never moved during the test. The polarisation angle was the onlything adjusted individually for each LNB.Me Mythbuster - Inverto Black Ultra is not for prime focus dishes!</blockquote>

[QUOTE="Waveguide, post: 878448, member: 364636"] The short story: Invacom SNF-031 is better than Inverto Black Ultra with C120 flange! The long story: Saturday evening the "Evening Sickness" (daily signal variation) gave a total signal loss on BBC News HD between 21 to 23 CET. BBC 1 HD had no problems. (10847V tp50 & 11023H tp61 were used in all tests) This was with the Inverto LNB and on sunday it was replaced with the Invacom LNB and signal strength was measured between 16 to 24 CET. The threshold was 7,0 to 7,1 dB SNR with the Inverto and the Invacom never went below 7,6 dB so there were no dropouts at all with Invacom. The total daily variation was around 1,5 dB. The Inverto has a larger difference in SNR between H and V polarisation and I suspect the cross polarisation isolation is the real culprit. It is lower in the specs for Inverto, 22 dB compared to >= 25 dB. The E-field probes inside the LNB's (signal pickups for H & V) look much "nicer" engineeringwise in the Invacom. The Inverto looks less accurate with the probes beeing slightly off from perpendicular. Mistake on the production line or shoddy tweaking procedure? Anyway, adjusting one polarisation makes the other less than optimal. Only the LNB's were swapped, the dish was fine-tuned before the test and never moved during the test. The polarisation angle was the only thing adjusted individually for each LNB. Me Mythbuster - Inverto Black Ultra is not for prime focus dishes! [/QUOTE]

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