ON1BES Labo 2016 Semi-automatic SDR-Upcoverter v2.0
Only English version
The smallest SDR Upconverter you known? Let me know!
This version 2.0 is an alternative version of my previous SDR HF Up-converter 1.0. The objective was to replace the passive mixer by an active, and then we can even compare with the SBL-1 in the previous version. And because there was already a power supply needed for the crystal oscillator, i choose to use the mixer IC SA602. It was easier to obtain than the IE 500 or SBL-1, which is anyway quite large, and not suitable for SMD placement.
Moreover, there is a SMD relay to automatic switching from HF to VHF if you disconnected the supply voltage (unplug the USB).
The entire board is designed for SMD components, so that ready-made available coils can be used. That was a bit of searching on the Net, but ultimately still went well. The filter values were then also be adjusted, in order to be able to use default values of inductances and capacities.
The schematic :
As to be expected, immediately after building, and connecting the cables to the antennas, it schould been working fine.
In this version, cheap RCA inputs chassis are used, and that is not a problem even on HF and VHF .
From the original stock-antenna that was supplied with the SDR stick, is only the coax cable reused here. This must cut on the antenna base, and directly soldered on the output mark of the up-converter board. So, the other end can be connected directly to the SDR stick, regardless of whether you have a MCX plug or a 75 Ohm PAL antenna plug.
For receiver results and screens , refer to my other page : HF Upconverter V4.0
mail: on1bes Scarlet.be