A while back I created two circuit board designs to learn Upverter, but also gain some experience in laying out circuit boards. SeeedStudio will sell you ten 5×5 cm circuit boards for about USD$15 shipped.
I decided to create a SA602 RF mixer board and a separate crystal filter board to go along with it. The mixer board is built with multi-purpose implementations in mind. For instance, you can configure it as with a crystal, or a LC oscillator, or add a varactor. The inputs and outputs have multiple through-holes for using a transformer or capacitors.
The crystal filter board supports four crystals and has an optional configuration of using varactor’s for variable bandwidth.
I sent both designs to SeeedStudio (first time I used their service). I was impressed that I could download the Eagle files from Upverter and send them to Seeed without changing file names or doing anything.
