DBS Downconverter
I found an old satellite TV downconverter in the garage today. It drew me in and compelled me to disassemble it. One of the wonderful aspects of microwave circuits is that classical layout strategies persist. This board has a single layer of traces over a ground plane: everything is laid-out in one plane, quite visible and tangible (perfect for learning, I might add). The waveguide that feeds the antenna has two probes that bring the signal onto the board. You can see the I and Q channels and their respective LNA stages, the dielectric resonator oscillator in the center of the board, hairpin filters, mixers, bias lines and matching sections. Beautiful.
