See Page 1 |
2 |
3 |
4 | of the February 2023 homepage
archives. Tuesday the 14th
 As is usually the case, in this "Recognizing
the Profession" installment of Mac's Service Shop, valuable lessons on business
practices and/or technical know-how are presented along with an interesting storyline.
In the early 1960's when appearing in Electronics World magazine, vacuum tube radios
with point-to-point interconnections were standard fare. Components like capacitors,
potentiometers, tuning coils, wire insulation, and even dial cord were vulnerable
to moisture under normal operating environments, but were particularly prone to
significant damage when immersed in salt water. Mac brought a relative's radio
home with him from a Florida vacation in hopes of resurrecting it after a dunking.
Carbon tetrachloride (aka "carbon tet") was used as a cleaner and to displace
as much of the water as possible - a widely recognized method of treatment under
the circumstances. Even in the 1960's, carbon tet was known to be a potentially
grave threat to health, so Mac makes a point here to describe proper use of it.
Today, you might rather use WD40 for the job, given that the "WD" part of the name
stands for "water displacement"...
 "Restoring power quickly after a
major blackout
can mean the difference between life and death, but cold starting an entire electrical
grid is a complex and delicate process. A hybrid computer model from Sandia National
Laboratories that combines optimization, physical simulations, and cognitive models
of grid operators promises to come up with a fast and reliable plan to get the lights
back on. While power outages are always disruptive, they typically impact only smaller
portions of the overall grid. A complete loss of power over the entire network is
much more serious, and requires operators to effectively jump-start the grid with
so-called 'black start' generators. This involves a complicated balancing act to
avoid mismatches between energy generation and consumption, as different sections
of the grid are gradually brought back online. Get it wrong and the grid can collapse
again..."
 Here is a batch of
electronics-themed comics that appeared in the January 1949 edition of Radio &
Television News. The scene seen (hey, homonyms) on the page 118 comic was commonplace
in the 1940s when televisions were relatively new and not every household had a
set. The scenario repeated itself in the 1960s when color sets were hitting the
consumer market. I remember people standing outside the display window at Rickey's
TV & Electronics store in Parole Plaza, Annapolis, Maryland. Now, people can
watch TV on their smartphones while not at home so gathering 'round the television
display in a store is relegated pretty much to little kids watching the Disney movies
that seem to always running on them. There is an ever-growing list of other comics
at the bottom of the page...
 Here we go again. Another significant landmark
of U.S. achievement is on the chopping block. Despite the
Sugar Scoop Antenna at Bell Labs enabling one of the most significant discoveries
in the field of astrophysics - the cosmic microwave background (CMB) - and it being
designated as a National Historic Landmark, its future is in peril. Per this "Saving the Big Bang
(Antenna)" article on the IEEE Spectrum magazine website, the antenna itself
could be removed and stored somewhere else. This is what is happening to many historic
sites and artifacts once foreign entities with no connection to America's past buy
companies, real estate, and other entities from the original U.S. owners. In this
case it is where current Nokia
Bell Labs sold the site to Indian entrepreneur and chemical engineer
Rakesh Antala. After reading the
article please sign this petition to preserve the
Sugar Scoop
Antenna site.
 Folded dipole antennas, as the name suggests,
are about half the length of a regular dipole, and work just as well for many applications.
I have had one attached to my FM radio receiver for many years and it does a great
job pulling in stations from as far away as Toronto, Canada, and Detroit, Michigan
(from Erie, PA). Receiver sensitivity and oscillator stability has been able to
obviate the need in most cases for super performance antennas in modern receivers,
as evidenced by ear bud wires and even conformal patch antennas in smartphones sufficing
in lieu of a "real" antenna. It is a real tribute to the brilliance of engineers
that cellphones work so well on multiple bands that accommodate frequencies ranging
from 88 MHz (FM), through 900 MHz (GSM), 1.5 GHz (GPS), 2 GHz
(UMTS), and WiFi (2.4 GHz) - all in one compact device with no external antenna...
