RF Cafe Software
About RF Cafe
1996 - 2016
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.
My Hobby Website:
Try Using SEARCH
to Find What You Need.
There are 1,000s of Pages Indexed on RF Cafe !
These images have been chosen for their uniqueness. Subject matter ranges from historic events, to really cool phenomena in science and engineering, to relevant place, to ingenious contraptions, to interesting products (which now has its own dedicated Featured Product category).
Cool Pic Archive Pages
operator really stepped in it - or is about to... at least that is what it looks like at first glance. It is
actually a curled-up tungsten nanoscale probe after hitting a hard surface. IEEE has a short slide show titled
"The Art of Failure" that includes this photo, a human face, black tulips, and a lot of other amazing images.
Once again the evidence of amazing creativity is apparent. Witness this candy iPhone circuit board. If you are looking for an idea for a unique gift to give to the techie that has everything, try making him something like this. If you are not artistically inclined, maybe Sarah will make you one for the proper degree of con$ideration.
High tech weaponry is now at the personal level. It ranges from deadly to just unavoidably annoying. In today's PC theaters of operation, avoiding collateral damage (aka "innocent" standers by - often being used as human shields by bad guys) is more important than the safety of soldiers. So, before launching a computerized projectile that can detonate at designated locations and spray death around corners and into fox holes, GI Joe first gives warning with long-range deafening acoustic devices or warms the perp's skin with a microwave blast. Here are 10 notables.
Army Communications Electronics Museum at Fort Monmouth, NJ, has a nice collection of vintage equipment dating
back to WWI. Pictured here is equipment used by Edwin Armstrong, who invented frequency modulation (FM). Many
types of vacuum tubes (valves, for those of you across the pond), radios, field phones, cryptography sets, and
other devices of yore grace the displays. They even have Hitler's train car radio (definitely not a manpack).
It was 50 years ago that the first laser was demonstrated at Bell Labs. Here is a brief photo history of the development, beginning with masers and ending with semiconductor lasers. Low-cost, high efficiency red, green, and blue semi lasers are highly desired by display makers for high definition large screen TVs. Red came first by using GaAs compounds and then blue by using GaN. Green has been not so easy. Achieving the holy grail of 520 nm, where true "green" begins, was achieved just last year - hard to believe, huh?. Read all about it in IEEE's Spectrum.
Occasionally, a full moon coincides with the point in its elliptical orbit that is its closest - or nearly so - approach to Earth (called the perigee). January 29th was one of those times, resulting in the largest, brightest full moon of 2010. It was roughly 14% greater in diameter and 30% brighter than will be any of the rest of the year's full moons. Absolutely clear skies and an outside temp of 6 °F produced this quite cool photo taken through my back patio door (from the inside where it was 70 °F).
not sure how common wire-wrapping is for electronics prototyping anymore. Having spent the last 20 years
working with mostly analog circuits in the RF realm and being very sensitive to low level signals, the only
thing I borrowed from the W-W realm was Kynar insulated 30 GA wire for making jumpers on a PCB. Back in the
mid-late 1980s while working as a technician at Westinghouse, I did a lot of wire-wrapping of digital circuit
cards for MIL-SPEC sonar systems. It was a real pain routing, leaving a proper service loop, and assuring that
the correct number of turns were accomplished. The results of the effort made for a picture worth framing.
Imagine if the standard physical meter bar in France was stored in a room where a coffee machine was set next to it after 100 years of being alone. Suddenly, metrologists began to notice that the meter was seemingly getting longer. Alarmists began screaming that the Earth was getting smaller, portending certain doom as it would surely fracture and crumble. Former high-ranking politicians and preferred group leaders became multi-millionaires by exploiting the lack of applied rigor in the scientific method. Entire economies were upset because anyone questioning the veracity of measurements of exalted scientists was impugned as a "hater of science." Nah, it could never happen.
Texting on your phone while driving has become a real problem. 19 states bans texting while driving, and many more are have legislation pending. Often, laws are initiated as the result of a high profile accident involving death. Two years ago my 18-year-old niece, who lived in Maryland, was texting while driving at night, lost control of her car, crossed a wide median strip, and slammed into a tractor trailer. She died in a totally flattened car. The lady driving the rig was unharmed, thanks to her significantly more massive vehicle, but the incident could have killed innocent people... and "I'm sorry," does not bring back lives.
picture has been making the rounds on the Internet the last few days. It shows exhausted Microsoft employees
in China sleeping at their work stations where they assembly MS Mouse products. Working 15-hour shifts at
34p/hr (52¢/hr), the 10-minute breaks are spent sleeping. Of course people love to
hate MS, but lots of other companies have been shown to use slave-like labor. China does not consider it abuse
since, after all, citizens have free health care. As documented by
BehindTheLabel.com, your stylish Ambercrombie & Finch or Banana Republic clothing was likely made made in
a sweatshop. Do a search on "slave labor" + company name.
If you thought that making a phone call from your car is a recent manifestation of technology, think again. This photo from the Library of Congress collection of technical images (c.1958) shows a fair lady feigning use of a experimental model of the new "drive-in" telephone developed by Bell Telephone Laboratories. The concept must not have taken off. Of course, the good thing about this scheme is that no moron ever killed or maimed anyone while talking. What model car is that?
Here is a really slick downloadable poster (full-size) created for National Geographic magazine. It is a condensation of all the extra-Earth space missions in the last 50 years - both manned and unmanned. With the Space Shuttle program shutting down this year (the last mission was the final night launch), with no guarantee of a new vehicle for manned missions. Not to worry, though, NASA will rent space on Russian and Chinese rockets on a space-available basis. Be sure that our technology will be transferred to them along the way... another stake through the heart of America. Communists rejoice.