See Page 1 |
2 |
3 |
4 | of the February 2024 homepage archives.
Wednesday the 7th
We take a lot of conveniences for granted
these days. They are so commonplace that we don't even consider that the features
have not always been available. Your age, of course, plays a part in it. For instance,
a Gen Z person might be shocked to learn that at the time he was born a cellphone
only performed the function of a telephone. A Millennial might assume the air bags
and anti-lock brakes on car she drives have been there since Henry Ford shipped
his first Model T (Henry who? Model what?) and shuddered to think about not
having a personal computer and dial-up Internet connection. Gen Xers figured
cable TV and MTV had always been how entertainment was delivered, and that a Walkman
was the transistorized version of those vacuum tube devices their parents used to
carry while jogging. Baby Boomers, of which I am a member, actually used electric
drills which had merely an on/off switch, with no variable speed. Having been born
in 1958, I was only seven years old when
Skil Power Tools came out with what is pitched in this 1965 issue of Popular
Mechanics magazine as the world's first variable speed power drill. My father, who
was not a big power tool guy (he had mainly a hand saw for cutting wood and metal,
a brace and bit for drilling holes, a block of wood with sandpaper stapled to it
for sanding, and a good set of lungs for an air compressor when something needed
to be blown off. He also had one of those mechanical screwdrivers with the spiral
groves in the shank.
![Ferristor? - RF Cafe](../../../references/radio-news/images5/ferristor-keep_small.jpg)
This
Ferristor was discovered by RF Cafe visitor Russell G., in the UK. His
friend, a vintage American car owner, gave it to him, wondering if it was related
to his 1950s vintage Buick Roadmaster. It bears the markings "Ferristor," "TLX-1,"
and "On <-> Off." An extensive search using multiple engines does not turn
up any identification. It appears to have a red and white / blue LED, so that dates
it no earlier than the 1970s - 1990s. At first glance it looks like a mini flashlight,
but there's no bulb. If you know what this is, please send me an e-mail...
Biographies abound focusing individually
on Albert Einstein, Thomas Edison, Isaac Newton, Alexander Graham Bell, and Henry
Ford. Someone, somewhere, is right now researching and writing yet another dissertation
on each of them and other well-known historical figures of science and engineering.
Guys like
Michael Faraday rarely have books dedicated solely to their lives and accomplishments,
even though it is not unreasonable to expect that they would. Faraday, Alessandro
Volta, Georg Ohm, André-Marie Ampère, Anders Celsius, Max Planck, et al, are usually
included in books featuring a collection of people who have achieved notoriety in
similar fields. Accordingly, most of us know little, if anything, about their upbringings
or what led to their claims to fame. Here from a 1973 issue of Popular Electronics
magazine is a brief insight into just those aspects of the man whose namesake is
the root of units of capacitance and identifies a common type of shield (aka "cage")
used to isolate devices from external electromagnetic fields...
"The
chip war between China and the United States now extends beyond the Earth and
into space. According to scientists directly involved in China's extraterrestrial
chip program, China's Tiangong space station can now test more than 100 computer
processors simultaneously. More than 20 new high-performance chips spanning the
28- to 16-nanometre process range have already passed testing. They are considerably
more advanced than chips used by other countries in space. NASA has said the chips
it currently uses in space are based on 30-year-old technology. For example, the
RAD750 processor used in the James Webb Space Telescope, the most powerful space
telescope ever that was launched in 2021, was manufactured using antiquated 250-nanometre
technology and has a clock frequency of only 118 MHz - less than a fraction of that
of a typical smartphone chip. The scientists said the chips tested on Tiangong were
designed and manufactured entirely within China. During testing they were run on
China's independently developed SpaceOS operating system, which is widely used on
China's space station and other space facilities. It is expected that more domestic
chip makers will soon be queuing up to put their top-tier offerings through the
rigors of space testing, the team led by Liu Hongjin, of the China Academy of Space
Technology, wrote in a peer-reviewed paper published in the Chinese academic journal
Spacecraft Environment Engineering in December..."
Hallicrafters was founded in Chicago in
1932 by William J. Halligan. He formed the company name based on a combination of
Halli(gan) and (hand)crafters - clever, non? Since Hallicrafters made radio gear
for commercial, amateur radio, and military applications, their advertisements appeared
in most of the major electronics magazines of the time - QST, Popular
Electronics, Radio & Television News, etc. It is interesting to
see how product physical appearances changes over the years as user preference,
materials, and technologies evolve. Knobs, dials, and toggles switches have been
largely replaced by pushbuttons nowadays. This full-page ad appeared in the February,
1970 issue of Popular Electronics...
