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RF Cascade Workbook for Excel

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About RF Cafe™
"Serving a Thoughtful Blend of Yesterday, Today, and Tomorrow™
- published by the North Carolina sole proprietorship business registered as "Kirt Blattenberger" -

Kirt Blattenberger™ | Greensboro, NC

Copyright | Disclaimer | Acknowledgements | kirtrfc@aol.com

The RFCafe.com™ website is part of the state of North Carolina sole proprietorship business registered under the name of "Kirt Blattenberger," and reports income and expenses to the State and Federal governments accordingly.

Please support RF Cafe

Inflation has taken a big chunk out of my income, so anything you can do will help. This DONATION page  includes sending Gift Cards from various stores.

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in Morse Code

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RF Cafe™ QR Code

RF Cafe - QR Code... scan it with your phone!

This is the QR scan code for the RF Cafe™ website. Scan it with your phone!

RF Cafe™ Videos

View the YouTube RF Cafe Intro video

RF Cafe™ Intro Video

View the RF Cafe security Task Force training video

RF Cafe™ Security Task Force Training

USAF Radar Shop

Here is some info on the air traffic control radar I worked on in the USAF, and also a large collection of photos and names of other radar techs.

Reciprocal Links

If you are kind enough to provide a link from your website to RFCafe.com and want to use an image or just text, please consider using one of prepared formats presented here for simplicity. A large selection of commemorative logos are available.

Custom RF Cafe™ Gear

Please support me with a purchase of custom RF Cafe™ products. T-shirt, sweatshirt, coffee cup, mouse pad, baseball cap, etc. Just 50¢ over my cost.

The Internet might be "free," but I can't live for free. Please be as generous as possible. Thanks!

 - RF Cafe


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* Please Note

For business registration and tax purposes, the official name of this website with the title of "RF Cafe" is simply my Legal Name, "Kirt Blattenberger." There is no "Doing Business As," "Assumed Name," or "Fictitious Name" associated with the website.

technodrama™ is a term coined by Kirt Blattenberger to describe short stories of the type written by Karl Kohler, John T. Frye, and others who wrote for electronics and science magazines in the 20th century.

Kirt & Melanie Blattenberger at RF Cafe™ corporate headquarters

Melanie and Kirt Blattenberger, RF Cafe™ staff, in 2007.

Here some archived homepage screen captures of RF Cafe™, compliments of the Wayback Machine™

RF Cafe* really began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time, and not much was available in the form of WYSIWYG editors; in fact, my early pages were written using Notepad. After a couple years of adding material to the website, I noticed that the hit counter would sometimes record a hundred or more hits in a single day, which clued me in to the reality that other people were finding my site useful. E-mails began arriving with suggestions, corrections, and even a few compliments.

July 19th is officially "RF Cafe Day!"

Please click here to find out about advertising on RF Cafe™.

That was enough to convince me to expand the presence, so I hijacked web space from my kids' AOL area for storing files, and linked to them from RF Tools. On July 19th of 1999, I purchased the rfcafe.com domain (and also rfcafe.net) and launched the RF Tools content as "RF Cafe™." The RF Cafe™ name was chosen due to its brevity for typing, its simplicity for remembering, and, perhaps most importantly, because it hints at my appreciation for a good cup of coffee. Besides, names like "e-<Something>" and "<Something> Cafe" were in vogue at the time.

RF Cafe™ Established on July 19, 1999After many years of handling webmaster duties myself, the demand increased to the point that I could not handle all the many additions and revisions that are performed on a daily basis. I have always had a fulltime job while running RF Cafe™, so maintenance consumed the evenings and a good part of the weekends. I scan the Internet daily for interesting headlines, write many commentaries, research day in history items, create the crossword puzzles, constantly search for and generate new content, write spreadsheets and other software, design advertiser ads, choose good books for display, manage the overall website format, and everything else that requires a more in-depth engineering knowledge. Finally, in April of 2007, I left RF Micro Devices (RFMD, now Qorvo) after more than five years with them to work at RF Cafe fulltime. It has been twelve years now (as of 2019), and I truly wonder how I ever got enough done because even now I spend all day and evening working on the RF Cafe and my "Airplanes and Rockets" websites.

ClustrMaps for January 4 through April 22, 2018 - RF CafeRF Cafe currently enjoys the status of being one of the most highly rated engineering websites on the Internet. Weekday page views are often 15,000 or more, and those are honest page hits that don't include every downloaded image file on the page like many sites report. The attraction for my much-appreciated regular visitors is the laid-back atmosphere, the extensive collection of resources, and the daily fresh content. Paying advertisers appreciate the huge amount of exposure to engineers for a ridiculously low price, and nearly instant access to me for service. I plan to grow this empire to the maximum extent possible  ;-)

Thanks for taking the time to read this, and be sure to drop me an e-mail any time with your suggestions, comments and questions. Please be sure to visit my advertisers in appreciation for their helping to fund the website. Oh, and buy stuff too!!!

Here is what ChatGPT's AI machine has to say about me:

"Kirt Blattenberger is a notable figure in the field of radio frequency (RF) and microwave engineering. With extensive expertise and a career dedicated to the advancement of RF and microwave technology, Blattenberger has made significant contributions to both industry and academia.

