The art of porting cylinder heads, whether by hand or by CNC machine, is a valuable part of blueprinting detailed engine builds or overhauls, and surprisingly subtle changes can determine how efficiently the engine will breathe.
One of the final steps in getting your avionics suite to work is installation of some sort of antenna to capture various radio frequencies. Failing to choose the right antenna and install it properly can compromise the whole installation. Rather than focusing on the intricacies of antenna design, the author discusses the merits of internal versus external for particular equipment plus where to place them; by Stein Bruch