AMSAT-DL Down Converter v3d

  • Hi all,just hooked the V3d (GPS version) up for checking it out.The frequency offset on the 10Mhz output I found to be 18Hz above 10Mhz which seems to be normal.Has anyone tried to connect the Leo Bosnar source instead of the GPS modul? Would the 10 Mhz output now be exactly on 10Mhz or would there be still an offset required?How critical is the level and waveform for such an external input signal?

    73 Karl

  • Hi,

    i just tried to feed 10Mhz external to the Pins described in the manual. No joy. The signal on the WB-output is 24.040ish and will not move wether the external source is connected or not. The source delivers 10mW@50Ohm. Connection was: shield to Pin2, 3&4 jumpered, signal to Pin5. I think that's right?

    Found that 10Mhz and 24Mhz are dead on frequency with gps-module in place but no GPS-Antenna connected, but 22Hz high on 10Mhz and 56Hz high on 24Mhz with GPS-satellites found.


    Looks like results are good when no gps-module in place AND unit is jumpered for 25Mhz. WB-out shows 25.0000.000, 10Mhz-out shows 10.000.000Mhz. Firmware is 1.0 . Is there a newer firmware?


    Changed the title of the thread from “amsat down converter v3d” to “AMSAT-DL Down Converter v3d”.
    • Official Post

    Our excellent development team has decided to provide and publish the source code for the firmware of the AMSAT-DL QO-100 up- and down-converter under GPL-3.0 license.

    You can find it in our repository:

    So if you have the appropriate possibilities, you can flash the current firmware yourself... the corresponding binaries can also be found in the archive.