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4 of the November
2022 homepage archives.
Monday the 14th
Survey of Transistor Development
Mr. B. N. Slade, of the Tube Department
of Radio Corporation of America, wrote a series of articles on
transistor development for three 1952 issues of Radio & Television News
magazine. Consider that it was only four years earlier, a few days before Christmas,
that Messrs. Bardeen, Brattain, and Shockley announced their game-changing invention
of the point contact transistor. Already a plethora of commercial transistors were
on the market for incorporation into new electronic products. At the time, germanium
was still the semiconductor of choice, although silicon was gaining ground in laboratories.
This article covers the three basic transistor circuit topologies of common emitter,
common base, and common collector, which are analogous to vacuum tube circuits using
common cathode, common grid, and common plate topologies, respectively. Operation
up to around 200 MHz was obtainable...
Thanks Again for Windfreak
Technologies' Continued Support!
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
NYC Residents Complain About "Ugly" LinkNYC 5G Poles
Yeah that's a serious issue. After all, would
you want one of those "ugly" poles being the last thing you see before getting
pushed in front of a subway train, getting
mugged in broad daylight, or OD'ing on a
fentanyl-laced pill? It seems to me NYC residents have a lot more to worry about
than how more free stuff is being provided to them. "The idea is to provide free
and equitable telecom and connectivity services, but
LinkNYC is getting dinged for aesthetics and the placement of 32-foot structures
around the streets of New York City. Some residents are calling them eyesores. Others
are worried about safety due to their placement. 'No one asked us about the design
or where they should go. We have notes,' said a Brooklyn neighborhood group on Facebook.
As The New York Times wrote last weekend, the 'towers' are part of LinkNYC efforts
to install about 2,000 Link5G poles over the next several years in an effort to
help eliminate the city's 'Internet deserts.'' A prior attempt to cover the city
with Wi-Fi connectivity didn’t come to pass..."
After 50 Years, Digital Voices Speak Again
Have you ever seen one of these? I haven't.
This type of flexible vinyl record used to be a popular way for magazines to incorporate
audio extras according to this IEEE Spectrum magazine article entitled,
50 Years, Digital Voices Speak Again." Says Stephen Cass: "'Ali Baba knew how
men buy lime.' 'The beach is dry and shallow at low tide.' 'Few thieves are never
sent to the judge.' These cryptic sentences - and more than a dozen like them -
were contained in a 1973 issue of IEEE Spectrum. But unless you happen to have a
perfectly preserved physical copy you would never know they existed. It is impossible
for any other reader to locate them, even using the IEEE Xplore digital library.
The reason for their ongoing absence is that they never actually appeared in print.
Instead, they were encoded in the grooves of a phonograph record bound inside the
magazine. And there they would have stayed without a chance conversation and assistance
from some very capable librarians and archivists." This
Eva-Tone Soundsheet entitled
"Sounds from Space" can be heard on YouTube (others, too)...
General Electric Model 219 Tabletop Radio
When searching the Internet for examples
General Electric models 219, 220, and 221 tabletop radios, all I could come
up with for the 219 is a picture from a Sam's Photofact sheet. A really nice GE
model 220 is now for sale on eBay (see screenshots below). The phenolic cabinets
were very nice, being a simulated wood grain pattern and color. A GE model 221 also
happens to be for sale right now. The November 1946 issue of Radio News
magazine had the schematic and parts list for the three radios, but no textual description.
To the left is a full-page ad from a 1946 issue of The Saturday Evening Post
magazine which included the GE model 220 tabletop radio. There are still many people
who restore and service these vintage radios, and often it can be difficult or impossible
to find schematics and/or tuning information...
RF & Electronics
Symbols for Visio
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...
Many Thanks to Reactel for Their
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
Sunday the 13th
Electronics Themed Crossword for November 13th
Here is your custom made
Electronics Themed crossword puzzle for November 13th, 2022. All RF Cafe crossword
puzzles are custom made by me, Kirt Blattenberger, and have only words and clues
related to electronics, electricity, radio, radar, RF, microwave, and mm-wave engineering,
optics, mathematics, chemistry, physics, and other technical subjects. 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 (e.g., Reginald Denny or the Tunguska event in Siberia).
The technically inclined cruciverbalists amongst us will appreciate the effort.
RF & Electronics
Stencils for Visio
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...
Many Thanks to Aegis Power Systems for
Their Continued Support!
Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
Friday the 11th
Mac's Electronics Service: Intermittent Roundup
Just about anyone who has done a fair amount
of troubleshooting on electrical and/or electronics equipment has experienced the
frustration (to put it mildly) of trying to identify the source of an intermittent
problem. As Mac points out in this "Mac's
Electronics Service: Intermittent Roundup" story from a 1962 issue of Electronics
World magazine, the causes can be electrical, mechanical, or thermal. A combination
of two or all three might even be cohorts in making your life miserable. If poor
power cord or battery connections are not the culprit, then I typically start exercising
switches and twisting knobs in search of any one of them causing an unexpected change
in the functionality. Following that, I'll open the device and sniff and look around
for obvious failures. Next comes unplugging and plugging back in all the internal
connectors (multiple iterations) in case a contact is contaminated. If no joy is
produced by that point, it's time to pull out the DMM and start checking easily
determined voltages from power supplies...
Please Visit Empower RF's Website in
Appreciation of Their Support
Empower RF Systems is the technological
leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat
Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers
incorporate the latest semiconductor and power combining technologies and with a
patented architecture we build the most sophisticated and flexible COTS system amplifiers
in the world. Solutions range from tens of watts to hundreds of kilowatts and includes
basic PA modules to scalable rack systems.
Nominate a Colleague for IEEE Major Award
Award" is up for grabs. Maybe this is the year RF Cafe finally gets recognition
for its decades of contributions. Any Major Award I might get would be akin to the
Leg Lamp in
A Christmas Story ;-) Says IEEE: "Each year IEEE pays tribute to
technical professionals whose outstanding contributions have made a lasting impact
on technology and the engineering profession for humanity. The IEEE Awards program
seeks nominations annually for IEEE's top awards—Medals, Recognitions, and Technical
Field Awards—that are given on behalf of the IEEE Board of Directors. You don’t
have to be an IEEE member to receive, nominate, or endorse someone for an award..."
Return of the Prodigal Ham
Here is another article about a
"prodigal" Ham who returned to amateur radio after about a 30-something year
respite, per this 1955 Popular Electronics magazine. Author Charles Meistroff's
previous experience had been with surplus World War I - yes that's WWI! He must
have been in Heaven to be able to now get his hands on all the new-fangled equipment
now (then) available on the World War II surplus equipment market! I don't know
if the military is still making surplus equipment available like they did even up
through Korea and Vietnam. There must be some great stuff from the Middle East wars
if it is circulating within the surplus market. Then again, other than ruggedness
factors, most commercial equipment is as good or better than MIL-SPEC stuff...
Salary & Career Survey: Continuing Education
Microwaves & RF magazine just
released the results of their
2022 Salary & Career Report: Continuing Education. It is one category of
the overall survey. This pathetic statement (not MRF's fault) begins the
report, "Our survey indicates that fear of contracting disease is no longer the
big barrier to continuing education that it was in 2020 and part of last year."
It is yet another reminder of the misanthropic COVID scam perpetrated upon the entire
world by a relative handful of powerful bureaucrats and politicians... but I digress.
The main takeaways are that lack of time the most limiting factor in continuing
education. Work-life imbalance rates up there, too, compounded by long commutes.
Company support (or lack thereof) is a limiting consideration; 27% said they get
no form of reimbursement of time off for continuing education...
Western Electric, 1945 Saturday Evening Post
Here is an advertisement by
Western Electric from the August 25, 1945, edition of the Saturday Evening
Post magazine. As with many of the advertisements of the era, this ad refers
to the company's contribution to the war effort during WWII. "How communications
help tighten the ring," accompanies a map of the Japanese islands. All forms of
battlefield and shipboard communications benefitted from the innovations of Western
Electric scientists, engineers, and assembly line workers. These days Western Electric
manufactures special purpose audio frequency vacuum tubes and amplifiers to use
them. They're not cheap. Back in 1945, Western Electric was a major manufacturer
of telephone and telegraph equipment for Bell Telephone, Western Union, and America
Telephone & Telegraph (AT&T). Dr. Lee de Forest, inventor
of the Audion amplifier tube, worked for Western Union...
Veterans Day 2022: A Pittance of
This is my annual
Day tribute. On November 11 (the 11th day of the 11th month), at 11:00 am (the
11th hour), we observe two minutes of silence in honor of countrymen who "gave the last full measure of devotion." A Pittance of Time
is performed by Canadian citizen Terry Kelly (he
went blind at an early age). It was written after an experience he had on Veterans
Day in 1999. It is done in the finest Celtic tradition.
