Reader Letter: Waveguide
May 4, 1964 Electronics Magazine

May 4, 1964 Electronics [Table of Contents] Wax nostalgic about and learn from the history of early electronics. See articles from Electronics, published 1930 - 1988. All copyrights hereby acknowledged.

This letter submitted to Electronics magazine by reader Fred Standish really should have been saved for the next April issue. He writes concerning an attempt to mathematically describe the three-port circular-to-rectangular waveguide transition for the pictured configuration. If I remember correctly, the first time I saw that optical illusion was sometime in the early 1970s. The drawing showed Alfred E. Neuman (the red-haired, freckled-faced "Me Worry? guy from Mad magazine) attempting to don a pair of pants (a triplet of pants in that case?) sewn to resemble the three-legged configuration - known unofficially as the "Impossible Trident." I was in my early teens at the time and though it was awfully clever. After doing a little research, I found that the first instance of the Impossible Trident in Mad magazine was on the cover of the March 1965 issue (#93). The Impossible Trident was created by D. H. Schuster, an American psychologist, who based it on an advertisement he saw in an aviation journal. It was first published in The American Journal of Psychology in 1964, although some challenge the assertion since everyone was glomming onto the figure at the time..

Reader Letter: Waveguide

Here at Litchfield we have been working to establish the design and performance factors for a three-pitched femto waveguide. We are trying to establish the relationship between the circular cylinders at left and the rectangular-prism resonant cavity. So far we have had flat response through the top cylinder and low-pass response towards the bottom cylinder. The mode lattice has been difficult to establish for the left center cylinder, although it looks better than a Moreno cross guide coupler. Even and odd-mode impedance of parallel slab line has given us trouble. Where can I find data that will establish the susceptance of symmetrical irises?

Fred Standish

Litchfield, Conn.

• Try pulling a few more legs.

Posted May 27, 2019