sl3s + 21v pi + frequency sweep from 150mhz to 2150mhz

Discussion in 'DIRECTV General Discussion' started by tdbone1, Jan 21, 2019.

  1. tdbone1

    tdbone1 Member

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    here is my latest info:
    hooked an sdr up to each swm16 port going to the LNB
    SWiM16 and the picture.
    Top to bottom
    18v
    13v
    18v22khz
    13v22khz
    [​IMG]
    looks like two identical pair?

    when performing the test all 4 lnb wires are hooked to swm16.
    i only unhook one at a time and having the splitter goto sdr.
    the other 3 cables i leave plugged in.
    i did that to each port.
    should i try testing with none of the swim16 lnb ports connected except the one under test?
     
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  2. dreadlk

    dreadlk Hall Of Fame

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    The fact that I clearly do not understand what the SWM system is doing kind of makes me hesitant to make a comment.
    I think your getting close and applaud the work you have done but in some ways I wish you had just used a WB68 and gotten away from SWM. My approach when going into things like this is to remove all the variables I have no clue about and then work with the things that I understand. Once I have a good idea of what I am looking at I will then add in the unknowns like SWM and see what it is doing.

    I look at your picture and I see that each of them are slightly different but they are mostly the same. That is not the result I would expect!
     
  3. dreadlk

    dreadlk Hall Of Fame

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    Ok you lost me at "Custom DTV decoder commands". I assume some software is out there for this, but of course none of us have that so we would have to do a lot of legwork to try and figure out the SWM commands.

    This is why I posted to @tbone1 to dump the SWM and just focus on a straight signal that is not rearranged by the SWM.
    Anyway if it is the whole SWM system he is trying to understand I guess he is on the right path, if it's just seeing the TPN's and identifying them this seems like the really long way to get there.
     
    Last edited: Feb 20, 2019
  4. slice1900

    slice1900 Well-Known Member

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    When you are connecting the splitter to the SDR, you have the input of the splitter going to the LNB and one output to the SDR and the other output to the SWM16, right? So long as you are doing that, it doesn't matter whether the other three cables are connected or not it won't affect the output you see with your SDR.
     
  5. P Smith

    P Smith Mr. FixAnything

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    seems to me, looking at the similar spectrums, he didn't connect coax to SWiM, only to SDR :(
     
  6. tdbone1

    tdbone1 Member

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    Jan 21, 2019
    will be getting more splitters, WB68 and probably hr24 in a couple weeks.
    all i have is the stuff i have now to play with.
    i do have a cool idea that im going to do after awhile. will post results after i make a video. have cool idea but it might not make useful results.
    will see after i wake up and have a coffee or two.
    i have two SWM Splitters (SWM18-R3 MSPLIT8-R1) and one "Channel Master 1220IFD" (40MHz to 2050MHz).

    i dont think the Ka LNB is activating.
    i posted something about a 5v mod that perm enables the Ka L/O
    does anyone know anything about this?
     
    Last edited: Feb 20, 2019
  7. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

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    Where's that bucket of cold water?

    The only thing that might come from this is to have the TS learn somethings.

    otherwise this looks to be useless
     
  8. tdbone1

    tdbone1 Member

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    Jan 21, 2019
    the label does not show how they operate does it?
    the info i provided explains how they are on "all" the time. reguardles how many of the 4 lnb cables are plugged in.
    also they do not switch on or off they are on as long as the swm16 is powered on.
    pretty strange since both Ka and Ku L/O are not both on all the time.
    interesting.
    magic in the lnb or magic in the swm16?
    when i order the WB68 i guess i will find out.
     
  9. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

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    I see Captain Obvious has found his sidekick: Captain Clueless


    Ka [output] is above & below Ku output.

    You can't "see" anything until its aligned.
     
  10. P Smith

    P Smith Mr. FixAnything

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    Duh !

    @tdbone1 - did you point correctly/pecisely your dish to 99/101/103 sats ?
    Or it's still hanging in your room ?!
     
  11. HoTat2

    HoTat2 Hall Of Fame

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    Well no, it's actually been a very long known feature of the SWiM-16, or for that matter any powered multiswitch. To provide continuous signaling voltages and tones on their trunk inputs. Thereby essentially having a built-in "polarity locker" for a legacy LNB.

    And AFAIK, the LOs in the LNB are always powered whenever voltages are applied to any or all of it's inputs.

    Sent from my LM-V405 using Tapatalk
     
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  12. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

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    [CO to CC]
    You are correct. the 13/18 volts powers "and selects" polarity.
     
  13. tdbone1

    tdbone1 Member

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    i "think" i have 99, 101 and 103.
    its hard to be 100% for sure without a picture.
    i was thinking about making some kind of markings to tell my exact azimuth.
    maybe im peaking the wrong sat?
     
  14. P Smith

    P Smith Mr. FixAnything

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    @HoTat2, as LNBF has +5VDC VR inside
     
  15. P Smith

    P Smith Mr. FixAnything

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    most likely … get IRD from someone , just for correct aiming
     
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  16. HoTat2

    HoTat2 Hall Of Fame

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    Oh sure, ....

    I'm not saying the LNB's internal cicuitry directly uses the 13/18 vdc control voltages.

    No doubt it's stepped down, filtered, and regulated to a +5 supply as you say.

    But that's still derived from the 13/18v control signal from the powered multiswitch, polarity locker, or receiver.

    Sent from my LM-V405 using Tapatalk
     
  17. dreadlk

    dreadlk Hall Of Fame

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    Man oh man, I just assume you had this hooked up to a working aligned dish system:confused::( I wish you had stated that this was not the case from the start! You cannot do this stuff if you have a bunch of unknown variables floating around.
     
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  18. P Smith

    P Smith Mr. FixAnything

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    He is good learning smart guy - he will grab everything pretty quick, I'm sure.
    We are all been in that position long time ago...
     
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  19. P Smith

    P Smith Mr. FixAnything

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    That was data from old LNBF, now I'm looking at 3D2 [DSWM Gen2] PCB and there is silk print: 3.6V and 3.3V (this rail going into RF PCB);
    for 3D2RB it would be 7 different rails (soon to be measured).

    And while I'm staring at the PCBs, 3D2RB is using Broadcon FSB chip BCM4551IFSBG, when 3D2 - MXL865.
     
    Last edited: Feb 21, 2019
  20. slice1900

    slice1900 Well-Known Member

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    I suspect the chip chosen varies between manufacturer (WNC, Eagle/PBI/Prime, etc.) rather than LNB model. Directv doesn't care what chip is used, so long the LNB meets the spec. So you might find other 3D2RB with different -xx part number using Maxlinear.
     

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