RF Cascade Workbook
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...
Many Thanks to Berkeley Nucleonics
for Continued Support!
Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
Thursday the 10th
Carl & Jerry: Dog Teaches Boy
In his usual manner, John T. Frye uses
this "Dog Teaches Boy" episode of
Carl & Jerry technodrama story to present a lesson in electronics. A method
for cooking hotdogs using the standard 117-volt household supply was used to admonish
the reader regarding necessary conditions for electrocution. Maybe it's from being
so familiar with working around electricity for many decades, but the comment about
some people believing that 117 volts can't kill you seems incredible. I do have
to take exception to the claim that switching the neutral wire along with the "hot"
wire is a safer way of doing things. The National Electric Code prohibits doing
so except under certain very specific conditions. The reason is because the neutral,
being connected to the same point electrically as the ground in the circuit breaker
panel, should always be connected so that any current present has a low impedance
path. Most people have no idea how electrical systems work, and I have known people
who believed that you can only get shocked from the hot wire. The fact is...
Please Thank IPP for Their
Innovative Power Products (IPP) has over
35 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband
couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools available,
resulting in unrivaled product performance. Applications in military, medical, industrial
and commercial markets are serviced around the world. Products listed on website
link to detailed mechanical drawings that contain electrical specifications as well
as performance data. Please take a couple minutes to visit their website and see
how IPP can help you today.
Chart of Radio Symbols
Chart of Radio Symbols would make a nice wall poster for your office, lab, or
Ham shack. It has a nice vintage look to it - because having been scanned from a
1935 edition of Radio-Craft magazine, it is a true vintage relic. Although it would
look great in its gray scale format, importing it into a graphics program and adding
a little color would really jazz it up. A bit of brown would provide an aged sepia
look, or you could go all out and custom color each square (I created one for you).
Click on the image to have the high resolution version display for printing...
Braiding Enables Antenna Fabrication for Next-Gen Devices
"Antennae that work at frequencies needed
for next generation phones and wireless devices can be fabricated with a machine
developed in the U.S. These devices will require antennae that work at tens of gigahertz
but making them will require
braided filaments of about one micrometer in diameter. Now a team of researchers
from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS)
has developed a simple machine that uses the surface tension of water to grab and
manipulate microscopic objects, offering a potentially powerful tool for nanoscopic
manufacturing. The research is published in Nature. 'Our work offers a potentially
inexpensive way to manufacture microstructured and possibly nanostructured materials..."
Anatech Intros 3 Filter Models for
Anatech Electronics offers the industry's
largest portfolio of high-performance standard and
customized RF and microwave filters and filter-related products for military,
commercial, aerospace and defense, and industrial applications up to 40 GHz.
Three new filter models have been introduced - an 849 MHz cavity bandpass
filter with a 5 MHz bandwidth, a DC-1440 MHz / 2200-2500 MHz LC diplexer,
and a 20 MHz LC highpass filter with a 1.5 dB insertion loss. Custom RF power
filter and directional couplers designs can be designed and produced with required
connector types when a standard cannot be found, or the requirements are such that
a custom approach is necessary...
High-Q Tank Circuit for Ultra-High Frequencies
When I see that mechanical drawing of an
oscillator tank circuit, the cross-section of a screw-on type automotive oil
filter comes to mind. Ham radio operators who build their own equipment have never
shied away from tackling leading-edge, technically challenging projects. Indeed,
many Amateurs have pioneered radio circuit, antenna, and propagation concepts that
were later adopted by military and commercial concerns. One of the first examples
was the relegation of hitherto believed to be unimportant shortwave frequency bands
for amateur radio use. Quite unexpectedly, Hams quickly took up the challenge and
exploited the unique long range communications capabilities possible due to atmospheric
channeling and reflection phenomena. This 1939 QST magazine article features
coaxial resonant cavities used to construct high-Q oscillators. While the title
says "Ultra-High Frequencies," the highest frequency mentioned is for 1¼ meters,
that is around 240 MHz, which according to today's spectrum assignments doesn't
quite reach into the 300 MHz to 3 GHz realm...
Promote Your Company on RF Cafe
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 12,000 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. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
Many Thanks to Amplifier Solutions
Corporation (ASC) for Continuing Support!
