• Salve IK4IDY, questa dual-band e' fatta apposta per avere polarizzazione VERTICALE in salita e circolare destra ( inversione della sinistra ) sul disco, giusto per lavorare il sat come si deve......tutto qui.....73!


    Hi IK4IDY, this dual-band is made to have VERTICAL polarization in ascent and circular right (inversion of the left) on the disk, just to work the sat as it should ...... all here ..... 73 !

  • Hi folks,

    thanks for the positive reactions.

    As soon as the price is fixed and orders can be made, I will announce it here as well.

    The first series of duoband feeds will have only one polarization plane for 10 GHz. But generally two levels of polarization are possible!

    The duoband feed is made of aluminum and it is expected to be anodized.


    Peter, DJ7GP

  • Hi Raf,

    I am just building nearly the same solution and want to insert a small rocket LNB so that this could be used with one dish for RX and TX.

  • The dish is (I believe) 64cm, but the effective surface is the width (will measure it later). I also receive the beacons with this setup, around 20 dB SNR (in 2500 Hz BW),

    so a little weaker than my other setup.


    I tested the setup a while ago while looking at BADR 4 with 11W @2400 MHz and found little degradation, in a sense that the noise floor 'danced' up and down for ca. 2 - 3 dB on my SSB signal.

  • I also use a 130cm dish for RX and 80cm for TX,


    The first reason is easy, if the TX dish is small then easily more RF power could be generated. (If you have the PA ;) )


    On the RX side it is complicated to get better reception.



    73 DB8TF

  • SP9VFD Raf I am just discussing with the company b.e.s.t. in Germany. They have rocket LNBs with PLL!!!

    If you disassemble the plastic enclosure the diameter will fit into the helix. Will get some information from them this week and will post it here. the most issue is to find a dish where the position of the LNB is more away from the boom as usual. for examle here a picture.

    With this it is easy to fit the reflektor for the helix. I have ordered a dish for less than 16Euro including S&H.

  • I am always interested in affordable PLL LNBs but I prefer the 4-port type so I can use one connector for reference input, and still have output for Ham Radio and for normal satellite usage.

    I have one here: SR-3604 or clone (unsure).

    I still need to convert it to external reference input. I'd like to find some solution so that it continues to work from the internal reference when no reference is supplied.

    (so I can watch TV with the reference turned off)

    I would be nice to have the datasheet of the chip (KTD1051 see http://www.ktdel.com/en/Product/Details/1653 ) but the manufacturer does not reply to mail, as seems usual in the far east.

  • pe1chl It looks like that the KTD1051 is similar to RT320 from RafaelMicro. I think you should find 2 chips inside because the SR-3604 is a Quad LNB. The dividing faktor shouls be 390 for low band and 424 for high band.

  • Yes, there are two of them, but there is only a single crystal between them.

    I would like to convert one half to external reference (1 connector for ref in and one for IF out) and the other half to remain on the crystal.

    My hypothesis is that the crystal is used with the oscillator in one of the chips, and the resulting signal (probably one pin of the crystal) is linked to the other chip.

    That is the connection I want to cut.

    But it would be helpful to know the local circuit for the crystal used in standalone mode and which pin is input and which is output.

    (usually the crystal oscillator in such chips takes the form of an amplifier to which the crystal is connected from output to input, and a capacitor on the input)

  • Yesterday I purchased AX techologies Black Buster Quattro and I am really sad.

    http://axtechnology.shop/en_US…-QUATTRO-BLACK-BUSTER/161


    I wanted Quad, but quattro is OK. Duad delivery on every output enythig what you ask (by manipulating polalry voltage and tone). Quattro deliver on every output own signal: Hor-Low, Hor-High, Vert-Low, Vert-High. so, need to connect sdr and minitouner to correct output and unused (high band) connectors can be used for LNB supply and Ext Ref clk in.


    The biggest problems it that this LNB don't have PLL and quatz. They are using ceramic oscillators. So no ext ref clk in possible. We careful before purchasing LNBs.

    Here are few pictures of my problem. Be smart and don't make my mistakes.




  • I will try it.

    PS: Thanks to YL3JG, I have PLL locked SDR receiver in GNU Radio.


    This is only concept right now, but it nicely lock to carrier. Later I will test it with existing Es'Hail-2 beacon.



  • Some time ago I purchased AX technology Opticum Twin Black Buster LNB.
    http://axtechnology.shop/en_US…CUM-TWIN-BLACK-BUSTER/160


    Absolutely different internals compared to Quattro LNB. I don't have PCB picture, but it looks 90% like this Octagon OTSLO 1609 LNB, except tah Opticum don't have 10.7-12.75 GHz BPF and different PSU doide case, so I hope it will work nicely on 10.49 GHz. So this LNB will be starting point for P4A NB and WB.


    http://www.pabr.org/radio/lnbl…neup.en.html#OTLSO%201609