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

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

  1. Jan 21, 2019 #1 of 260
    tdbone1

    tdbone1 Member

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    Jan 21, 2019
    what frequencies are going to the ird from the lnbf (sl3s)?
    i have a spectrum analyzer and im trying to figure out what i should be seeing when i do a sweep from 150mhz to 2150mhz?
    should i see Ka and Ku at the same time or do i need a receiver that can switch to 13v/18v and also a 22khz/0khz for polarity?

    what should i see as far a sats/transponders/bands when i do a freq sweep from 150mhz to 2150mhz? i do think i see 9 transponders from 870mhz to 1870mhz but i not sure.

    here is some more info i found but not sure if it applies to my specific sl3s lnbf

    L-band: approximately 950 - 2000 MHz
    C-band: 4000 - 6000 MHz
    Ku-band: 10,700 - 14,000 MHz
    Ka-band: 18,000 - 20,000 MHz

    LNB between 10.7-11.7 GHz can be easily seen in 950-1950
    not sure if this is correct though so any info would be nice to have
    thanks

    ps
    local oscillator frequencies would be a GREAT help.
     
    Last edited: Jan 21, 2019
  2. Jan 21, 2019 #2 of 260
    P Smith

    P Smith Mr. FixAnything

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    you must go back in time here, when we did discuss SWiM [FTM] invention. I did post pictures from my spectrum analyzer [PSA-37D] that time.
    Later on we got DLNB Gen1 and Gen2 with internal switch, what dramatically changed signals in a coax cable to IRD.
    Also pay attention to frequency band plan discussions, including a role of SUP-2400 converter for Ka signals, if you want to dig into IF signals from analog LNBF.

    BTW, when you're asking such things, a model of your dish is not enough to continue the talk - you must provide LNBF model and (if there is any) SWiM switch, also do disclose a point of tapping by your SA.
     
  3. Jan 21, 2019 #3 of 260
    tdbone1

    tdbone1 Member

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    ive seen info on the sup2400. i figure i would investigate what i already own.
    i thought i did provide the lnbf info. it is an sl3s and the dish is a Directv Slim line
    i can share my spectrum when i do a sweep from 150mhz to 3800mhz
    here is my parts list.
    Directv SlimLine dish
    LNBF = sl3s4nr4-01
    21v power inserter
    20db attenuator
    Limesdr-mini
    i7 laptop
    ubuntu 18.04.1 amd64 desktop
     
  4. Jan 21, 2019 #4 of 260
    P Smith

    P Smith Mr. FixAnything

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    please take your time to pull all the info posted here;
    - frequencies
    - LOFs
    - IF freqs plan
    - SWiM freqs list
    - spectrograms
    - etc

    unfortunately you or someone must spend the time...
     
  5. Jan 21, 2019 #5 of 260
    tdbone1

    tdbone1 Member

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    Jan 21, 2019
    150to3800.png
    sweep from 150mhz to 3800mhz

    just looking for local oscillator frequencies for Ka/Ku and what i should be seeing when im pointed at 101w. not sure if the Ka is working as i pulled the cover off the lnb and i can see the 3 slots where the antennas are.
    when i cover the slots on the sides (Ka) it does not change the spectrum so i believe they are not activated.
    Imgur
     
    Last edited: Jan 21, 2019
  6. Jan 21, 2019 #6 of 260
    P Smith

    P Smith Mr. FixAnything

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    $159 LimeSDR is that what you're using as SA ?

    The spectrogram does show 8 SWiM channels (plus one for network tuner?), but not IF !

    And again (sorry for my persistent) - you must dig the site.

    FYI, I did posted a table of freqs what SWiM technology does using.
     
  7. Jan 21, 2019 #7 of 260
    tdbone1

    tdbone1 Member

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    yea i see the 8 channels or is that transponders plus one network tuner?
    no "IF"? hmmm that is also what i was wondering.
    do i have to have an ird device to control the power 13v/18v or the 22khz/0khz tone to activate/deactivate Ka or Ku and the polarities?
    i have been looking "searching this site" but so far i havent found anything.
    that is why i started this thread.
    its like the local oscillators are top secret ;)
     
  8. Jan 21, 2019 #8 of 260
    P Smith

    P Smith Mr. FixAnything

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    no, not a secret … just, it's sort of your moves in Smithsonian museum while you're there … asking each one there by shouting ;)

    try use Search... modify your keywords... sometime reduce its count to two or one words… don't hesitate to read 100s posts if that simple search criteria bring too much...
    A tip: if I mentioned "I posted.." try to include in your search the author/poster name/nick … etc

    get into old threads where you can soak into SWiM technology... drop the typical the V/H Hi-Lo control for start, new protocol is not about it
     
    Last edited: Jan 21, 2019
  9. Jan 21, 2019 #9 of 260
    P Smith

    P Smith Mr. FixAnything

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    another tip for search: the keyword is LOF
     
  10. Jan 21, 2019 #10 of 260
    P Smith

    P Smith Mr. FixAnything

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    you must find big secret black book of DTV FW coders :) - all FTM cmds are there to control and two-way communication with SWiM devices
     