ASC designs and manufactures hybrid, surface
mount flange, open carrier and connectorized amplifiers for low, medium and high
power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon
(Si) transistor technologies. ASC's thick film designs operate in the frequency
range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up
to 20 GHz.
Wednesday the 9th
The Counter as a Test Instrument
A few years ago I was in a second-hand shop
in Erie, Pennsylvania, and happened to spot a Hewlett−Packard model HP 5212A Electronic
Counter stashed in a cardboard box with a bunch of other electronic stuff. It was
a little dirty, but otherwise appeared to be in pretty good condition. I took it
to the counter and asked the lady what she'd take for it, and we agreed on $15,
provided when I plugged it in the front panel display would light up and no smoke
came from the chassis. It did and it didn't, respectively. Once at home, I fired
it up and ran some functional tests on it, and all seemed to be working properly.
After performing some major clean-up to nearly like-new condition, I decided it
should go to someone who could put it to good use, so it went up for sale here on
RF Cafe. Believe it or not, the best offer received was $125. It deserved more respect
than that, but the guy was a collector of vintage test equipment, so at least it
went to a loving home. This 1962 "The
Counter as a Test Instrument" article in Electronics World magazine article
shows both the HP 5212A (300 kHz) and the HP 5243L (500 MHz)
Artemis Moon Rocket Launch Set for November 14th
All the world's astronauts have been launched
to the ISS via the communist, America-hating countries of Russia and China since
the Space Shuttle program shut down in
2011 (with no
standby replacement capability). "NASA's moon rocket
is back on the pad for another launch attempt, following more repairs. The 322-foot
rocket departed its hangar in the middle of the night and completed the 4-mile trip
shortly after sunrise Friday. NASA is aiming for a launch attempt on Nov. 14, sending
an empty crew capsule around the moon and back in a dramatic flight test before
astronauts climb aboard in a couple years. Forecasters are keeping their eyes on
potential tropical weather that could interfere. It is NASA's biggest step yet to
get astronauts back on the moon by 2025. The space agency is nearing the 50th anniversary
of its last human moon landing: Apollo 17 in December 1972..."
How to Make Power Transformer Substitutions
Power transformers have not changed too
much since this article was appeared in a 1959 issue of Popular Electronics magazine.
Efficiencies might be up a bit, and maybe sizes down, but other than that, the equations
and implementation methods are about the same. True, you will not find a lot of
new transformers with secondaries that sport vacuum tube filament and plate voltages,
but their equivalents for ±15, ±12, ±5, etc. are out there. 60 Hz transformers
are of course most common here in the U.S. (50 Hz in Europe), and 400 Hz
is a common frequency for military equipment (ships, aircraft, tanks, etc.), but
I was surprised to learn that 25−cycle (25 Hz) power was at one time common
near hydroelectric plants. Niagara Falls, in Buffalo, New York, was one of the first
to adopt 25 Hz, in part because of a belief that the AC motors used in nearby
industrial applications would be more reliable at lower commutator frequencies (see
"25-Hz at Niagara Falls - end of an era on the Niagara Frontier"). Other frequencies
such as 8-1/3 Hz, 16-2/3 Hz, 25 Hz, 33-1/3 Hz, and 41-2/3 Hz were proposed. As you
might expect, a lot of politics and corporate battling played into the final decision...
CETECOM Launches RF Automotive Experience
CETECOM, a global company providing automotive
test and certification services, announces the first-of-its-kind
Automotive Experience Lab (AEL). This innovative testing center, which opens
on November 1, 2022 in Silicon Valley, is designed as a proof-of-concept lab for
automotive application testing in a simulated environment. CETECOM, with more than
25 years experience in testing and certifying RF devices, leads the project, which
will enable automotive engineers to validate component-level hardware designs during
the HIL phase. With early access to cutting-edge test equipment, automotive application
teams can significantly reduce design time, saving development costs and getting
their product to market more quickly. CETECOM is offering one free four-hour session
in the lab, which includes a consultation with CETECOM experts and training...
High Tech Comics
A wee bit of levity in the form of comics
is good for the soul on a busy workday.
