RF Cafe Software
About RF Cafe
1996 - 2022
BSEE - KB3UON
RF Cafe 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 ...
All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.
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These items are an archive of past Topical Smorgasbord items that have appeared on the RF Cafe homepage. In keeping with the "cafe" genre, these tidbits of information are truly a smorgasbord of topics. They all pertain to topics that are related to the general engineering and science theme of RF Cafe. Note: There is also a huge collection of my 'Factoids' (aka 'Kirt's Cogitations') that might interest you as well.
Forbes' 2011 List
of World's Billionaires
Forbes just published their annual list of the world's
billionaires (1,140 of them). It has not changed much at the top. Here are the high tech winners. Mexico's telecom magnate Carlos
Slim remains king of the hill with $74B, while Bill Gates plays second fiddle. Warren Buffet takes slot #3. #5 is Oracle's Larry Ellison. Googles
wonderboys share #24. Amazon's Jeff Bezos is #30. India's Wipro software guy Azim Premji sits at #36. Michael Dell: #46; Steve Ballmer: #38.
Facebook's Mark Zuckerberg ranks #52, but soon he might drop to sharing somewhere around #150 if a lawsuit by alleged co-founder
is successful. Malaysia's telecom giant Ananda Krishnan owns slot #93. The Wal-Mart Waltons occupy #10, 20, 21, and 22, 323, 409
(importing everything from China is good business). Un-PC Alert: Bill and Warren have given away a lot of their wealth the last
couple years, which affected their rankings. Maybe Mr. Slim should offer some of his wealth to fellow countrymen to return from their illegal
residences in the U.S., then let us see how he fares.
2010-11 Best Colleges
for Big Paychecks
America's 25 Fastest-
Growing Tech Companies
Need Not Apply?
recently, I believed that given the extended depressed condition of the job market that employers were sympathetic to the plight of its innocent
victims (not all are innocent). Surely a hiring manager or human resources staffer would not shun an otherwise qualified candidate
simply because he has not had any luck in securing a new position within a few months of having been laid off. That is probably the way you
see it too, right? Wrong. As it turns out, there is no mercy being shown. According to articles widely available on business websites and magazines,
the prevailing attitude is that this is an employer's dream scenario because the market is flush with highly qualified prospects (read
stories here, here, here,
here). This is not new; it happened as recently as the late 1980s / early 1990s. The
difference this time is that employers now are able to exploit people's willingness to expose everything about their personal lives on social
media websites like Facebook to vet for risky traits. Even without being "friended" there are ways to dig into posted content for revealing
facts about you. That has had a huge impact on many of the unemployed's attempts to find new work. The situation is so dire that there are now
services like Socioclean available for helping to assimilate all the locatable references
to you on the Internet and help scrub the party animal or radical activist reputation you have been so erstwhile proud of.
I have often said that some of the most capable and enthusiastic engineers and technicians - and even managers - I have worked with in my 30-something year electronics career have been amateur radio operators. They are the rare few who are able to combine a hobby passion with a profession that pays for the hobby... kind of like the airline pilot who flies model airplanes or the druggie who works at a pharmacy. Oh, wait, scratch that last example.
Here we see a video from Chevrolet where two engineers, one of them a Ham, took up the challenge to replace the AM/FM whip antenna originally planned for the 2011 Camaro convertible with a blended, inconspicuous antenna. Leaked photos of the prototype car showed the whip, which caused Camaro aficionados to descend upon Chevy requesting its removal. The flexible, folding rear window prevented an embedded solution as is the norm for many cars. The ultimate solution? Embed the antenna in the spoiler. <more>
Competition - Prizes!
Each year student technical paper and design contests are held as part of the MTT-S show. This year's
categories include a Student Paper
Competition, Student Design Competitions,
and new this year a Graduate Student Challenge.
Eight separate circuit design areas are available for selection -
and Innovative Modeling
Techniques. Winning any of these competitions would be a shining star on anyone's resume.
Applied Wave Research (AWR) will be sweetening the deal by giving
away fully-functional, one-year, personal-use licenses for Microwave
Office and Visual System Simulator to the top
3 winners / winning teams of the High-Efficiency Power Amplifier and
Wideband Balun competitions.
