Unun vs. Balun

I think you could make a palindrome starting with with "Un balun y un unun..."  I don't think I'm the right man for that task. But I can tell you what they are and what they are for. balun is a difficult word to research being both a surname, an engineering term, a city,  and a slang word in Spanish meaning  balloon. They are both types of transformers and sometime I'll have to write a post about those as well.

• Balun [bal-uhn] noun

A device that allows a symmetrical antenna to feed an asymmetrical line. It is balancing an unbalanced input. It's a portmanteau word combining balanced and unbalanced. In it's early use it was almost always called a "balun transformer." We have largely dropped "transformer" from it's paired use. Balun already intimates transformer.  I hae fourd it used in catalogs from 1950, and it appears to have come into use in the decade prior.  The earliest use I found was in a 1947 catalog and was describing a "Balun bazooka" then described it as "a device for transforming from BALanced Line to UNbalanced."  [Their own capitalization] the timing leads me to believe that the contraction is military in origin. Here are a couple confirmed early uses:

Very High-Frequency Techniques, Vol. 1 - Harvard U. - 1947
"For a fixed position of the balun short-circuiting bar, the induced voltage E tends to increase with the frequency"

Hewlett-Packard Journal , Volumes 1-13 - H.P. Company  - 1949
"When this condition exists, there is theoretically no phase error introduced by deviations in balun legnth."

Radio Engineering - Terman, Frederick- Mcgraw-Hill - 1947
"At the same time, the balun does not introduce an unbalanced load to the balanced system, since the impedance across 2-3 approaches infinity..."

• Unun [uhn-uhn] noun

A device that allows an unbalanced antenna to couple with an unbalanced feed line. It's also a portmanteau word combining Unbalanced with Unbalanced. It's a less common device and more than likely a pun based on balun. This term has a much more recent vintage. I can't find it in any texts before about 1995. The earliest reference I found was in Issue 72 of the ARRL handbook for the radio amateur.