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5 of the March 2022 homepage archives. Tuesday the 22nd
 One of the many advances in radio technology
during World War II - transmission lines - is reported on here in a 1952 issue
of Radio & Television News magazine. If you are less than maybe 30
years old there is a good chance the only kind of
RF transmission line you have ever been exposed to is coaxial cable. I say 30
years old because by the early 1990s the majority of homes had either cable TV service
or rooftop TV antenna lead-ins were using 75 Ω coaxial cable rather than the
traditional 300 Ω twin lead (with the assistance of an impedance transformer
at the antenna end). Author R.C. Graham rightly credits an efficient method
of high-volume commercial polyethylene for use as a dielectric both for twin lead
and coaxial cable. Prior to that some compound of rubber or steatite (had not heard
of it, aka soapstone) was commonly used. If you are researching the history of RF
transmission lines, this article will be a valuable collection of information...
 Over the years, many companies have offered
"thumbwheel"
type devices for sliding over SMA and other connector types to make screwing cables,
adapters, attenuators, etc., on and off more convenient - especially in tight quarters.
Says Marki Microwave, "Thumbwheels provide a wrenchless method of quickly torquing
down RF/microwave test equipment. Thumbwheels are mounted around the male jacket
of all standard RF connectors and adapters. They are secured with 3 0.050" hex screws
providing a friction based grip for securing male connectors." You can't always
just "Put the wrench away" as the PDF file suggests, since sometimes a properly
torqued connection is essential, but for lab work you can't beat them. Unlike many
"thumbscrews" that have an escape slot for slipping on and off over cable, these
have no slot. Often these gadgets are handed out at trade shows, but if you ask
nicely, you might get Marki to send you one as a promotional gift.
 Although this article discusses audio waveform
measurements, the lesson learned applies equally well to any waveform frequency.
In the RF realm, we are accustomed to injecting two sinewaves at equal amplitudes
into a unit under test (UUT) and reading the relative output powers of the two input
signals and the
n-order intermodulation signals. It is usually a very simple test with simple
to interpret results handily shown on the display of a spectrum analyzer. The task
is made a bit more difficult when injecting signals of unequal strengths and especially
when measuring in units of voltage as a viewed on an oscilloscope display. I dare
say most of us need to do some head scratching and looking up of formulas to pull
off such a measurement...
 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.
 Planar Monolithic Industries (PMI), a leading
supplier of custom, high-reliability MIC/MMIC components and subsystems for applications
in space, military, communications, commercial and consumer electronics systems
for more than three decades, recently introduced. PMI is proud to introduce model
PMC-9D5G10D5G-7D6-SFF
is a Monopulse Comparator operating over the 9.5 to 10.5 GHz frequency range.
This model offers a maximum 7.6 dB insertion loss while maintaining a maximum
amplitude balance of ±0.5 dB; a maximum phase balance of ±5°, isolation of
20 dB, VSWR of 1.5:1, and Average Power Handling of 10 W. Housing is 3.48"
x 3.48" x 0.43" and has SMA Female Connectors. . Contact PMI today for more information..
Contact PMI today for more information...
 Around since 1934,
Newark Electric is one of the longest-surviving electronic component mail order
businesses. In the days before Digi-Key (founded in 1972), Newark was my go-to source
for parts I needed ASAP. Allied Electronics (earlier Allied Radio), around since
1928, was my second choice. There was no Internet, so the fastest service was had
by calling in your order - while paying a long-distance toll. U.S. Post Office and
United Postal Service (UPS, since 1907; my Uncle Brian drove their trucks from Buffalo
to/from Cleveland for 40 years) were the two prime delivery service of the era (FedEx
came online in 1973). Reportedly, its first paper-format catalog was mailed out
in 1948, two years after this full-page ad appeared in Radio-Craft magazine. Newark
now goes by the name of Newark element14 (the 14th element in the periodic table
happens to be silicon). The "About Us" webpage shows Newark and Newark element14
(in Asia) as being Avnet companies. In 1946 there were many hometown electronics
parts outlets that included repair shops, hardware stores, and department stores,
so much of what a person needed was available locally...