ConductRF is continually innovating and
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and phased matched VNA applications as well as standard & precision RF connectors.
Over 1,000 solutions for low PIM in-building to choose from in the iBwave component
library. They also provide custom coax solutions for applications where some standard
just won't do. A partnership with Newark assures fast, reliable access. Please visit
ConductRF today to see
how they can help your project!
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 280,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the
place to be...
Tuesday the 6th
Prior to the availability of Internet news
websites, magazines were one of the primary sources for learning of recent happenings
in science, engineering, mechanics, medicine, and other technical subjects. Newspapers
carried stories put out by sources like the Associated Press (AP) and United Press
International (UPI), but unless something world-changing happened, the reports were
usually buried deep inside the pages where almost nobody saw it. Publications like
Popular Science, Popular Mechanics, Mechanix Illustrated,
Science and Mechanics, etc., were one of the best sources for a wide range
of subjects. Most of them dedicated a few pages each month to sections like this
"Science Worldwide" collection of newsworthy items in a 1965 issue of Popular
Mechanics. At that time, the island of Bermuda had finally been accurately
located thanks to being able to observe the positions of Echo I and Echo II
satellites in orbit against a background of fixed stars (we'll they're not really
fixed, but traverse the sky in apparent position via "proper motion"). No doubt
GPS positioning has more precisely located Bermuda since then. Note the "The meteorological
climate" item...
For some reason I was recently contemplating
pi (π).
Pi has been an enigma in the realm of mathematics and physics since it was first
recognized as being irrational. The fact that the ratio of a circle's circumference
to its diameter is an inexact number has caused enormous amounts of consternation
for dogged investigators of the aforementioned phenomenon. Pythagoras is believed
to have first noticed the irrationality of certain numerical ratios when even something
as basic as the corner-to-corner diagonal of a unit square could not be calculated
to a finite precision. In some religious circles (see what I did there?) even contemplating such thoughts
caused souls to be burned at the stake for daring to assert that such an imperfection
could exist in a perfectly created world. Recall that Galileo was excommunicated
for asserting that the earth was not the center of the universe. I kid you not.
For anyone not familiar with irrational numbers, they are numbers with non-zero
decimal places that do not end and do not have a repeating sequence. The "do not
end" part is what bothers me about pi. Consider that we normally measure rotation
in angular units of radians, and that 2π radians is defined as one full rotation.
If we never had to count more than a single rotation, then stopping at something
other than an inexact number is not so bothersome... although it actually is bothersome
since the rotation stops exactly at some angle even if it cannot be measured in
terms of pi. It doesn't asymptotically approach a exactly quarter of a turn at but
never actually stops. Rotation can stop at exactly a quarter turn (exactly 90°)
even if π/2 radians itself is inexact. Rotation can stop at exactly half a turn
(exactly 180°) even if π radians itself is inexact. That just doesn't seem right...
February 13, 1935, was probably the first
case of a major news organization incorrectly reporting a courtroom verdict because
of a
radio communications fail - the birth of Fake News! The Associated Press (AP)
thought it was being uniquely creative - and sneaky - during "The Trial of the Century"
involving the kidnapping and murder of Charles Lindberg's young son. A reporter
secreted in a miniature shortwave transmitter, concealed within a leather brief
case. A receiver station above the courtroom stood ready to copy the agreed upon
code, based on the verdict, and send the results to its newspaper feeds. Little
did they know that a competing news agency had the same idea, but used a different
code. The AP operator received the New York Daily News code assuming it was from
the AP mole. It immediately sent the incorrect story to hundreds of editors across
the world. An account of the failed scheme appeared in the June 1935 issue of
Short Wave Craft magazine...
"Delivered by Dstl and the DragonFire partners
- MBDA, Leonardo and QinetiQ - the trial builds on the first
static high-power laser firing of a sovereign UK capability and demonstration
of the DragonFire system's ability to track moving air and sea targets with very
high accuracy at long range. In a statement ,Chris Allam, managing director, MBDA
UK, said: 'Together, the DragonFire partners and Dstl are demonstrating exceptional
UK capability in laser directed energy weapons. The DragonFire system has been successfully
proven to date and we are now closer than ever to having a unique weapon that will
enable frontline commands to meet the rapidly changing threats they face.' The DragonFire
weapon system is the result of a £100m joint investment by industry and the UK Ministry
of Defence, and together the companies involved are supporting UK jobs in new pioneering
technologies that are delivering a significant step-change in the UK's capability
in LDEW systems..."
