Transceiver & Receiver

  • Selection of analog and/or digital devices

    Transceiver & Receiver


    Transceiver (analogous)

    Many OM's already have an all-mode multiband transceiver such as IC-7100, IC-9100*, IC-9700*, TS-2000*, FT-991, FT-857D, FT-817/818ND or similar devices for SSB operation on 2m and 70cm. Two devices, one for RX and one for TX, can also be used. Even working vintage devices from the time of AO-10 and AO-13 such as an FT-736/847 or the duo TS-711/811 can be used again. These devices are also full-duplex capable for satellite operation, as are the newer types marked above with *). The only disadvantage with these devices can be that you have to calculate the uplink/downlink frequencies yourself. However, with programming skills, this is a challenge.


    QO-100Rig_klein.jpg


    In order to avoid harmonics, it is advisable to use 10m or 2m for reception using a Down-converter and 70cm or 23cm for transmission using an Up-converter.


    Receiver (analogous)

    With a broadband receiver, the IF of the LNB can be received directly, no Down-converter is required. But here, too, the real reception frequency of the transponder is not displayed.


    Receiver for DATV

    The frequencies used are not standard satellite frequencies and the bit rates we use for ATV are lower than commercial satellites. The choice is limited, but attempts with an Octagon SF8008 satellite receiver have been successful.


    To receive the horizontally polarized broadband DATV transponder, you need a DATV receiver that can receive 741 MHz to 749 MHz. Unfortunately, this is outside the normal frequency tuning range of a standard consumer digital TV set-top box (STB). Therefore you either need an additional up-converter to shift the IF frequency upwards and to be in the tuning range of the STB in the L-band between 950 and 2150 MHz. An original Astra frequency extender Global ADX-Plus works. Alternatively, you can change your PLL LNB by changing the 25 MHz reference quartz to 26 MHz to produce an IF output above 950 MHz.


    However, there is a USB tuner, the MiniTiouner, which was specially developed for ATV and covers 143 MHz to 2450 MHz by default and is suitable for receiving Es'hail-2 and a number of amateur bands without modifications or additional up-converters.


    The other reason why the MiniTiouner is the preferred solution for receiving the DATV transponder is that most DATV transmissions use RB-TV with a reduced bandwidth of less than 1 MHz - so far 90% of DATV transmissions are on OSCAR -100 in RB-TV. A standard STB, other than the model mentioned above, will not receive these RB-TV signals, but MiniTiouner is designed to receive these signals of less than 100 kHz bandwidth.



    Transceiver (digital/SDR)

    Adalm-Pluto:

    Analog Devices' ADALM-PLUTO SDR is actually an active learning module (PlutoSDR) and provides an introduction to the basics of software-based radio (SDR), radio frequency (HF) and wireless communication for electrical engineering students.


    The module is connected to a Windows PC via USB. The software SDR Console from Simon Brown, G4ELI, is available free of charge on the Internet and allows full duplex operation via QO-100. Since the Adalm-Pluto only has a tiny output power, a preamplifier is required. The module is not shielded, so it has to be installed in a housing beforehand. Mathias, DD1US, describes the installation in an HF-tight housing in his detailed article (in German). Modifications for QO-100 operation are being developed by Eduardo, PY2RN.


    LimeSDR:

    LimeSDR are mini boards from Crowd Supply with software-based radio (Software Defined Radio, SDR) and represent a hardware platform for the development and prototyping of high-performance and logic-intensive digital and RF designs.


    The mini board is connected to a Windows PC via USB. The software SDR Console from Simon Brown, G4ELI, is available free of charge on the Internet and allows full duplex operation via QO-100. Since the LimeSDR only has a tiny output power, a preamplifier is required. Ole, OZ2OE, measured the output power of his LimeSDR and made the data available. The module is not shielded, so it has to be installed in a housing beforehand. Dietmar, DL2SBA, describes the installation in an HF-tight housing in his article.


    Receiver (digital/SDR)

    For NB-Transponder:

    With an SDR receiver or SDR dongle, the IF of the LNB can be received directly, no receiver converter is required. The receiver is controlled by the SDR Console software from Simon Brown, G4ELI, and is available free of charge on the Internet. The actual reception frequency of the transponder is displayed through the configuration. The reception frequency is also stabilized and no longer runs away with an unmodified LNB.


    For WB-Transponder (DATV/MiniTiouner):

    Standard SDR software and hardware do not as standard receive DATV signals however, there are 2 programs for the advanced user which may work at some symbol rates:



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