Building a Septum Feed for 23cm
The two sides are guillotined and folded on a Brake Press. The Septum is cut from sheet and
filed to the exact shape detailed by OK1DFC. The two monopoles are turned from 6mm
diameter Brass and cut to approximately ¼ wavelength, these are adjusted for the best return
The two tuning capacitors in the back plate have very little effect on the tenability of the feed and
can be left out without any detrimental effect.
The Choke can is cut from sheet and the outside ring is cut and shaped as shown. It is then
riveted to the base plate using Blind rivets. The choke can is then bolted to the feed and
grounded to the waveguide in as many places as possible.