Since new people are constantly entering
the field of electronics, there is a constant need to post articles covering some
of the basics of the craft. Just as the seasoned practitioner looks to currently
published magazines and books for guidance, so too do contemporary technician and
engineer fledglings. Decibels have long been a cause of confusion for many - even
some who have been in the field for many years. I have seen on many occasions engineers
who are way smarter than me routinely mix units of dB (dimensionless) with units
of dBm and dBV (power and volts, respectively) when writing. In this 1974 Popular
Electronics magazine piece entitled "Understanding
Decibels," author George Board does as good of a job as anyone I've read at
explaining the basics...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks (EIA
19", ETSI 21"), and more. Test equipment and racks are built at a 1:1 scale so that
measurements can be made directly using Visio built-in dimensioning objects. Page
templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
Monday the 5th
When this infomercial from Radio Corporation
of America (RCA) describing the effects of sun spots and their associated solar
flares appeared in a 1948 issue of Popular Science magazine, the science of coronal
mass ejections (CME) had not yet been established. That began in 1971 with the first
visual detection by the Orbiting Solar Observatory 7 satellite. The difference between
a solar flare and a CME is basically one of magnitude. Flares are typically visually
bright and send out energetic particles at near the speed of light, and reach Earth
in a matter of a few minutes. A CMEs is an enormous spewing of solar mass (primarily
a plasma of electrons and protons); its particles can take between half a day and
many days to get here. The Carrington Event of 1859 is one of most significant CMEs
documented (before anyone knew about CME). Both interact with the upper atmosphere,
but a CME can generate extreme electrical and magnetic fields that interrupt RF
communications and can disrupt electrical distribution grids. A common comparison
is that a solar flare is like a muzzle flash whereas a coronal mass ejection is
like the leaden projectile...
This article from a 1970 issue of Popular
Electronics magazine is a timely mate to the monthly list of career-related
resources recently posted since it discusses jobs in electronics not necessarily
at the degreed engineer level. Along with both diploma and certificate programs
by local colleges,
home study courses in electronics have been around since the early part of the
last century. Cleveland Institute of Electronics began offering courses by mail
in 1934, and has been running advertisements in trade and technology magazines for
as long as I can remember. It was in business until 2022 - probably a victim of
the COVID scamdemic. Nowadays, many home study courses - many that offer certificates
- are available online...
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post that covers the
functions of Spectrum and Network analyzers to better understand which type
of test equipment is better suited to support your project requirements. Instrumentation-level
analyzers come in many shapes and sizes, including as signal, spectrum, and network
analyzers. Knowing what each analyzer does will help find the best one for the job.
Spectrum analyzers measure signal magnitude as a function of frequency. They detect
known signals, such as radio waves, and unknown signals, such as interference and
noise. Spectrum analyzers work with antennas for over-the-air (OTA) measurements
of wireless communications signals and radar pulses. While signal and spectrum analyzers
offer extensive measurement results on OTA signals, they lack the capabilities of
network analyzers (NAs) for studying the effects of electronic networks on signals...
Here is another tech-themed comic from a
1973 issue of Popular Electronics magazine. There are usually two or more
per edition, but not this time. It took looking a second time to figure out what
the guy in the comic was referring to - pretty funny after I "got it." There is
a hyperlinked list at the bottom of the page for the hundreds of comics I've posted
over the years. It's a shame that comics rarely appear in contemporary technical
magazines...
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4,000,000 pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 280,000
per year (in eight locations on each page, with >17,000 pages). That's pretty
good exposure for $300 per month. Some companies have expressed an interest in being
able to manage their advertising accounts themselves a la the Google AdSense program...
Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products such as
RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters.
Since the conception of WFT, we have introduced products that have been purchased
by a wide range of customers, from hobbyists to education facilities to government
agencies. Worldwide customers include Europe, Australia, and Asia. Please contact
Windfreak today to learn how they might help you with your current project.
Sunday the 4th
This custom RF Cafe
electronics-themed
crossword puzzle for February 4th contains only clues and terms associated with
engineering, science, physical, astronomy, mathematics, chemistry, etc., which I
have built up over more than two decades. Being the 4th day, words containing the
letter "D" are marked with an asterisk (*). Many new words and company names have
been added that had not even been added to the world's technical lexicon when I
started in the year 2002. As always, this crossword contains no names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless
it/he/she is related to this puzzle's technology theme. You might, however, encounter
the name of a movie star like Hedy Lamarr or a geographical location like Tunguska,
Russia, for reasons which, if you don't already know, might surprise you. The technically
inclined cruciverbalists amongst us will appreciate the effort. A full list of all
RF Cafe crosswords is at the page bottom. Enjoy!