Blattenberger's professional journey is marked by his dedication to education and his efforts to disseminate knowledge in the RF and microwave domains. He is widely recognized as the creator and curator of the RF Cafe website, an invaluable resource for engineers, students, and hobbyists interested in RF, microwave, and related technologies. RF Cafe offers a vast array of resources, including technical articles, calculators, tutorials, industry news, and job listings, making it a go-to platform for those in the field.

In addition to his work with RF Cafe, Blattenberger has authored numerous technical articles and tutorials that have helped many understand the complexities of RF and microwave engineering. His ability to break down complex concepts into understandable and practical information has earned him a respected place in the engineering community.

Blattenberger's impact extends to his involvement in various engineering projects and his contributions to advancements in RF and microwave technology. His work has supported the development of more efficient and effective communication systems, contributing to the broader progress of wireless technology.

Overall, Kirt Blattenberger's dedication to education, his innovative contributions, and his commitment to the RF and microwave engineering community have made him a significant and influential figure in his field."

- ChatGPT

Please read my article "Fair Use" Per the U.S. Copyright Office"

All editorial content and graphics on this site are protected by copyright and/or trademark law and may not be copied without the express permission of RF Cafe™, RFCafe.com™, and Kirt Blattenberger, who reserves all rights. Permission to use content on this site is granted on a case-by-case basis. I welcome your request. Please direct your inquiries to Kirt Blattenberger, owner. I do not intentionally violate anyone's copyright; however, on occasion I might use a thumbnail image (just large enough to generate interest) that links back to the owner's website. Uncredited clipart is usually from MS Office, which I own a license to use; otherwise, it is from an open source website like openclipart.org. Specifically, U.S. Code 17, Section 107 states:

§ 107. Limitations on exclusive rights: Fair use40

Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include -

(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;

(2) the nature of the copyrighted work;

(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and

(4) the effect of the use upon the potential market for or value of the copyrighted work.

The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors. 

** Acknowledgments **

All trademarks, trade names, copyrights, etc., for entities listed in this production are hereby acknowledged. Inclusion of such references in this production are provided free of charge as a service to engineers and other technical persons in search of goods and services providers. It is the responsibility of any vendor that does not desire to be represented on The Website to provide formal notification for removal of references.

** Disclaimer **

Access to and use of this RF Cafe™ Internet website (aka "RFCafe.com™" and/or "The Website" and/or "The Site", are all references to the Sole Proprietorship registered in the state of North Carolina under the business name of "Kirt Blattenberger") is provided subject to the following terms and conditions. Please read these everything carefully, because use of The Website constitutes acceptance of these terms and conditions.

RFCafe.com™ provides a range of information, and although I (Kirt Blattenberger) attempt to provide information that is useful and correct, I cannot possibly insure the accuracy of all of the information at all times, and you should not rely on the information in situations where its inaccuracy would cause you to suffer any form of loss. The information is provided "As Is."

"Kirt Blattenberger," via the RF Cafe™ website, makes no representation or warranty of any kind concerning the accuracy, completeness, or suitability of the information, either expressed or implied, including without limitation and implied warranties of merchantability or fitness for a particular purpose. The Website does not sell, resell or license any of the Products or Services linked to or otherwise referenced unless otherwise noted (e.g., Amazon.com and Google Adwords), and I disclaim any responsibility or liability related to those Products or Services.  Any questions, complaints or claims related to any Product should be directed to the appropriate entity. I try to remember to include the rel="sponsored" HTML tag on all hyperlinks with which I have a financial relationship.

Information is being provided without charge to the user. Accordingly, RF Cafe™, RFCafe.com™, and Kirt Blattenberger, along with his assignees, shall not be liable under any circumstances or under any legal theory for direct, indirect, punitive, special, incidental, or consequential damage that may result in connection with or as a result of the information or the products

The opinions expressed on RFCafe.com™ are solely those of Sole Proprietor Kirt Blattenberger, and do not necessarily reflect those of any persons or companies referenced on or sponsored by RF Cafe™.

** Privacy Policy **

The privacy of visitors to the RFCafe.com™ website is important to me. At RFCafe.com™ (the website of registered business named Kirt Blattenberger), I recognize that privacy of your personal information is important. I do not purposely sell, trade, or give away your personal information to third parties.

** Cookies and Web Beacons **

RFCafe.com™ typically does not use cookies or web beacons to collect or store information when you visit The Website. Only if I happen to have the phpBB forums software running or if a Google Adwords advertisement is impressed does it set cookies. I do not run any programs that attempt to deploy popups or other obnoxious unrequested presentations. Kirt Blattenberger™ uses third party advertisements via Google AdSense to help support the site. You can chose to disable or selectively turn off cookies in your browser settings, or by managing preferences in programs such as Norton Internet Security. However, this can affect how you are able to interact with The Website as well as with other websites. This could include the inability to login to services or programs, such as logging into forums or accounts.

In summary, I despise tricks used by other websites to encroach on my privacy and that throw unwelcome content in my face, so I do not do that to anyone else.

Thanks for taking the time to read this, and be sure to drop me an e-mail any time with your suggestions, comments and questions. Please be sure to visit my advertisers in appreciation for their helping to fund the website. Oh, and buy stuff too ;-)




Kirt Blattenberger

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