 New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 16,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. 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.
 Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today - and don't miss the blog articles!
Monday the 13th
 This "Microwaves
for the Beginner" article from a 1969 issue of Popular Electronics
magazine is still a good primer on how to build circuit boards which operate in
the gigahertz frequency realm - in this case 2,300 to 2,450 MHz, which falls
within today's popular 2.4-2.5 GHz ISM band. Grain-of-salt size components
were not available back then, so some techniques common in the day are used to fabricate
small value inductors and capacitors needed for efficient operation. The transistor
used is a KMC part number H104. I had a really difficult time discovering who KMC
was, but finally found a reference to them in a patent and in a CAGE Code list used
by the U.S. government. KMC Semiconductor Corporation was located in Long Valley,
New Jersey. A couple instances of the KMC H104 transistor show up in "73" magazine,
and interestingly, in one circuit it is drawn as a PNP rather than an NPN. The antennas
for both the transmitter and receiver are dipoles mounted against a plated PCB ground
plane...
 TotalTemp Technologies has more than 40
years of combined experience providing thermal platforms.
Thermal Platforms
are available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating & circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
 "'All things are numbers,' avowed Pythagoras.
Today, 25 centuries later, algebra and mathematics are everywhere in our lives,
whether we see them or not. The Cambrian-like explosion of artificial intelligence
(AI) brought numbers even closer to us all, since technological evolution allows
for parallel processing of a vast amounts of operations. Progressively, operations
between scalars (numbers) were parallelized into operations between vectors and,
subsequently, matrices. Multiplication between matrices now trends as the most time-
and energy- demanding operation of contemporary AI computational systems. A technique
called "tiled
matrix multiplication" (TMM) helps to speed computation by decomposing matrix
operations into smaller tiles to be computed by the same system in consecutive time
slots. But modern electronic AI engines, employing transistors, are approaching
their intrinsic limits and can hardly compute at clock frequencies higher than ~2
GHz..."
 In 1819, Hans Christian Øersted, a Danish
scientist, made one of the most important single discoveries in the field of electricity.
While experimenting he accidentally brought a small compass near a wire carrying
an electric current and noted that the needle no longer assumed its usual north-south
direction, but aligned itself at right angles to the wire. By this observation he
had discovered the principle of electromagnetism-namely, that a magnetic field always
surrounds a conductor carrying a current. While he probably didn't realize its importance,
Oersted had discovered the key to the vast fields of commercial electricity. whenever
a current flows, a magnetic field always exists around it. If the conductor in which
the current flows is a straight wire, the field takes the form of concentric circles
or rings of magnetic force around the wire. You can check this experimentally with
a small pocket compass. Since a compass needle always aligns itself parallel to
magnetic lines of force, the needle also will be at right angles to a current-carrying
conductor. You can perform this experiment with dry cell, a piece of wire...
 Direct signal sampling at the antenna has
been the goal of receiver designers since the early days of digital radio. Doing
so eliminates the noise added by the transmission line, and simplifies circuitry
by eliminating mixers, filters, amplifiers, etc. Steady progress has been made toward
the goal, and
direct sampling receivers have been around for many years - limited by the operational
frequency of the integrated circuit semiconductor technology. Here is a good synopsis
of the state of the art, on the Microwaves & RF website (9-minute
video). "Mercury Systems' Ken Hermanny and Rodger Hosking discuss the company's
deployment of Direct RF technology in its signal-processing products for defense
and aerospace applications. While it's not a brand-spanking-new technology, Direct
RF receiver architectures are now coming to the fore in numerous aerospace and defense
applications, such as radar and electronic warfare. Direct RF architectures bring
a host of advantages. For one, they eliminate the need for a mixer or local oscillator
for frequency downconversion...."
