A common complaint you will hear about radio amateurs is that it is a harassment of a checkbook. Of course, you can work with the amazing DX if you spend $ 20,000 on a high-end radio, a large antenna and related components. The reality, however, is that because it is such a versatile world, there are many ways for it, of which the operator with the shiny platform brings only one.
On the often used HF and VHF bands at the lower end of the radio frequency spectrum, you will definitely find fans of the checkbook of the type described in the previous paragraph. But as you climb into the microwave, there are no new shiny radios on the market, so even a licensed licensee has to plow his own furrow and build his own station.
You may think that this will remain a check mode of a different type, as exotic microwave devices are not always cheap. But in fact, these tapes have a long history of extremely inexpensive construction, in which skilled design and construction play a role, as well as intelligent reuse of components from satellite TV systems and Doppler radar modules. And this is a project next time, which is our topic today [Peter Knol, PA1SDB] there is converts a modern Doppler radar module as a transmitter for 10GHz or 3cm amateur band (Google Translate version of Dutch original). The best thing about [Peter]The project is the price: these modules can be obtained for only three euros.
Years ago, a Doppler module would use a Gunn diode in a waveguide cavity and a small horn, usually with an adjacent mixer diode for reception. Its modern equivalent uses a transistor oscillator on printed circuit boards, with a dielectric resonator and a set of antennas. There is also a simple receiver on board, but since then [Peter] uses a converted satellite LNB of ten euros for this task, it is redundant.
It guides us through the process of adjusting the frequency of the module before showing us how to mount it in the main focus of a parabolic antenna. FM modulation comes through a very old-fashioned power transformer. He then considered installing an SMA connector and using it for more advanced antenna settings before experimenting with the attenuating properties of various substances. Overall, this is a fascinating read if you are interested in the simple design of a microwave oven.
The result is not the most achieved 10 GHz station in the world, but it performs adequately at its extremely low price, given that it has registered a 32-kilometer contact with it.
While we cover our fair share of amateur radio stories here at Hackaday, it’s fair to say we haven’t seen much in the microwave. However, if you think we have been fired in this area, we can direct you to our recent coverage of microwave radio made of diamond?
Through Southgate ARC.