Category Archives: Construction

ircDDBGateway Basics

Over the past week or so, I have been playing around with DStarRepeater and ircDDBGateway to learn a bit about DSTAR repeaters, given the progress GB7KH‘s NoV is making. I have made a simplex hotspot with my FT817 and a soundcard interface, although I can see that there is certainly room for improvement. I have ordered a DVRPTR_V1 GMSK interface which has been dispatched so that will replace the soundcard, lowering the CPU load. I am to have the system set up on a Raspberry Pi 2 B, which was released yesterday (maybe today actually). I think I now understand how to tune up those Chinese notch filters, too.

DVRPTR_V1 inside board

144 MHz 1.25 kW Amplifier

Over the weekend I worked on my 1.25 kW solid state PA based on F1JRD’s design from Dubus using a MRFE6VP61K25H. I bought a complete kit at the Friedrichshafen Hamfest 2012 from F1JRD and F5CYS and built it up late 2013 but due to problems, I never had more than around 40W output. This weekend, with a new set of capacitors from ATC I rebuilt the output matching and fired it up once again. With my 1kW/50V power-supply I can get around 600W output, which his more than enough. This is still a work in progress, but things are moving forward with the project.