WA3TFS SDR Upverter Design

From Land Boards Wiki
Jump to navigation Jump to search

WA3TFS Upverter P1874-720px.jpg

Features

SDR up-converter/receiver shifts HF (0-30 MHz) frequencies up by 100 MHz. Used to listen to HF frequencies on an inexpensive RTL-SDR module.

Schematic

WA3TFS Upverter Schematic.PNG

Pass Filter

  • 9 turns on FT37-2 = 0.3 uH

WA3TFS Upverter Inductor.PNG

  • LTSpice Simulation
    • 1-100 MHz

WA3TFS Upverter Pass Filter.PNG

  • LTSpice Simulation
    • 1MHz-1GHz

WA3TFS Upverter Pass Filter 1MHz-to-1GHz.PNG

Software

Build

  • Nice silver mica caps
    • My kit was missing the center cap of the band filter (150 pF)
  • SBL-1 mixer
  • 30pF cap installed in J_A to J_B marked 300
  • Build was tough due to very small pads on the PCB
    • Particularly tough to solder ground pads
    • Pad shapes were not round so less area to set soldering iron
  • Is LO drive more than 7 dBm?
  • Pin 1 orientations on the mixer and oscillator "backwards" from other board legends
    • Pin 1 shown in red

WA3TFS Upverter pcb r11.jpg

Wiring

WA3TFS Upverter Wiring.PNG

Enclosure

WA3TFS Upverter P1878-720px.jpg

WA3TFS Upverter P1880-720px.jpg

Videos by others