Here I show how I designed a coaxial cavity bandpass filter. The method of Dishal is employed, using the k and q values.
Design of such a filter is impossible without a 3D EM simulation software like CST, which is what I used for this project.
Continue reading Design of a Coaxial Cavity FilterIn the service manual of the HP 8753C, I read something about a cavity oscillator which is used in this instrument. Later, I read some article in the HP Journal, also about cavity oscillators. Time to build my own!
Continue reading Cavity OscillatorAt a former employer, they threw away a HP 4195A network analyser. The reason was because it had some problems with its internal source. I kept the unit for a few years and always was afraid of opening it and repairing it because I thought the potential to further damage it was too high. But now I tried to repair it and it worked 😀
Continue reading Repair of a HP 4195A Network/Spectrum/Impedance AnalyserJust for fun I made a couple fractals with Matlab.
Continue reading Fractals with Matlab or Octave