 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.
 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.
Monday the 21st
 This 1939 news bit from Nazi Germany overlords
illustrates the results of well-meaning citizens voluntarily surrendering their
personal freedoms and right to self defense. Nazi Party, by the way, derives from
"National Socialist German Workers' Party." Remember that when someone with Socialist
leanings these days calls you a Nazi. The 1st Amendment of the U.S. Constitution
guarantees we, the American people, a
right to free speech, and by extension, a right to listen to whatever someone
else opts to say (excluding, of course, overt and specific threats of harm). Many
generations have enjoyed that and a specific list of other freedoms, but the passage
of time has seen a dilution of those freedoms due to aggressive lawmakers and judges,
and the passive acceptance of it by too many citizens. Throughout history when citizens
yielded their freedoms to government in promise of benefits, favors, protection,
etc., they almost always found themselves on the business end of a gun (or tank,
arrow, battering ram, sword, etc.) being wielded by that same "benevolent" government.
America's founding fathers were so aware of the repeating pattern that they wrote
the 2nd Amendment into our Constitution specifically to ensure "the governed" had
means...
 This is a must-read -- "Tales
from an Engineer's Life #172: Tips on Self-Rescue from Hotel Bathrooms." Lee
Goldberg writes on the Electronic Design website of an amazing experience he had
while attempting to free himself from a hotel bathroom whose doorknob failed to
work. He alludes to Angus MacGyver, famous for his weekly TV show escapes and escapades
at the hands of bad guys. Like his hero would have done, Mr. Goldberg decided
upon a non-violent approach to the situation. Personally, there were times when
I thought "Mac" would have been justified in just shooting a villain, but the scriptwriters
thought it might tarnish his nice-guy persona. Anyway, enjoy the saga...
 Although obviously (but getting less so)
before my time, the mention of this
airborne radar surveillance system having been built by General Electric, in
Utica, New York, struck a chord since that is where I had my first engineering job
after having graduated from the University of Vermont with a BSEE degree. It seems
to me the work at the time was all done in the converted textile complex on Broad
Street. They were the glory days of GE, Westinghouse, Collins, Raytheon, and other
electronics titans whose engineers, technicians, assemblers, and program managers
changed the world. The airplanes and equipment used here were precursors to our
modern E-2 and E-3 fleet. 1956 must have been a big year for the General Electric
plant in Utica, New York, where I had my first engineering job right out of college...
 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...
 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
procedures.
Sunday the 20th
 Here is your custom made
Electrical Engineering theme crossword puzzle for March 20th, 2022. All RF Cafe
crossword puzzles are custom made by me, Kirt Blattenberger, and have only words
and clues related to 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. Enjoy!
 RF 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
(of course a gratuity will be graciously accepted). 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 quality
visitors ...
 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.
Friday the 18th
 I tried with no success using an online translator
to figure out what that line of Chinese writing is in this
Remington Rand UNIVAC computer advertisement which appeared in a 1953 issue
of Radio-Electronics magazine. If you can do the translation, please send me an
e-mail and I will add it to this page. As a historical note, Remington is the company
that made not only typewrites, but also the line of firearms and ammunition bearing
that name. The first UNIVAC (UNIVersal Automatic Computer) computer was commissioned
in 1951. Its main memory consisted of liquid mercury delay lines arranged in 1000
words of 12 alphanumeric characters each. Ironically, the speed and capability of
the UNIVAC compared to the abacus in this ad is probably about the same as that
of a modern supercomputer compared to the UNIVAC. A decade or so from now, we'll
be making the same comparison between today's computers and quantum computers...
 "When Google unveiled its first autonomous
cars in 2010, the spinning cylinder mounted on the roofs really stood out. It was
the vehicle's
light detection and ranging (LiDAR) system, which worked like light-based radar.
