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:
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
I think back at the engineering labs from my days in school, I wonder how much things have really changed from then
until now. It is hard to believe that freshman and sophomore labs are not still consumed with radial lead resistors,
inductors, and capacitors, solderless breadboards, and a variety of light bulbs, motors, transformers, relays, and
rheostats. By the time you move into the junior year, labs have gotten a bit more intense with microprocessor controls
(mine used an 8088 CPU with machine language programming for the serial port), some high voltage apparati[sic],
digital logic circuits (74-series leaded ICs), and a chance to lay out/fabricate/populate a PCB. On-hand test equipment
consisted of 2nd or 3rd generation o-scopes, signal generators, and power supplies. I did a search for photos of
labs from back in the early to mid 1900s to see if much had changed from then until the time I was in college. Here
are a few of the pics that I found. If you appear in any of these pictures, you are really old.
Google is famous for its homepage logo honoring significant dates in history. In fact, that is where I got the idea many years ago to do the same thing for RF Cafe. Today's logo looks like it could be a belated tribute to Halloween, but in fact it is a commemoration of Wilhelm Roentgen's November 8, 1895, discovery of x-rays during an experiment ("x" stood for "unknown" cause). Many scientists and doctors eventually suffered gruesome effects from x-ray exposure during early years, losing appendages, organs, and even suffering death from the strange new rays. Amazingly, some willingly sacrificed themselves for the sake of advancing the knowledge even after such dangers were known. Look here if the Google logo is gone from their site.
The old adage about having to learn to walk before you can run applies to just about everything - including nanoscale structures. Here, nanoarchitects assembled colored strands of the DNA double helix into a Möbius strip. Doing so is a demonstration of the ability to manipulate nanostructures at a near atomic level. It is a great publicity stunt to help garner interest and support for the technology. Colorfully stained DNA is the pièce de résistance. The world of nanomedicine is advancing as rapidly as nanoelectronics and nanomechanics. Don't forget, when the day arrives, I have already claimed the copyright to zeptoeverything. My heirs will be pleasantly surprised.
that "most wonderful time of the year" again, as the Burl Ives song goes (remember from
the Rudolph cartoon?). With it comes the growing assortment of over-done Christmas light displays. Using
as much electricity in one month as their owners' homes normally consume in the other eleven months, these displays
are probably visible from habitants of the International Space Station. Some are gaudy, but many are an impressive
work of art. The neighborhood where I live here in Erie, PA, is full of young families with kids, and the houses
and lawns are chock full of lights and those inflated displays of Santa, manger scenes, Snoopy, the Grinch, and
snowmen. I remember standing outside on a cold, calm night, and hearing what sounded like a motor running . A while
later I heard another from a different direction. Then, I realized it was the air pumps that keep the displays inflated.
Old Ebenezer might consider it noise and light pollution, but I love it - especially with snow falling and laying
all over the place!
Most of us in the electronics world have used at least one instrument made by the company that Joseph F. Keithley founded in Cleveland, OH, back in 1946. One photo in the group of the office shows auto fan belts hanging on the walls, a pot belly stove, and an old phone like Sherriff Taylor used to speak to Sarah. Keithley's first product was the Phantom Repeater, also seen in the office on the table, which amplified low-level electric signals. The device was used by physicists, chemists, and engineers. With continual growth over the decades, Keithley built a new corporate headquarters and manufacturing facility in Solon, OH, in 1967. Keithley routinely spends more than 10% of its global revenues on R&D.
They went public on the NYSE on Nov 29, 1995, the founders got rich, and they lived happily ever after ;-).
Stop. Don't throw out or donate that old cell phone. Thanks to the creativity of an unknown innovator, there is a better use for it - a phone wallet. Maybe the genius of creation is that it makes a great place to hide your money so that thieves will overlook it while robbing you. Oh, wait, thugs like to steal cell phones as much or more than they like to steal wallets. Oh well, maybe it's time to go back to the old drawing board. The Recyclart website has a host of other wonderful recycling ideas as well - like bicycle wheel sidewalk borders, a light bulb terrarium (using an evil Edison incandescent), and a shed made of car hoods. Is the NEA funding this stuff? The library info desk built from books is very clever, I have to admit. Be inspired.