Good humor, it is said, contains a degree of truth in it, and this group from
vintage editions of Radio-Craft magazine is no exception. One of the comics
in particular struck a chord with me - the one with the table model radio where
the serviceman is speaking on the phone with his customer. The first familiar feature
is the shape of the radio and the removed rear cover; it reminds me of my Tesslor
R-601S. The second thing is the dead bugs. Just like a stray cat will climb into
your car's engine compartment on a bitter cold day in search of heat, so will bugs
be drawn to a heat source such as that provided by an electronic appliance filled
with warm, glowing vacuum tubes - they might have liked the brightness as well.
I remember well removing the backs of radios and TVs to find carcasses of bug colonies
scattered around the electronics chassis. A couple years ago I bought a Snoopy and
Woodstock telephone from the 1960s to restore. Although it was not a heat generator,
the components were covered with tiny spots of bug excreta both on the outside and
on the inside...
Post Your Engineer & Technician
Job Openings on RF Cafe for Free
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
Many Thanks to Exodus
Advanced Communications for Their Support
Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Power amplifiers ranging
from 10 kHz to 51 GHz with various output power levels and noise figure
ranges, we fully support custom designs and manufacturing requirements for both
small and large volume levels. decades of combined experience in the RF field for
numerous applications including military jamming, communications, radar, EMI/EMC
and various commercial projects with all designing and manufacturing of our HPA,
MPA, and LNA products in-house.
Tuesday the 8th
Auto−Sembly of Miniature Military Equipment
According to this "Auto−Sembly
of Miniature Military Equipment" article from a 1951 issue of Electronics
magazine, the U.S. Army Signal Corps first experimented with chemically photo−etched
printed circuit boards (PCBs) in 1949. Someone there got the idea from seeing the
way nameplate manufacturers created similar signs for doors, desks, equipment nomenclature
plates, etc. The authors wrote numerous articles* in numerous magazines over about
a five year period on the Auto−Sembly process whereby leaded components are inserted
into substrate through-holes, and then dipped into a solder bath as a complete assembly.
Some history on the research is provided regarding photoresist compounds, etching
mixtures, parameters of copper traces based on foil thickness and width (resistance,
current handling), and other critical items. RF impedance measurement are not discussed
since at the time only low frequency (DC, audio, and control signals) was involved
on PCBs. It is a very interesting read...
"Conductive Play-Doh" Could Herald New Materials
"A team in the U.S. has created a material
pliable like plastic but conducts electricity like a metal, shifting the foundations
of how we think about conductivity. Discovered by researchers at the University
of Chicago, the material's molecular structure is jumbled and disorderly, suggesting
it should be a poor conductor. Good conductors are generally made up of straight,
closely packed rows of atoms or molecules, allowing electrons to easily flow through
the material. A conductive material without these properties challenges a fundamental
principle of conductivity and could signify a paradigm shift in materials science.
The work is published in Nature..."
Poll: Do You Use Twitter for Business?
For a few years I have avoided using Twitter
because it had become a platform both overtly and covertly moderated by global censors
with a one-sided political agenda. Now that Elon Musk had taken the reigns, I'll
give it another try. Webmastering (a verb I just created) RF Cafe takes a lot of
time, and adding content to Twitter is not a zero-effort task, but I'm willing to
contribute some effort to it if people find it useful. A few of the recent homepage
posts have been added already, and I also created this poll to test the response.
Please take a moment to cast your vote.
Lissajous Had a Figure for It
Old sci-fi movies were famous for displaying
Lissajous patterns on oscilloscopes in hopes of portraying a futuristic look.
The first time I hooked up signals to the x and y axes of a scope and played around
with the frequencies and amplitudes, I was mesmerized by the patterns and the fact
that it was me creating them. Of course that was 30-something years ago when I was
first getting into electronics and electricity, but even today it's a cool thing
to do. In a typical, male-dominated, Chauvinistic manner, this article from the
March 1957 edition of Popular Electronics magazine delves into the subject
of Lissajous patterns. The author dares to compares men's attraction to curvaceous
o-scope figures to a similar attraction to curvaceous women. Can you imagine the
hateful feedback the editor of a current magazine would receive if something like
Get Your Custom-Designed RF Cafe
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
Many Thanks to Withwave for Long−Time Support!
Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
4-port vector network analyzer (VNA) calibrator, between- and in-series connector
adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes &
probe positioner. Special test fixtures for calibration and multicoax cable assemblies.
Frequency ranges from DC through 110 GHz. Please contact Withwave today to
see how they can help your project succeed.
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.
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 World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
Copyright 1996 - 2026
All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.
All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.