Together with cameras and radar, LiDAR mapped the environment to help these cars
avoid obstacles and drive safely. Since a then, inexpensive, chip-based cameras
and radar systems have moved into the mainstream for collision avoidance and autonomous
highway driving. Yet, LiDAR navigation systems remain unwieldy mechanical devices
that cost thousands of dollars. That may be about to change, thanks to a new type
of high-resolution LiDAR chip developed by Ming Wu, professor of electrical engineering
and computer sciences and co-director of the Berkeley Sensor and Actuator Center
at the University of California, Berkeley. Wu's LiDAR is based on a focal plane
switch array (FPSA), a semiconductor-based matrix of antennas..."
 It wasn't until February 1, 1972, that Hewlett-Packard
introduced its HP-35 electronic calculator. Before that, when you spoke of an electronics
calculator it referred to a computer (likely a vacuum tube type), a human who specialized
in electronics calculations (as NASA and universities referred to them), or this
special slide rule sold by Cleveland Electronics Institute - the 515-T. It had special
scales for calculating reactance, and resonance, and had common circuit analysis
formulas printed on the back side, and also came with an extensive user's manual.
This full-page advertisement appeared in a 1967 issue of Electronics World
magazine...
 ConductRF
Hand-Reformable RF Coaxial Cables are available off the shelf from DigiKey.
ConductRF FM series of Hand Formable RF cable assemblies provides system designers
with a versatile solution that allows RF cables to be physically routed and set
in to position during installation. Standard lengths and connector types feature
performance up to 40 GHz. Low loss, tinned braided cable of 0.086" diameter
with shielding of >100 dB. 100% factory tested for VSWR & insertion
loss. RoHS & Reach compliant. Ideal for internal module linking and great for
RF Testing. Made in the USA!
 Hmmmm.... at the time I marked this
stereo preamp project for posting I must have had a really good reason for it,
but now I can't recall what that really good reason was. Maybe it was simply to
mark the point in time when stereophonic electronic equipment was just beginning
to be mainstream. Oh well, somebody somewhere will do a Google search on the topic
someday and will be elated to find this. Besides, even though the use of vacuum
tubes and magnetic tape is way outdated, there is a discussion of hi-fi audio that
is still relevant. The article appeared in a 1958 issue of Radio-Electronics magazine.
Thanks for your indulgence...
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.
 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.
Thursday the 17th
 For many years in the late 1940s / early
1950s, Radio-Craft magazine ran a regular "Radio-Electronics
Monthly Review" feature that reported on industry news items. This May 1947
issue included such topics as the post-war discovery of German "teletypers" which
used a series of electrical impulses to form the numerals, letters, and symbols
by constructing them using vertical and horizontal lines. Doing so enabled symbols
other than a standard character set to be transmitted and received. It also made
the receiver/printer apparatus more compact since it only needed a few shapes for
impressing the image. Also reported was the fact that radar development cost more
overall than the cost of developing the atom bomb. In some ways that is surprising,
in other ways not. Cosmic rays and "other mysterious energy radiations" were determined
to be interfering with high altitude radio communications. Read on for more interesting
tidbits...
 "Super-conductors
- metals in which electricity flows without resistance - hold promise as the defining
material of the near future, according to physicist Brad Ramshaw, and are already
used in medical imaging machines, drug discovery research and quantum computers
being built by Google and IBM. However, the super-low temperatures conventional
superconductors need to function - a few degrees above absolute zero - make them
too expensive for wide use. In their quest to find more useful superconductors,
Ramshaw, the Dick & Dale Reis Johnson Assistant Professor of physics in the
College of Arts and Sciences (A&S), and colleagues have discovered that magnetism
is key to understanding the behavior of electrons in 'high-temperature' superconductors.
With this finding, they've solved a 30-year-old mystery surrounding this class of
superconductors, which function at much higher temperatures, greater than 100 degrees
above absolute zero. Their paper, 'Fermi Surface Transformation at the Pseudogap
Critical Point of a Cuprate Superconductor,' published..."
