CSpan analog clear

Discussion in 'FTA / Non Small Dish Satellite Area' started by AntAltMike, Feb 22, 2019.

  1. AntAltMike

    AntAltMike Hall Of Fame

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    Is it still up and running in NTSC analog on AMC11 131 degrees, 3840 V tp 7?

    I am trying to repoint a CSpan 3 dish that I guess had been pointed at AMC 10, 139 degrees and have to move it to G14 at 125 degrees, but am lost, and trying to get my bearings using my Blonder-Tongue BTSA-5 which can demodulate an NTSC signal. This customer had moved the dish while trying to retarget it themselves, and while they think it is close to where it was, I can't use that approximation as a relaible starting point.

    I have swept the lower, western arc twice but not yet seen the analog channel
     
  2. KyL416

    KyL416 Hall Of Fame

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    If they had it pointed at AMC 10 when it was in use for channels it would have been pointed at 135. The last remaining AMC 10 channels including C-SPAN left the satellite back in December and it's currently in the process of moving from 135 to 139.

    Last I heard back in September the C-SPAN analog feed is still live on AMC 11 and they haven't set a sunset date for it yet, but they are suggesting affiliates convert to the digital feeds on Galaxy 14.
     
    Last edited: Feb 22, 2019
  3. AntAltMike

    AntAltMike Hall Of Fame

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    As I move the dish through the arc, I can get the receiver's OSD (on screen display) screen to say it is at the correct intermediate frequency of 1210MHz, which is 3,940 MHz, and on one satellite it locks and says horizontal, with a signal strength of over 70, but I just visited Lyngsat, and I did not find any satellite in that end of the arc that has that frequency transponder horizontally polarized. The receiver's front panel display indicates that it is "tuned" to vertical polarity, but I don't know what that means insofar as the operation of a digital tuner is concerned. With analog, the polarity a receiver is tuned to determines what signal the receiver sends to the switching circuitry of the LNB, but it simply processes whatever comes down the coax. Perhaps this receiver "read'",from the data it decoded, that that one 3,940 transponder that it locked onto had imprinted into its identifier that it is horizontal.

    I already tried spinning the LNB 90 degrees and sweeping the arc, but doing that, I got no signal locals on any 3940-1210MHz IF transponders.
     
    Last edited: Feb 23, 2019
  4. KyL416

    KyL416 Hall Of Fame

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    Any chance they messed something else up like the elevation when they attempted to move the dish on their own, or even worse broke/fry something if they didn't do it right?
     
  5. AntAltMike

    AntAltMike Hall Of Fame

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    Nope. These people are technically solid and reliable. Defense contractor engineers.

    The calculated elevation is about 23.5 degrees. I think that solid offset-feed dishes commonly have offset reflection angles in the range of 21 to 22 degrees measured from their axis, and so I don't need an inclinometer to see that the reflector perimeter is tilted back just a couple of degrees, so it has to be a bulls-eye.

    I tilted the dish way back, raising it to the point where it had to be targeting the Mexican satellites, and spun the elevation bolt, to hold it there and then methodically back-turned that nut a turn and a half at a time and repeaked, using my spectrum analyzer, but the only receiver lock I got was the one with the reflector clearly at the correct elevation angle. The OSD kept saying "horizontal" while the panel display, which is operator selectable, said "V-RH (I think). I'm pretty sure that just means that the receiver is sending out signals to call for either of those LNB polarities.

    I spun the LNB 90 degrees, and stepped through the local arc range again but didn't get a single lock. I then turned the LNB back to its original skew (minus just a few degrees to compensate for the fact that it had been peaked at 135 degrees but now is aimed at 125 degrees) and left it peaked on what I am sure is the right bird.

    I guess I'll call CSpan Monday and see if they have any suggestions. Meanwhile, I would like someone to visually confirm that CSpan is still broadcast in NTSC Clear on satellite T11, transponder 7, 3,840V, because I was not able to view it on my Blonder Tongue spectrum analyzer that has a demodulator built into it.
     
  6. P Smith

    P Smith Mr. FixAnything

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    I would connect my SSA to the LNA cable and watch online signals while moving the dish, then after peaking turn the receiver and play with its settings. I have old Pansat analog IRD for the rare occasions, but not sure if you could use it over there.
     
  7. AntAltMike

    AntAltMike Hall Of Fame

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    Was that Pansat receiver the model that didn't have any panel buttons at all? Or maybe just Power and Channel Up/Down. There was another defense contractor that used to call me out to peak their Radio Shack 9', horizon-to-horizon drive dish about once a year when they were using it to... I don't actually know what they were doing with it, beyond targeting an Intelsat Atlantic arc bird that had no video. I sometimes used that functionally limited receiver for that, back before I bought my Blonder-Tongue BTSA-5, and then we'd use their laboratory grade spec analyzer, which did not demodulate, to guide us from there. Everything at that job site was a secret. I could talk to those guys about anything but satellite.

    There was one nearby Intelsat bird that I would first find that ran the same cartoon show at 3:00 PM, year after year, that I would use as my reference point, from which to nudge over to the correct one. The featured character had a big, block jaw and looked like a lumberjack, but I was never able to demodulate the audio. Anyway...

    You can't do a more thorough and systematic job of analyzing the friendly skies than I did, so I calculate (well, estimate, or should I say, speculate) the chances of the dish not now being pointed correctly are about zero. The temperature was in the mid 40s and windy, so I wasn't up for setting up their receiver and test monitor outside to enable me to more expediently repurpose myself from being dish pointer to system operator and back, and frankly, I was out of ideas by the time I left, so it looks like I'll be handing this one off unless someone can, 1) confirm that the NTSC clear CSpan is still up, and 2) come up with an idea of what other settings can be user selected that I might have overlooked.
     
    Last edited: Feb 23, 2019
  8. P Smith

    P Smith Mr. FixAnything

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    I recall it was KR-600... if my memory is good
     

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