 Here is the Radio Service Data Sheet for
the
Canadian Westinghouse Model 175, 7-Tube Dual-Range Superhet as it appeared in
the May 1936 edition of Radio-Craft magazine. This is in tabletop format and has
a Bakelite cabinet rather than the more common wood. Using a moldable material permitted
a more stylish (in some people's opinion), curvaceous shape with a high shine. Radios
with Bakelite cabinets that have been kept in a climate controlled, protected environment
still look almost new even nearly a century later (see example from the RadioAttic
website). With six vacuum tubes in the receiver circuit (the seventh is the power
supply rectifier), this radio likely has very good selectivity and audio quality.
I post this schematic and functional description manufacturers' publications for
the benefit of hobbyists and archivists who might be searching for such information
either in a effort to restore a radio to working condition...
 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...
 Centric RF is a company offering from stock
various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power
levels from 0.5-500 watts are available off the shelf. Order today, ship today!
Centric RF is currently looking for vendors to partner with them. Please visit Centric
RF today.
Sunday the 12th
 This custom RF Cafe
electronics-themed crossword puzzle for February 12th contains words and clues
which pertain strictly to the subjects of electronics, mechanics, power distribution,
engineering, science, physics, astronomy, chemistry, etc. If you do see names of
people or places, they are directly related to the aforementioned areas of study.
As always, you will find no references to numbnut movie stars or fashion designers.
Need more crossword RF Cafe puzzles? A list at the bottom of the page links to hundreds
of them dating back to the year 2000. Enjoy.
 It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
 Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets
exceedingly high standards of quality, performance and excellent value, and are
100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz.
Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production.
All products are custom designed. We will find a solution and save your time and
cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters. In stock,
1-day free shipping.
Friday the 10th
 As did/do most technically-oriented magazines,
Radio-Electronics ran a monthly news of the day column that contained short
blurbs on recent happenings - inventions, research, personnel promotions, industry
events, etc. The December 1968 issue was loaded with plenty of good tidbits. One
notable is Raytheon's amazing new "Tel-O-Riginator"
(aka telephone-originator) for an early example of Amazon same-day service that
would Make the entire country 5 hours wide and 3 hours deep." It doesn't mention
whether a drone could deliver the goods. The audiophile contingent was no doubt
tantalized at the appearance of an eighth-sphere surface array of speakers. The
USSR's space timetable was supposed to be far ahead of U.S. efforts. Jack Binns,
who famously transmitted the first wireless SOS signal - from the SMS Titanic no
less - had recently passed on. Mr. Binns also wrote the foreword to many of
The Radio Boys story books. Read on for more breathtaking happenings...
Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets
exceedingly high standards of quality, performance and excellent value, and are
100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz.
Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production.
All products are custom designed. We will find a solution and save your time and
cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters. In stock,
1-day free shipping.
 Most people engaged in circuit design and
adjustment in a professional environment own or have access to a spectrum analyzer
and/or digital oscilloscope with an FFT function, so measuring the harmonic content
of a signal is a fairly simple job. A lot of instruments will display a listing
of frequency makeup and the percentage of the whole signal it occupies. Many, though,
particularly hobbyists, use simple analog o-scopes where determining harmonic content
requires a largely subjective assessment of the displayed waveform. In 1939 when
this article appeared in QST magazine, almost nobody, whether amateur or
professional, had even an analog spectrum analyzer available, and therefore relied
on drawings and a trained eye to discern
harmonic content. The original article included two sets of full-size drawings
of the distorted waveforms - one for comparing to a 2-inch CRT display and another
for a 3-inch CRT. The user could trace the shapes onto a piece of onion paper and
overlay...
