No Signal RX

  • Hello Riri,


    sorry I did not anwer your last 2 questions:


    I am not 100% sure how your LNB looks like but many LNBs from AMSAT-DL

    were LNBs with 2 outputs (one for the NB transponder and one for the WB transponder).

    The reference frequency input was at the WB transponder output port.

    Thus if you want to use such an LNB for NB operations you have to supply indeed a supply
    voltage to both ports and in addition supply the reference frequency for the PLL in the LNB

    on the WB output port. By choosing the supply voltage you can select the polarization e.g.
    12-14V one polarization and 14-18V the other polarization. You can indeeed supply the same
    voltage e.g. 12V to both outputs and then get on both output ports the same polarization.


    I do not have a SG labs transverter but I think they are of very good quality and the only
    configuration you need to make is setting the local oscillator frequency (to chose which
    part of the 13cm band you want to operate e.g. 2320 MHZ for EME or 2400MHz for satellite
    uplink). I am not aware of any modifications you need to do at this transverter but maybe
    other can chime in who are using such a transverter.


    Kind regards


    Matthias


    Homepage DD1US

  • Hi Riri, there are many people here who would like to help you but we need to understand what your problem is. Is your antenna aimed well at the Es'hail-2 satellite? If you have a commercial TV-Sat receiver you can try tuning this TV transponder which arrives very loudly in your area. Eshail-2 beam MENA freq. 10770 Vert. DVB-S2 8PSK 27500 3/4. This means supplying 12 Volts to the LNB to have vertical polarization. Once the antenna is aimed well at the satellite the rest becomes easier.

    As you were told for the transverter you must ensure that the local oscillator frequency is set to 1968 MHz.

    1968+432=2400 MHz. So you will have to provide the transverter with a 432 MHz signal (1 watt is enough) to have 2400 MHz output. Please if you still have problems try to explain your difficulties better

  • Thank you Guys, my installation is a transverter from SG lab Transverter 2300 / 432 MHz Transverter V1.4

    the LNB is DJ7GP V2 2.4 Ghz & 10 GHz antenna with LNB modified 24 Mhz AMSAT DL.


    The antenna is aimed well at the Es'hail-2 satellite i can receive the signal on a simple LNB, but when i use the


    DJ7GP V2 2.4 Ghz & 10 GHz antenna with LNB

    modified 24 Mhz AMSAT DL there is no signal should i supply the 2 outputs voltage like Matthias said, i will try today.


    Thank you for the help.


    73, Riri OD5RI


  • Hello Riri,


    now its clear.


    The Bamatech modified 24 MHz AMSAT DL LNB needs a 24MHz reference frequency......


    Original text from Bamatech website:

    Version 2 improves the left hand circular polarization (LHCP), has more mounting space and a new lens for better reception gain on 10 Ghz.

    This version has a modified PLL LNB head to have a 24 Mhz input on the second F connector, for use with the AMSAT DL downconverter.


    Without this 24MHz reference signal it did not work!


    73 de Robert, DD4YR

  • Yes,

    the easiest or quickest way would be to replace the LNB with a standard LNB.

    Otherwise, it need a stable 24 MHz source that generates the reference signal. The AMSAT downconverter has a GPS stabilized reference built in.

    In your case, an external GPSDO (GPS stabilized oscillator) could provide a remedy and ensure a stable reception signal.


    E.g. from Leo Bodnar. https://www.leobodnar.com/shop…cPath=107&products_id=301


    73 de Robert, DD4YR

  • Riri,

    A somewhat tricky, but simple and inexpensive option would be to tap the 25 MHz oscillator frequency from a standard LNB and feed it via cable to the second F-connector reference input of the Bamatech LNB. In other words, use a cheap LNB as an oscillator for the reference frequency.



    The BullesEye LNB offers something similar. It has prepared the reference frequency at its second F-Plug as output to feed other devices. (red)



    73 de Robert, DD4YR