[NLRS] Boradwall Waveguide slots for antennas

[Dr. Gerald N. Johnson]

I know there has been some mention in references I have about round ends 
vs square ended slots, though most of the computation appear to be based 
on square ends to the slots and no thickness to the waveguide walls. Is 
there any literature showing a difference between the resonances and 
radiation of round vs square ended slots?

Then is there any that allows for the slot in the inside of the guide 
being a different length than on the outside, as it would naturally be 
from cutting the slots with a metal circular saw blade? Or does all the 
literature presume all slots will be squared up by hand after the 
milling operations. With copper not a fun material to cut slots in with 
an end mill because its so gummy and grabby, I'm thinking cutting with a 
fine toothed saw blade would make much smoother slot walls and destroy 
way fewer cutting tools. Filing isn't much fun either with a file small 
enough to fit in a 10 GHz slot. The stroke can't be very long and the 
file has to be thin and weak. I have a large supply of 3" and 4" 
diameter metal saw blades that I can use, if the slot resonance and 
radiation aren't messed up by sloping ends on the slots. I also have 
collected a few 3/4" and 1" diameter but those won't get the ends 
perfectly perpendicular to the surface and have very coarse teeth 
compared to the bigger ones.

73, Jerry, K0CQ