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers"
Smith chart design. These would make excellent gifts for husbands, wives, kids,
significant others, and for handing out at company events or as rewards for excellent
service. My graphic has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. I only make a couple bucks
on each sale - the rest goes to Cafe Press. It's a great way to help support RF
Cafe. Thanks...
Friday the 2nd
When the United Nations (UN) was created
at the end of World War II, the goal was for a consortium of countries that
would band together to resolve disagreements without armed conflict both within
member nations and with non-members - a noble cause. This 1948 issue of Popular
Science magazine reported on
amateur radio operators contributing to the effort. It did a good job for the
first couple decades, then over time, as with too many such efforts, corruption
crept into the ranks from top to bottom and reports began appearing of barbarous
acts being committed by UN commanders and troops (yes, they were militant) in areas
of Africa and the Middle East. An Internet search on UN atrocities turns up many
example (some censor/block the articles), the most recent being UN staff participation
in the October 7th terrorist attack on Israel. Once a supporter of the United Nations'
mission, I used to collect the special postage stamps they issue, and even have
First Day Covers of the original 1951 set, but stopped years ago due to not wanting
to help fund their actions. The UN is nowadays one of the most anti-American organizations
in the world...
Signaling with light goes back to ancient
times when militaries and towns communicated with simple encryption methods. Paul
Revere relied on lamp light signals (i.e., one if by land, two if by sea). Sailors
use(d) signal lamps relay simple messages. Even the Warning Beacons of Gondor were
a form of
light beam communications (albeit 1 bit -- lit or not lit). To date, the farthest
distance over which reliable (at useful data rates) terrestrial communications has
been accomplished on a light beam is about 2 miles. Atmospheric contamination
and Earth curvature (line-of-sight with a tiny bit of refraction assistance) are
the primary limiting factors. By contrast, millions of miles have separated successful
space communications, but the baud rates are typically measured in the hundreds
or thousands of bytes per second. This 1972 article from Popular Electronics
magazine reports on experiments being carried out with lasers. Their terabit data
rate predictions are being realized today...
""MIT researchers have developed an additive
manufacturing technique that can print rapidly with liquid metal, producing large-scale
parts such as table legs and chair frames in a matter of minutes. Their technique,
called
liquid metal printing (LMP), involves depositing molten aluminum along a predefined
path into a bed of tiny glass beads. The aluminum quickly hardens into a 3D structure.
The researchers say LMP is at least 10 times faster than a comparable metal additive
manufacturing process, and the procedure to heat and melt the metal is more efficient
than some other methods. The technique does sacrifice resolution for speed and scale.
While it can print components that are larger than those typically made with slower
additive techniques, and at a lower cost, it cannot achieve high resolutions. For
instance, parts produced with LMP would be suitable for some applications in architecture,
construction, and industrial design, where components of larger structures often
don't require extremely fine details. It could also be utilized effectively for
rapid prototyping with recycled or scrap metal. In a recent study, the researchers
demonstrated the procedure by printing aluminum frames..."
There was no shortage in the 1970s of articles
recommending how to choose and install the perfect television antenna. People would
swear by the advice given. This piece by Mr. Harvey Swearer is a good example.
Of the four manufacturers with pictured antennas - Gavin, Channel Master, Lance,
and Jerrold - only Channel Master still exists today. Lance Industries made the
ColorMaster TV antennas, and appears to have been out of business since around
2003. Gavin Electronics seems to be gone as well. I found an ad for the Gavin #1118
antenna (like the one in this article) in a 1973 Pennsylvania newspaper for $24.99.
Interestingly (to me, anyway), the ad was run by Boscov's department store, which
is the company that just moved into the former Sears, Roebuck store here in the
mall in Erie, PA (they don't sell antennas anymore). Jerrold Electronics is also
long gone. The above ad came from a 1974 edition of a Connecticut newspaper. RF
Cafe visitor Bob D., an Iowa native, sent a note reminding that Iowa-based
Winegard still manufactures old fashioned multi-element, multi-band television antennas.
It began as Wells-Winegard in 1952...
With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols
available for RF, analog, and digital system and schematic drawings! Every object
has been built to fit proportionally on the provided A-, B- and C-size drawing page
templates (or can use your own). Symbols are provided for equipment racks and test
equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous
versions, these are NOT Stencils, but instead are all contained on tabbed pages
within a single Visio document. That puts everything in front of you in its full
glory. Just copy and paste what you need on your drawing. The file format is XML
so everything plays nicely with Visio 2013 and later...
Thursday the 1st
Last summer while at a community feast I
was talking to a guy who recently moved from California - tired of the craziness
there. He could be from the cast of Duck Dynasty, and has a strong independent spirit.
