On re-thinking, I think my comment about the
birdog using the channel lineup WAS "horse feathers", not that it wouldn't be the best way, but that I don't think the Birdog is capable of that. But I still find it hard to beleive that it uses the beacons either, mainly because the lnbfs aren't stable enough for it to get an accurate frequency, plus it would almost need to have 2 tuners, one for the narrow beacon, and one for the wide transponders.
My original *ASSUMPTION* about how these meters worked was by having a database of the actual TV transponders on the satellite, and this assumption was reinforced whenever I'd read that people were having problems telling the 2 Nimiqs apart, because while most satellites have what could be considered as an identifiable spectrum of signals, the Nimiq sats have had very similar lineups of transponders, and have for years. For example, if you look in Lyngsat at the first handfull of transponders, on Nimiq1 I see:
12224R,12239L,12253R,12268L,12282R,12297L,12311R,1 2326L,12341R,12355L,12370R
While Nimiq2 has
12224R,12239L,12253R,12268L,12282R,12297L,12311R,1 2341R,12355L,12370R
Ie very similar, but there is one transponder missing on Nimiq2 that could be used to distinguish the two.
Then I looked at the Nimiq2 lineup about a year ago, ie:
12224R,12239L,12253R,12268L,12282R,12311R,12341R,1 2370R
Again similar, but differences from just a year ago.
Then compare to Nimiq2, 2 years ago:
12224R,12239L,12253R,12268L,12282R,12297L,12341R,1 2355L
Again, more differences.
Anyway, my *theory* is that these meters must have several transponders that they look for to identify the satellites, and the fact that the 2 Nimiq sats are so similar with respect to which transponders they use, makes it hard to distinguish between the two, particularly since some of the transponders seem to come and go over the years.
Since your Birdog has worked well for years on Nimiq, I'm guessing that your unit must use a group of transponders that have remained fairly constant over the years.
Anyway, that's my *THEORY*, not based on anything but a guess.
I'm still very interested in whether what you said is in fact correct, and they somehow use those beacons. I have alway been interested in those beacons. They aren't easy to monitor. I "T" off the lnb coax and receive them with my Icom-R7000 (and/or Yaesu 5000), which has multiple modes and bandwidths. I'm not 100% positive that the signals I found were in fact the beacons, because the frequencies were a bit off from the published frequencies, however I blamed that on the drift of my LNB. They were definately within the drift specs of my LNB, and were found just above the bottom edge and below the upper edge of the sat band, where they are supposed to be.
I was hoping to find some kind of identifying modulation, like Morse code or something, that could be used to identify the satellite, but all the signals seemed to be was a plain carrier with no modulation that I could hear. I think it would be really neat if I could find some kind of identifying data in these beacons, but it just didn't seem to be there.
Linear Mode
