:: Project Swift ::

Mark (Darkside) has kindly shared his design for an antenna diplexor with us.

An antenna diplexer or RF diplexer is a unit that in one application can be used to enable more than one transmitter to operate on a single RF antenna. Sometimes these units may be called antenna duplexers. Typically an antenna diplexer would enable transmitters operating of different frequencies to use the same antenna. In another application, an antenna diplexer may be used to allow a single antenna to be used for transmissions on one band of frequencies and reception on another band.

In a truely international effort Mark e-mailed the Gerbers for his design across which were dispatched to Seeed Studios in China. A few weeks later and 10 shiny diplexor boards had arrived and were soldered up:

These will allow Swift to use just one antenna whilst retaining the ability to transmit on 2 meters and 70 cms.

Thanks for Darkside for the assistance on these.

After noting numerous faults in the Swift Rev1 it was decided to redo the PCB layout. This resulted in Swift Rev2 :

Each part of the board was soldered then tested starteding with the power, the ATMega644, then the GPS, the BMP085 and finally the radio module.

As my coding skills suck Phil connected in (via IPv6 for extra geek points) to a VM Running Linux. He compiled and uploaded various testing code to the prototype board to check its operation. The good news is all components, even the scary to solder BMP085, seemed to be working as expected.

I was really chuffed with the way the boards have turned out and was a little sad to post the completed board off to Nigel for further coding. A second board was made up, tested and posted to Phil.

So over to the software team now !