  11. Jan 21, 2019 #11 of 260
    tdbone1

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    AU9 Ka LNB Local Oscillator
    is that what you guys are talking about?
    im talking about what are the default modes of the LNBF (sl3s) when there is "No" IRD/Receiver.
    i can not tell what frequencies for sure that i am seeing in the spectrum from 150mhz to 2050mhz
    with no ird and only the 21v PI and connected to my limesdr-mini what mode is the lnb in and frequencies in the spectrum?
    mode = Ka/Ku and polarities
    im still searching this site but dont forget. before i came here i was using google too and i been searching this site also but the info im looking for isnt your average everday info.

    here is another SS of the spectrum with no attenuators
    Screenshot from 2019-01-21 10-10-24.png
     
  12. Jan 21, 2019 #12 of 260
    P Smith

    P Smith Mr. FixAnything

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    Yes ! You got first clue in your long quest :D

    Now you'll need to understand SWiM technology. It's in charge if the LNBF does not connected/controlled by IRD. Imagine, it has own uC and small embedded OS …

    Perhaps you're will be a first person who will reveal dirty secrets of DTV in SWiM technology … say, you'll found DEFAULT map of 3 sats Ku/Ka tpns into [8] SWiM channels after booting LNBF's OS !!!

    A tip: first SWM channel is network tpn from 101W. Try to define it's number ;)
     
    Last edited: Jan 21, 2019
  13. Jan 21, 2019 #13 of 260
    HoTat2

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    Although looking at that spectrum display. I'm wondering P. Smith, that given the OP's setup.

    If you remember from the old days of aligning a SWiM type Ka/Ku LNBF. If the LNBF was powered up with 18v or higher, but detected no receiver/IRD connected. It would enter a special "alignment mode"

    Where it would generate two bands of frequencies. A lower one between 950-1310 MHz for 119W. And a higher between 1455-1850 MHz for 101W.

    Then in the era before the AIM meter when techs. used the "Birdog," "Accutrac," "Super Buddy," etc. meters. They had to connect them to the LNBF through a special device called an "ASL-1" which separated those two bands on two output ports for manual individual measurements.

    Just a thought ...[​IMG]

    Sent from my LM-V405 using Tapatalk
     
  14. Jan 21, 2019 #14 of 260
    P Smith

    P Smith Mr. FixAnything

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    Honestly, I forgot it. Actually missed the description, perhaps it was on Installer forum when I didn't pay attention to it ...
     
  15. Jan 21, 2019 #15 of 260
    P Smith

    P Smith Mr. FixAnything

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    anyway, we see 8/9 SWM channels on the graphs and what 101WL sat/tpn on each of 8 is assigned ?
    I would imagine if odd 101W tpns… as they do carry most of APG data... but it should be 101WR
     
  16. Jan 21, 2019 #16 of 260
    HoTat2

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    But it appears that in the second image the OP has tightened the scale on the larger "haystack" (as they call them). Is the narrower haystack still on a lower band of frequencies to the left of the display as shown in the first image?

    So if these are actually SWiM channel carriers, then what is that lower frequency haystack coming from?

    In alignment mode the SWiM multiswitch and it's associated agc circuits are supposed to be disabled or bypassed. And tps. from 101 and 119W are simply down-converted to two bands of frequencies for the ASL-1 to separate to individual output ports for one-at-a-time measurements.

    Sent from my LM-V405 using Tapatalk
     
  17. Jan 21, 2019 #17 of 260
    P Smith

    P Smith Mr. FixAnything

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    could be byproduct of RF transforming... doesn't looks like a set of tpns in SWM stack
     
  18. Jan 21, 2019 #18 of 260
    P Smith

    P Smith Mr. FixAnything

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    doesn't look that way seen the spectrums above … 16 tpns must be seen without such deep on the graphs
     
  19. Jan 22, 2019 #19 of 260
    tdbone1

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    That is interesting info. Never knew about a "test mode".
    What happens if i supply less than 18v power (which i do have a 12v and 15v) would that put it in a different test mode?

    That asl-1 is interesting.
    I read sonewhere that the ka-low was on 250mhz-750mhz and ka-hi was on 1650mhz to 2150mhz and ku is on 950mhz to 1450mhz?
    Idk. Pretty confused as to what im seeing.
    Any info i can provide just let me know.
    Thanks for all the info above
    Just wanted to add that im in iowa. 52655
    also on the limesdr-mini it can Tx a 22.khz wave file at 2mhz control channel?
    it would probably be better to just buy a ird / receiver?
    can anyone recommend a cheap one for use with what i need to do? dont some come with an extra coax output that i could hook that to my limesdr-mini?

    i added this video

    1 more cool one with an app called fosphor
     
    Last edited: Jan 23, 2019
  20. Jan 22, 2019 #20 of 260
    tdbone1

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    here is the 150mhz to 800mhz
    150to800mhz.png
    and with no gain on my limesdr-mini and no attenuators. basically. lnb > 21v PI > limesdr-mini connected to laptop usb 3.0 port (no cord)
    Screenshot from 2019-01-22 23-00-39.png
     
    Last edited: Jan 23, 2019

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