He described a water pumping system he was considering installing which was self-powered
and could lift the water from his pond up to a storage tank about 10 feet off the
ground. There is no electrical power for running a pump near the pond. His herd
of a couple dozen cows and a handful of sheep and pigs would be the beneficiaries.
In my ignorance, I was thinking, dude, how do you expect water to pump itself up
to a higher level; that violates conservation of energy. Fortunately, I kept my
thoughts to myself. After reading this "Hydraulic
Ram Forces Water to Pump Itself" article in a 1948 issue of Popular Science
magazine, I realized it is exactly what he was describing! Commercially made hydraulic
ram pumps are available for <$100, or you can easily build you own using instructions
and videos on the Web. The downside is there is a lot of spilt water in the process.
Also, the effectiveness of the pump depends on how far below the source level the
pump is situated...
"Teledyne e2v HiRel announces the availability
of a
rad-tolerant UHF to S-band low noise amplifier, model TDLNA0430SEP that is ideal
for use in demanding high reliability space applications where low noise figure,
minimal power consumption and small package footprint are critical to mission success.
This new LNA is developed on a 90 nm enhancement-mode pseudomorphic High Electron
Mobility Transistor (pHEMT) process. It is available in an 8-pin dual-flat no-lead
(DFN) 2 mm x 2 mm x 0.75 mm plastic surface mount package and is
qualified per Teledyne's Space enhanced plastic flow. It is now available for immediate
shipment from our DoD Trusted Facility. The TDLNA0430SEP LNA leverages monolithic
microwave integrated circuit (MMIC) design techniques that deliver exceptional performance
for UHF to S-band communication channels. The amplifier delivers a gain of 21.5 dB
from 0.3 GHz to 3 GHz while maintaining a noise figure of less than 0.35 dB
and an output power (P1dB) of 18.5 dBm..."
A major transition in the realm of test
equipment readouts from analog to digital was occurring during the 1970s. Prior
to then, what few digital displays existed used Nixie tubes, but the emergence of
inexpensive LEDs, combined with equally inexpensive digital logic ICs, made the
change an easy decision. D'Arsonval meter movements are prone to damage when even
slightly overdriven or subject to physical impact. Analog meter movements still
have their place in a few applications (like when a quick at-a-glance, pert-near
reading is good enough, particularly with slow, continuous level changes), but the
precision and repeatability of digital circuitry, plus lack of subjective interpretation
of a pointer's position makes it the option of choice most of the time. This 1974
Popular Electronics magazine "How
to Make Custom Meters from Salvaged Parts" article might have been in a WWII
era script from when new electronics parts were hard to find since everything was
going toward the war effort. Unbeknownst...
Another great concept, but impractical from
a cost ($½ million) and implementation standpoint (see specs). Showing the EV as if for
charging is buffoonish. "On average, a humble wind turbine uses less land area per
megawatt-hour than almost any other power source. Even so, a wind turbine and its
tower can sometimes be too cumbersome. The still-nascent field of
airborne wind energy
(AWE) has a solution: Swap out the turbine for a kite on a string. Not only is a
kite nimbler than a turbine, it can deliver a more constant energy supply. The steady,
intense winds some 500 meters above sea level are capable of generating 1,800 terawatts:
enough to power the entire planet multiple times over. Even an entire flock of Kitepower's
Hawks will only tap the lightest touch of that potential power. One entrant trying
to put AWE to market is the appropriately named Kitepower. This year, the Netherlands-based
company will begin shipping its first system: the 40-kilowatt Hawk. Far from replacing
traditional turbines, Kitepower hopes the Hawk can power sites that might turn to
polluting diesel generators: temporary microgrids..."
What better way is there to begin another
week of long hours, marginally useful meetings, unpredictable customers, nagging
design and/or production issues, and, hopefully, even a success or two, than to
see a couple
electronics-themed comics from a mid-last-century magazine? These appeared in
1947 edition of Radio & Television News. Seeing a comic panel in any
modern technical magazine these days is rare, if for no other reason than a fear
amongst publishers (and their lawyers) that somebody, somewhere might be offended.
BTW, these comics make good fodder for the front page of your technical presentations
- a good way to soften the edge going into a meeting, especially if you are not
good at delivering jokes. Once again, I took the liberty of colorizing them...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers"
Smith chart design. These would make excellent gifts for husbands, wives, kids,
significant others, and for handing out at company events or as rewards for excellent
service. My graphic has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. I only make a couple bucks
on each sale - the rest goes to Cafe Press. It's a great way to help support RF
Cafe. Thanks...
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
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