 "White LEDs' reign as the top light source
may soon come to an end with the advent of a new alternative that offers superior
directionality. A photonic crystal or
nanoantenna, a 2D structure with periodic arrangement of nano-sized particles,
is being developed as a cutting-edge optical control technology. Upon exposure to
light, combining a nanoantenna with a phosphor plate produces a harmonious mix of
blue and yellow light. White LEDs have already been improved upon in the form of
white laser diodes, or LDs, which consist of yellow phosphors and blue LDs. While
the blue LDs are highly directional, the yellow phosphors radiate in all directions,
resulting in an undesired mixing of colors. To address this issue, researchers have
developed phosphor plates combined with nanoantennas using metallic aluminum, enabling
increased photoluminescence..."
 Here is
Bendix Models 636A, C, D schematic and parts list as featured in a 1947 edition
of Radio News magazine. No operational or alignment information was provided. The
636A is a tabletop radio using five vacuum tubes in the detector and amplifier stages,
and a single vacuum tube rectifier in the power supply. Its shiny Bakelite cabinet
sported an Art Deco style, which was popular back in the day. The images to the
left are from a recent eBay listing, for $60, where the seller says it is in working
condition. As mentioned many times in the past, I post these online for the benefit
of hobbyists looking for information to assist in repairing or restoring vintage
communication equipment...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 16,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. 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.
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude 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!
Thursday the 9th
 Amrad,
American Radio & Research Corporation,was based in Medford Hillside, Massachusetts
and was founded in 1915 with funds from J. Pierpont Morgan. The company's first
manager, Harold James Power, was an amateur radio enthusiast and built a research
laboratory. In 1916, Amrad made its first broadcast to J. Pierpont Morgan Jr., who
was aboard the ocean liner "Philadelphia." Amrad received orders for military radio
equipment during World War I, but discontinued these orders after the war ended.
To keep the company afloat, Amrad produced items such as electric egg beaters and
cigar lighters. In 1919, Amrad was awarded a contract to make 400 SE1420 receivers,
and it began advertising components for amateur radio enthusiasts. Amrad's crystal
set was a popular product and helped the company during difficult times...
 A PCB stack-up is a high-level outline created
before laying out the printed circuit board. Regardless of size, ensuring a good
stack-up definition can greatly improve long-term reliability and performance, reduce
production costs, and allow for a smoother transition to manufacturing. San Francisco
Circuits has put together a
PCB Stack-Up Guide. This new resource includes all relevant stack-up details
that should be included and provides examples for MCPCBs, HDIPCBs, RF PCBs, Flex
PCBs, and Rigid-Flex PCB stack-ups. Other stack-up requirements that are covered
include PCB lamination methods, board type & application, board component density,
component types & interfaces, and mechanical requirements...
 $15.1 billion was a lot of money back in
1963 when this story was published in Electronics World magazine. It was
the
value of the electronics market at the time. $15.1 billion is still a lot of
loot today, but according to the Bureau of Labor Statistics' Inflation Calculator
it is now the equivalent of $147 billion. The Consumer Electronics Association projects
a 2015 electronics gadget market value of $223B, which does not include military,
medical, and industrial electronics. The World Semiconductor Trade Statistics group
predicts a $333B semi market value for 2014. Apple alone just hit the $700B market
cap benchmark - that's just one electronics company. By any measure, electronics
has enjoyed a continual, significant gain since the early 20th century...
 Why go to the trouble and expense when you
can get away with floating a cheap
balloon over all North America? "In the sky over southwest China, a team of
researchers has been testing a new wing design that they said could help unmanned
aircraft better
evade radar. The drone, which has no tail, appears to be a scaled-down version
of the United States Air Force's B2 Spirit bomber, and can fly without the use of
elevators, ailerons or flaps - the hinged moving parts known as elevons that help
control flight direction - according to the researchers. 'Our work is a first,'
the team from the China Aerodynamics Research and Development Centre in Sichuan
province said in a paper published on January 19 in the peer-reviewed journal Acta
Aeronautica et Astronautica Sinica..."