The value of each package will be worth as much as $10kUS... a nice bonus on top of gaining celebrity status!
Say Goodbye to America's
Space Shuttle Endeavour (named after the ship of British Lt. James Cook) lifts off for the last time tomorrow (April 29). Atlantis flies next month, marking the end of the USA's manned space flight vehicle program for the foreseeable future. Henceforth, we will be hitching rides on Chinese and Russian craft that still land in the desert using parachutes.
Here are some stats on the Shuttle program.
Number of shuttles: 5 - Challenger, Discovery, Atlantis, Endeavour; expected launches: 500; actual: 135; total flight time (as of Jan 2011): 1289 days; shuttles lost: 2 (Challenger, Columbia); total passengers: 836; failure rate: 1:67.5; fuel consumption rate: 660,000 lbs/min solid, 45,000 gpm liquid hydrogen; 17,000 gpm LOX; time to orbit: 8.5 min.; orbital speed: 17, 500 mph; touchdown speed: 220 mph.
As with our oil drilling industry, politicians have chosen to trash our domestic space transportation industry and send that money to countries that yearn for our demise. We pass on cutting edge technology, lend money (which rarely gets repaid), and even pay for the privilege <more>4/28/2011
One Heck of An Issue
For ten years I have been scanning all the major engineering magazines each month for content that I think
will particularly benefit RF Cafe visitors. You see links to those articles frequently in the homepage Recent Additions list, plus they are
archived for later reference. While looking through
the February 2011 edition of MicroWaves & RF (anyone notice the new title style?) two things greatly impressed me. First, nearly
every article is worthy of linking to because of the relevance to everyday circuit and systems designers. Second, many RF Cafe advertisers
have large ads for your edification. That goes for both MicroWaves &
RF and the Defense Electronics magazine insert.
An interview with Analog Devices' Barrie Gilbert (of Gilbert
cell fame), articles on Cellular Trends,
Understanding Dynamic Range,
Prevent PCB Problems in ISM-Band Designs, and
VCSO Technology Silences Synthesizers are among the many
that will keep you in rapt technical bliss. That doesn't even include the plethora of great Defense Electronics articles. Don't be
selfish -pass your copy on to a fellow engineer... or at least leave it in Wally's "other" office.
A Cornucopia of SecretsWhen I heard about the helicopter that went down during the raid at the bin Laden compound, my first concern after the safety of the crew was that now a high technology aircraft would be available to the enemy for inspection. Even after learning that the craft was "blown in place," I was still worried that unless some high temperature incendiary material like white phosphorous was used prior to the explosion, the pieces remaining would be in-tack enough to glean useful info. My worst fears were confirmed with the release of photos by Reuters (always sure to post images that could harm the U.S.) showing not just this large section of the tail boom and rotor, but also smiling kids walking around with scrounged parts of airframe and electronics gear. As an engineer who spent many years tearing down other company's designs to figure out how they designed and implemented leading edge circuits (and also checking for patent infringements), I can tell you that a circuit or system does not have to be in full functioning order to yield critical information. Material samples are now available for the stealth skin composition, lamination and attachment methods, and facet angles. Super quite airfoil and blade shape data is <more>
UK's Best UFO Hoax
by Engineering Students
Do you ever find yourself using a common
word or saying, and then suddenly realizing that you have no idea of its meaning or origin, even though you have used it often? Then, you ask
if anyone else knows the etymology and all you get is deer-in-the-headlights stares. Try this one in the lab later today: How did the AWG (American
Wire Gauge) system decide on wire sizes, and why are smaller wire sizes given larger numbers? Brown & Sharpe, a metrology tool company founded in the mid 1800s, standardized wire diameters. They decreed that No.
36 wire would have a diameter of 0.0050 inches, and No. 0000 ("4-ought") is 0.4600 inches in diameter. That leaves 40 wire sizes, with a diameter
ratio between largest and smallest of 92. Therefore, the geometric formula that governs in-between wire sizes (in inches, for solid wire) is:
OK, so why do small wires have larger numbers? It is because smaller wire gauges need to be drawn through the forming die a larger number of times.