Allen, of Microsoft fame, has donated a lot of his ample cash cache to pushing back the frontiers of ignorance in
the science realm. Allen is a major player
in the commercial space travel effort and has joined with genius aerospace engineer
Burt Rutan and his Scaled Composites company
that won the Ansari X-Prize. He also funds numerous science
museums and research projects, including SETI's, well, search for extraterrestrial intelligence. Since there is
no telling on what wavelength a possible ET might be broadcasting, it is necessary to "listen" over a very wide
bandwidth. So, SETI's Allen Telescope Array,
made possible by Mr. Allen, uses a set of 42, 6.1-meter dishes that employ an extended cross-polarized log-periodic
antenna covering 500 MHz to 11 GHz. Its >20:1 ratio is the
widest in existence. After 50 years, no Alpha Centaurians or Procyonites have bothered to call, or else they
have not emitted a loud enough
Yip or Yopp for us to hear.
Sure, we're all tired of hearing about the TSA privacy abuses, but if we shut up about it, the situation will just get worse. After all, that's how we got to the point of full-body scanners and government-approved strangers touching our "junk." TSA claims that radiation levels are about the same as 2 minutes of flying on the plane. The mm-wave units are not the focus of safety concerns because they emit a less potent kind of radiation. Rapiscan System's "backscatter" scanners emit X-ray-like ionizing radiation that in larger doses can cause cell changes leading to cancer, but it is the revealing images that are the outrage. Keep in mind who is responsible for this as you read stories about our record-breaking arms sales deal to Saudi Arabia, the home country of 15 of the 9/11 hijackers. Here is a current list of airports with the scanners.
Aside from being an amazing photo, this panoramic shot of Dresden, Germany has the unique distinction of being the largest pixel-count image in the world (as of December 2009). The picture was made with the Canon 5D mark II and a 400mm-lens. It consists of 1.665 full format pictures with 21.4 megapixel, which was recorded by a photo-robot in 172 minutes. The converting of 102 GB raw data by a computer with a main memory cache of 48 GB and 16 processors took 94 hours. It has a resolution of 297,500 x 87,500 pixel (26 gigapixel). In the background you can identify outlines of the Saxon Switzerland. Use your mouse to zoom and pan around the image for incredible detail.
university researchers and industry could create micromachined or even chemically etched structures like this, fortunes
could be made. Self-assembling nanobots have managed to arrange themselves into tubes and rods, but the exquisite
complexity of facet orientation and symmetry displayed in these x-rays images of common snowflakes are for now the
domain of nature alone. Scientists study the molecular intricacies and electric forces that create such complex
and, supposedly, unique 3-dimensional forms by the googlillions (my word) all
around the world, every day, without a single machine or computer program. To the utter embarrassment of members
of the Church of Global Warming, these beauties have recently appeared in
during the summer.
Even by 1958, telephone service was still somewhat of a novelty for many people; only 76% of U.S. households had telephones. The 7-digit, All Number Calling (ANC) system was instituted to handle the burgeoning amount of private phone lines being installed. Touch-Tone service was still a couple years away. Bell Telephone Company of Pennsylvania regularly published a magazine called, "The Telephone News," primarily for employees, but also as a public relations medium. Most of the Christmas edition is used for showing employee activities involving decorating offices, gift swapping, and, of course, lots of festive goodies to eat. It also includes service award, safety tips, and reports on installation and maintenance projects. One obvious departure from today's official public company publications was the phone company's use of the word Christmas, rather than Holiday throughout.
As Steampunk is to things mechanical, so is Electronpunk (my word) to things electronic. Thankfully, there are a lot of people out there who make a hobby of constructing circuits that perform contemporary functions using vintage components. Recall the Nixie tube watches, the restoration projects, technical museums, and plethora of available components for building and repairing vintage equipment. Shown here is the front panel of Bill Buzbee's handcrafted Web server as it might have been built in the late 1960s and early '70s. More than 200, 74-series TTL ICs are spread across 5 wire-wrap prototype cards. Around 4,000 wire-wrap lines are used. Bill estimates it has the computing power of an i8086 μP. Building the five cards took about four months worth of evenings and weekends.