LNB: Current Usable Ones with PLL for NB Transponder

  • Partly success on the HD Line Black Premium LNB. Inspired by OH2AUE's work.


    Remove carefully the crystal and insert a simple bandpass as seen in the pictures.


    Check if you have damaged the connection from the crystal pad to the via, if it is broken use a small wire to fix it.


    Now the LNB could be used on both outputs with the external ref injected to the one you had choosen for connecting the bandpass.


    The ext ref i use is the cheap toyocom TCXO from eBay which i have indoors and temperature isolated so it is relative stable (+/- 100Hz/h). The signal is fed with the known triplexer into the coaxial cable to the LNB.


    With the 26MHz ref from the TCXO now the WB is shifted to the normal receiving range from a normal Sat receiver. (abt 1,106GHz)


    It seems that the LNB gain has dropped abt 3dB, not a problem on my big dish, but on smaller dishes it would be not good. Maybe some additional resistors could improve the gain.


    Vy73 DB8TF

  • I purchased the Telesystem TS100F , use it without any modification but allow it for warm-up 30minutes. It also uses the 25MHz XO and PLL and simple filtering, about 65dB conversion gain.

    In picture: right PBC is TS100F, left PCB is Goobay LNB also 25MHz XO and PLL.


    Being up north, also used a skiing-glove and plastic bag to make LNB less prone to temp.changes - almost no attenuation with glove and bag.


    http://www.telesystem-world.co…lnb-single-universal.html


    I did try to add capton tape on the filters, hoping for IF gain to increase below 700MHz, Not sure if it worked yet.

  • Now i modified the HD Line Black Premium LNB a little bit more and now it is good working.


    I cut the pcb track which attenuates the 26MHz from the TCXO to much and added 2 coils with together ca. 15uH.


    Now the LNB locks with lower ref signal and its gain is only abt 2dB weaker that that from an standard Octagon.


    vy73 DB8TF

  • To bring this to a end: the HD LIne Black Premium stops working when the temperature goes down again. Forget that LNB...


    But if you want a cheap and stable solution MUCH more cheaper than GPSDO and you only want to work on NB with ssb then:


    Buy a cheap pollin GM201, do the OH2AUE mod and feed it with a triplexer from a cheap toyocom TCXO which is INDOORS.


    Works very good and costs below 10€!.


    I know that we have here OMS that say "buy a GPSDO or mod with a TCXO" but for me that is not the final solution. Surely that works but where is the fun on experimental ham radio with those already known solutions???


    My station works perfect (weeks before the lauch of EH2) but i am still interested to find more and other ways to be QRV. Especially on the RX path.


    BTW if i don't wanted to watch the WB on a normal sat receiver i never got away from the SW drift correction which worked from the first day on PERFECT !


    vy73 DB8TF

  • ... i never got away from the SW drift correction which worked from the first day on PERFECT ! ...

    Me too ;-)


    If you use a SDR program as RX anyway (most users do this) and have a non wobbling LNB, that is the simplest solution. Because no LNB modification is required.


    And if there are more SDR programs with integrated software drift correction in the future i think hardly no one will talk about LNB modification, TCXO, OCXO, GPSDO etc. anymore, hi. Except maybe for special applications. This makes it a lot easier for newcomers.


    If the frequency stability of an unmodified PLL LNB is ok for WB reception, simply connect a MiniTiouner etc. directly to the LNB. Without modifications, downconverter etc. I love simple solutions ;-)


    LNB: Non wobbling PLL-LNB (without modifications)

    NB-RX: SDR program with software drift correction

    WB-RX: MiniTiouner (directly connected to LNB)

  • Also tested the Opticum AX Black Buster Twin today and as DG0OPK already wrote this LNB shows now signs of any wobbling. Drift is normal for a unmodified LNB.


    So far the closest solution to replace the old Octagon


    vy73

  • Hi All

    I agree on the statement of DL3DCW that a software solution is an easier way and cheaper too. Simon Brown "SDR Radio Console v3" will update his software soon with this Software feature :-)


    But my final solution should be one dish for the up- and down-Link and one transceiver with fullduplex SAT mode (Up on 2m and Down on 70cm).


    I just tested this morning the Up-Link of my new BaMaTech Dualfeed from dj7gp which works perfect as my current 13cm Helix Antenna with 5 turns. So I'm waiting to get the new Downlink Converter from KUHNE.


    More infos under http://www.hb9ryz.ch/sat


    73 de HB9RYZ

    Wolfgang

  • I also tested this morning the GOOBAY Single LNB 67269, which works fine.


    USB-Cable Extension over a LAN Cable

    If you want to use a USB connection over more than 30m LAN cable. So can run the SDR-Receiver near by the dish and listen to the SDR in the shack. And if you have to ajust the dish you can just plug-in your notebook to the SDR next to dish.


    I can recommend the following product:

    https://www.digitec.ch/de/s1/p…tender-switch-box-7305581


    73 de HB9RYZ

    Wolfgang

  • I have read all the post, but at the end which is the best alternative to octagon otslo that is no more available ? i'm looking to a LNB with possibility to modify with TXCO.

  • A TCXO is not sufficient to be 'on frequency' , lock the LNB to GPS.

    Good alternatives to the 'magic' Octagons are Starcom or other LNB's.


    To put it into another perspective .. I have never had a 'bad' PLL LNB

    (locked to GPS). Octagon, Starcom, Inverto, Goobay, Pollin etc. All perform well when the reference is GPS stable and clean (free from jitter).


    In other words, when you're into the GPS locked world, you don't encounter problems/issues others have (let that be a lesson ; -)

  • Start with simplest approach, try it out and then improve if in need. Any LNB brand of "digital TV" marked LNBs should have a PLL and a XO.
    When getting started with SSB & CW, I do not see the absolute need for a GPS or TCXO governed LNB as long as you allow the LNB to warm up and if you know how to make minor and slow frequency adjustments ;) in your LNB IF receiver.
    My station has just this, PLL XO LNB and TCXO LO in TX converter - and SSB & CW is really easy once warmed-up. Some tuning is needed but at a really slow pace so it does not really impact SSB/CW traffic much.

  • Hi,

    I bought a GLOBO LSP04H from local market.

    It has a 25 MHz XTAL with a 3566 PLL

    I plan to use an external GPS lock from a NEO7 GPS.

    Is it importand to this PLL chip which x-XTAL pin I will use for external clocking?

    I have seen OZ2OE mods but in my case the XTAL traces are below the PCB and I am not sure which 3566 pin goes to each XTAL pin.


    73 de George SV1BDS