When I'm designing a Cassegrain antenna for mmWave radio, the main dish is a parabola, but the deep ones from Edmund Optics are very hard to illuminate because they have a focal length to diameter ratio of 0.25, which is WAAAAAY less than most dishes. Solution is to put a hyperboloidal subreflector with its rear focus coincident with the prime focus of the parabola, and the front focus of the hyp is where you put the feedhorn. I made the rear so it can take a very fine adjustment thread
@jmorris Working on a full range of items for sale, SMA, 2.92, N and TNC to waveguide transitions, waveguide to waveguide tapered transitions, Cassegrain and Gregorian subreflectors for multiple dishes and frequencies, directional couplers, waveguide and coaxial filters, Edmund Optics dish mounts and focus slides and hopefully some high precision machined dishes for mmWave, parabolic but also axially-displaced ellipse types, lots of feedhorns and lenses. No time to sleep or make Youtube vids!