 Here is a brief but informative introduction
to the story behind French physicist
Andre Marie Ampere's discovery of the eponymously named law that governs the
relationships between current flow and a magnetic field. It appeared in a 1972 issue
of Popular Electronics magazine. As most RF Cafe visitors know, both a
steady state and time-varying current will generate a magnetic field, but only a
time-varying magnetic field can generate a current flow. In less than a week after
witnessing Hans Christian Ørsted's demonstration of a current-carrying wire influencing
a compass needle, Ampere discovered the Right-Hand Rule of current flow direction
based on the direction of the magnetic field...
 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...
 Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector
Network Analyzers include an RF measurement module and a software application
which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware
via USB interface. The result is a lower cost, faster, more effective test process
that fits into the modern workspace in lab, production, field and secure testing
environments. 50 Ω and 75 Ω models are available, along with
a full line of precision calibration and connector adaptors.
Wednesday the 8th
 When this "Four
New Sources of Power" article appeared in Radio-Electronics magazine
in 1960, most people had never heard of a fuel cell, the Seebeck effect, thermionic
effects, or magnetohydrodynamics. All had been around as features embedded in common
products in some manner, like thermionics in vacuum tubes. It is pointed out that
Sir Humphrey Davy invented the fuel cell technique in 1802, thermoelectricity by
Thomas Seebeck in 1821, thermionic effects by Thomas Edison in 1878, and magnetohydrodynamics
by Michael Faraday in 1831. Today, all four types of power sources have been integrated
into a host of products. Whereas thermionics was among the most common in 1960,
it might be the least common of the four nowadays...
 This
Bulova Accuquartz wristwatch is not the first quartz-controlled wearable timepiece;
however, it was the first to be manufactured in the U.S. Interestingly, it is not
a fully electronic watch because the quartz crystal stimulates a mechanical tuning
fork which ultimately drives the hands. Bulova's first tuning-fork-driven "Accutron"
was introduced in 1960. It sported a 360 Hz tuning fork that was stimulated
by a pair of electromagnets. The story appeared in a 1972 issue of Popular Electronics
magazine. The retail price at the time (pun intended) was $395, which in 2023 money
is equivalent to $2,832 (per the BLS Inflation Calculator)! I found a couple nice
photos of the Accuquartz...
 "'This partnership will build on SPL's
world-first 5G demonstration from the stratosphere in 2022,' said SPL CEO Richard
Deakin. Funded by Innovate UK, the trials will be at BT's labs at Adastral Park
and 'could offer transformational opportunities for sectors operating in remote
areas such as transport, maritime security and search and rescue,' said BT.
Stratospheric Platform's
(SPL's) antennas are designed to communicate directly with standard 3G, LTE/4G,
5G phones. The eventual aim is to create a 20 kW >3 m diameter version
for flight, with 500 individually steerable beams, each intended to be equivalent
to a cell created by traditional terrestrial masts - delivering up to 150 Mbit/s,
and covering a 140 km diameter, or 15,000 km2 land area. 'Virtually
any shape of beam coverage can be painted on the ground,' according to SPL..."
 There are still many old-timers and beginning
nostalgic collectors out there who nurse heirloom and otherwise procured vacuum
tube radios - like this
Arvin Models 150TC, 151TC combination radio / phonograph - back to health (operating
condition) and/or keep them in good health. While it is possible to purchase schematics,
parts lists, and service instructions from many different models, there are still
some that have escaped the scanners of those publishers. For those kindred spirits
in search of such reference materials, I happily scan, clean up as necessary, and
post this collection (see complete list at bottom of page). I have dozens more that
will eventually be added over time, so check back later or send me an e-mail if
I have an issue (check the lists first, please) of Radio News, Radio-Craft,
etc. known to contain the information you need...
RF Cascade Workbook is the next phase in the evolution of
RF Cafe's long-running series, RF Cascade Workbook. Chances are you have
never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system
cascade parameter and frequency planner that includes filters and mixers for a mere
$45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch
and the format is entirely customizable. It is significantly easier and faster than
using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
 Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners (hence "Triad") with
over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
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.
Homepage Archive Pages
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
|
