•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<

Job Board

About RF Cafe™

Sitemap

Kirt's Cogitations™ #137

These original Kirt's Cogitations™ may be reproduced (no more than 5, please) provided proper credit is given to me, Kirt Blattenberger.

Please click here to return to the Table of Contents.

   Cog·i·ta·tion [koj-i-tey'-shun] – noun: Concerted thought or
                                        reflection; meditation; contemplation.
   Kirt [kert] – proper noun: RF Cafe webmaster.


< Previous                      Next >


Mnemonic for VSWR and Return Loss

At 11.44 dB, both "Pi" and "T" attenuators use equal value resistors for all three branches when source and load terminations are equal. For 50 Ω, the three resistors are all 28.9 Ω in the "Pi" configuration and 86.6 Ω in the "T." For 75 Ω, the three resistors are all 43.3 Ω in the "Pi" configuration and 127.9 Ω in the "T."

Head Sport aG has a new "smart" tennis racket that you'll get a charge out of - literally. Its yoke (the y-shaped area between the handle and the head) is constructed with piezoelectric fibers that generate a voltage when the racket is swung. The converted energy is conditioned and fed to an analog microcircuit and then retransmitted to fibers along the yoke to stiffen it in select locations to counter vibrations. More control over and power to the ball is the result. Professional players are testing the racket now. The International Tennis Federation prohibits the use of batteries in rackets, and this is the ingenuous workaround. Head is also testing a smart snow ski that modulates the torsional stability of the ski along its length to adapt to snow conditions. Trés cool.
Custom Search
More than 10,000 searchable pages indexed.

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger... single-handedly redefining what an engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem!
(Seize the Day!)

5th MOB: My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website