A Simple Harmonic Mixer/Antenna Feed for 47 and 76 GHz Experiments

摘要

Just in the last year, members of the SDMG have started experimenting at 47 and 76 GHz. The issues for those bands seemed to be providing a clean LO signal and coming up with a harmonic mixer and antenna with feed. We were fortunate to purchase a quantity of two models surplus Verticom synthesizers which cover about 9-10.7 GHz and 12.6-13.3 Gz with very low phase noise and are locked to an external 5 or 10 MHz reference. These units have provided considerable flexibility while getting our feet wet on these bands. With the LO source issue resolved , I decided to look for approaches to build harmonic mixers from materials available to our group in quantity. At the time, I had not yet been fortunate enough to put my hands on DB6NT harmonic mixer boards or one of the Phillips or other modules appearing on the Amateur scene. Even with one of these mixers, I'd have needed to come up with a suitable dish and feed. Falling back to using Qualcomm surplus as usual, I came up with this simple and crude way of getting on the 47 and 76 GHz bands. This approach is really intended as a means to get started easily as it does have a number of potential drawbacks. It's simple , does work ,and I hope to have several SDMG members operational for at least the basic 1 km contacts during the 2003 10 GHz & Up contest.