This page documents the building of G3XBM’s 472 kHz transverter by G8OCV and myself. We started experimenting with 472 kHz as soon as the band was available having just missed out on 500 kHz NoVs. If you look on my 472 kHz page you can see some of our other projects.
Roger, G3XBM, provides a schematic for his transverter. If, like us, you have the facility to make printed circuit boards then you may well find the following schematic, board masks and Gerber files of use. To make life easier when designing the circuit boards, we duplicated the schematic into our software. There are two diagrams, the transverter (left) and the optional filter board (right). Click on these to enlarge.
|The Transverter Schematic||Optional Filter Schematic|
We then come up with the following PCB design, which was designed to fit into a diecast metal box, as seen further down; the box serving as a heatsink for the FET. The images here are at 600 DPI, which should be supported by any modern printer/software (I recommend GIMP, open the file, print, set 600dpi as the resolution, cross fingers). Alternatively, there are PDFs links below the images (print at 100% on A4).
|Copper Mask PDF||Silk Screen PDF|
|The Transverter Bottom Copper (600DPI)||The Transverter Component Silk Screen (600DPI)|
Finally for anyone who prefers to mill boards with CNC machines, here are the 472kHz Transverter Gerber/Excellon files.
Below is a picture of our first attempt, boxed in a dycast box. It works well!
When intially testing the transverter I had arranged a few skeds with Dave (G7UVW) and John (M0UKD), who has also built a 472 kHz transverter. When I had finally built enough confidence and got my antenna tuned, I answered G3XIZ calling CQ. I was expecting much, but he came straight back to me, correct callsign, no problems at all! Reports and were exchanged before Chris (G3XIZ) had to head off for tea! I took a printscreen of the QSO from FLDigi (I’m hopeless with CW and need a computer’s help!).