Advertisement

As is always the case, we've been busy adding plenty of new stuff to Microwaves101. We ain't been slack, Cap'n Walker!



New for March 2021: We are now done with the month that most people don't pronounce correctly, a huge relief for those of us with misophonia, a condition where certain noises can drive you crazy...  Now for March, can we all agree to try to remember that "heighth" is not a word?

Celebrate International Women's Day (March 8th, not "8") by reading about trailblazing women in history, here.

Meanwhile, what's new at Microwaves101?

  • We added a new page on wire-over-ground transmission lines, to back up our on-line impedance calculator. Here, we explain the exact closed form calculation and the approximate formula that just about everyone uses.  We also wish to clear up the manner in which dielectric materials are accounted for. We also provide the capacitance/length and inductance/length calculations, all with the help of a Japanese web site where someone smarter than us works.

  • On our where-are-they-now page, we made some notes about the RCA Sarnoff Center thanks to Murat.  We also added  most of the capacitor suppliers that are part of  of what is now known as Knowles Precision Devices: Dielectric Labs, Novacap, Johanson and Compex. Thanks to Jackson!

  • We scanned and added the entire Bedford Automated Artwork manual, which was first discussed last month on our BAA page. Check it out and see what you missed by not working at Raytheon Missile Systems in the early 1980s. The link to the manual is near the bottom of that page. Thanks to Brenda for scanning all 133 pages!

  • Regarding BAA, we correctly predicted that someone was going to email us and say "we had that capability years earlier".   John send us some inputs on MAGIC, Electric and LLAMA, which we added to the top of our history of microwave software page.  Apparently some of these programs are still in active use!

  • Added a book review of RF Circuits and Applications for Practicing Engineers, by Mouqun Dong. This book is aimed at amplifier designers that use printed circuit boards, but would be useful in other efforts.  He provides rigorous stability analyses, shows you how to develop matching network design on the Smith Chart including Q considerations, and discusses quite a few topics which are (gasp!) not covered very well on Microwaves101.  All this is followed up with examples of amplifiers. If you are looking to upgrade your library of practical design references, consider picking up a copy today!

  • We have a guest "Unknown Editor" this month, who discusses all things COVID-19. If you want to express your point of view on our web site, contact us... there's no guarantee we will post your rantings, especially if you are what George Orwell might have called a "wrongthinker," compared to any opinions you might find ever-so-slight hints of around the Microwaves101 website.

  • We've added a nice picture of Bernard Schiffman, sent in by his daughter, in our Microwaves Hall of Fame. Schiffman's name is associated with a type of phase shifter.

  • In February we created a page as a home for two videos starring John Shive.  Born in 1913 in Baltimore, Maryland, he spent his entire technical career at Bell Labs.  Bell Labs produced two videos in 1959 starring Shive, demonstrating two "wave machines."  Shive's first video, Simple Waves,  features a very long "Slinky." Using props such as the motor from a phonograph and a mousetrap, Shive answers questions such as: does the speed of a wave depend on properties of the media it is in? Will a wave travel with a constant speed in a uniform media? How does the speed of a wave depend on its size (amplitude) and shape (pulse width?)  Shive also introduces the more complicated torsional wave machine, a true thing of beauty, which is featured in the second Shive video, and appears farther down the page.

  • We're always fixing typos and making fixes of one kind or another. We fixed our Marchand  balun page thanks to John C. Figure 13, the impedance variation across frequency, was incorrectly annotated.  Notice something not-quite-right? Let us know!

  • Meanwhile, on our discussion board, we've got some questions that need YOUR answers. Here's a discussion on the maximum impedance of a transmission line.  Here, Bob want to talk about using a YIG crystal in a detection scheme. Shubhamm is looking for advice on the widths of resonators in a stripline filter. Thomas is looking for advice on circular waveguides. Jim finally  got some advice on a source of silver-plated screws for tuning waveguide (thanks to Desert Sage!). Pop on over to the discussion board to register and sign in, then chime in on existing threads, or start your own topics. Our new user approval process is quick and anonymous, blocks most bots, and eliminates spam by more than 99%. At least that's what the sales rep told us...

Attention forward thinking microwave marketeers: check out information on advertising with us. Sponsorship information is but a click away...

As always, we want you to sign up for the MW101Stuff newsletter, or submit a photo for our Microwave Mortuary. We'd love to hear from you, whether you have nice things to say about Microwaves101.com or just want to tell us how we've ruined your life.

 

 

 

Advertisement