Excel spreadsheet for concentrating infos of LNBs for EH2 RX

  • There exists already a very complete LNB overview on the internet, including specs and board photographs.

    Look here please: http://www.pabr.org/radio/lnblineup/lnblineup.en.html


    Maybe we can use this file as a basis and expand it /refer to it with a spreadsheet showing links to specific product measurements and modification articles.


    There is very much information available, but it is hidden in forums, twitter and personal sites.


    Especially info about the improvement of stability by remote feeding the LNB with a rock-stable/low phase noise LO signal can be interesting for many OM's.


    73 de PA0P Cor

  • There are missing a lot of LNBs which are in use actually.


    Not one with TFF1017 is in the overview.


    Just talked to a OM with a Goobay 67269 LNB and he sees also a wobbling in the spectrum. PLL used there is the TFF1017


    We need to get a fix to that problem with the TFF107x ICs.


    vy73 DB8TF

  • Several chips have wobble and I have a partial cure that I'll publish in the next few days.


    73's Dave

    Dave Cawley | Ex G8EAO & G6ANG/T |
    (when you had to have a separate TV license !)

  • To add Infos to the spreadsheet click with the right mouse button on the field and select "add commentar".


    I will check the submitted data and put it in the spreadsheet.


    vy73 DB8TF

  • Hello,

    I am using the Goobay 67269 LNB with 25 MHz TCXO and have not noted any wobbling.

    The list should include a pic showing the wobbling of the frequency, before distributing any info regarding wobbling.

    73

    Mike

  • OK Mike, go on and take a picture of the Goobay LNB on the CW Beacon, about 1 min and VBW 1kHz on the waterfall.


    I will change the data in the list if there is no wobbling.


    Also i will (if you agree) include the link to your pic.


    Vy73 DB8TF

  • Hi Flo,

    many thanks for creating the overview.. should be very helpful.

    Maybe you can add here an description or example regarding the "wobbling".

    Is this short term instability with or without TCXO or external reference?

    What is causing it? Vibration or thermal effects?

    TCXO's usually can be very sensitive to vibration, in industry some special damping glue is used....

    73s Peter

    Peter Gülzow | DB2OS | AMSAT-DL member since 1983 | JO42VG

  • Hi Peter,


    the "wobbling" is a constant changing LO freq with +/- 50-400Hz per second in both directions. In german we would say the cw beacon "jault".


    It has nothing to do with the long term frequency drift.


    It is not depending on vibration or temperature changes.


    On the TFF1017 PLLs (GM201)and the HD Line BP2 it can be seen (and of course heard!) if you tune to the CW beacon.


    I take some pictures, so it would be clear what is meant.


    Vy73 DB8TF

  • Here are 2 pictures, one Opticum AX LNB which gives a clear signal and a GM201 which "wobbles".


    Here is the recording of the Opticum:

    https://vocaroo.com/i/s1mvvw5hMvhV


    Here in comparison the GM201:

    https://vocaroo.com/i/s0eSGAUm5gsA


    Both LNB AFs are SW corrected with 1Hz steps.


    The Opticum was already warmed up, the GM201 was currently warming up.


    No wind here, no vibrations on the LNBs.


    Maybe i have unluckily bought 4 GM201 LNBs one HD Line BP2 which are bad ones?


    No wobbling problems with the Octagons and the Opticum.


    vy73 DB8TF