 Some things never change, and the basic definition
of a
pulse waveform is one of them. This article form the May 1967 edition of Electronics
World magazine does a nice job of defining the fundamental characteristics of a
pulse, including rise and fall times, overshoot, pulse width, etc. Ham shacks and
company labs alike are still stocked with the venerable HP 215A and HP 213B signal
generators that appear in this piece. If you're lucky, you can get a good deal on
them from someone on eBay...
 Sam Benzacar of Anatech Electronics, an RF
and microwave filter company, has published his March 2022 newsletter that features
his short op-ed entitled "Will
CBRS Private Networks Take Off?," where he discusses the pros and cons of moving
to the Citizens Broadband Radio Service licensed frequency band (which means paying
a usage fee) versus remaining in the licensee-free Wi-Fi spectrum. According to
Sam, benefits include greater security, less interference, and lower latency for
real-time processes. The biggest negative (other than having to pay for it) is the
relatively narrow bandwidth that can limit data rates. CBRS private networks are
only now being deployed...
 If you have a copy of EZNEC software (now
a free download), you can try modeling an end-fed "sky
wire" antenna like the one described in this article and see how it functions
when driven from a location high above terra firma when the transmitter and receiver
are connected to Earth ground via some sort of wire. Author Norman Rowe operated
from his attic as did (and still do) many Hams. Although almost any reasonable mismatch
can be accommodated with a proper matching circuit, that has no major bearing on
what the antenna radiation pattern looks like. However, the characteristics of the
ground circuit most certainly affects the antenna pattern. Surely someone like ARRL's
Joel Hallas (W1ZR, SK), an EZNEC master, could answer that without even having to
run a simulation. Come to think of it, I really don't know what a serious mismatch
does to the power factor of the voltage and current flowing in the antenna itself.
Does the relative phase of current and voltage always automatically correct itself
in the antenna? If not...
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...
 Lotus Communication Systems supplies custom,
high reliability RF/Microwave modules, IMA, and subsystems for application in Space,
Satellite, Communications, Commercial, and Consumer electronic systems. Lotus provides
custom solutions for general RF/Microwave industry, GPS/GNSS industry, Test Instrument
and other application specific markets. Each of our RF/microwave module/IMA/Subsystem
meet our exceedingly high standards of quality, and are 100% MADE IN USA. Our RF/microwave
products cover frequency band up to 64 GHz and include RF Amplifiers (LNA, MPA,
PA), Bias Network, Frequency Translator (Frequency Mixer, Multiplier, Divider, Block
up/down converter), Frequency Source (OCXO, TCXO), Passive (Coupler, Attenuator,
Filter, Divider), RF Limiter and USB Programmable RF modules (Digital Attenuator,
Signal Generator and Block Up/Down Converter).
Wednesday the 16th
 As with most things technical, Hugo Gernsback,
editor of Radio-Electronics magazine, was ahead of the curve when he wrote
of remote classrooms (Teleducation,
as Gernsback dubbed it) in this 1956 article. A big proponent of the Stratovision
and MPATI systems which employed an airborne broadcast platform for providing instruction
to classrooms across hundreds of miles. That was in the era predating satellites
(Stratovision) and the point where satellites could be used for other than specifically
designed purposes (MPATI). By 1956, though, transcontinental cable and microwave
relay systems had been built that did facilitate widespread broadcasting. Many regions
were still bypassed, but all major cities where universities and larger technical
schools were located had the capability of one-way and two-way hookups to a teaching
node...
 When I first saw this article on the
"G-Line" transmission system, I thought the cone at each end of the line was
just a gimmick to make it look high-tech. My ignorance of the way the system works
was responsible. As it turns out, the "G-line" transmission medium, named after
inventor Dr. Georg Goubau, an engineer at the renowned U.S. Army Signal Corps Engineering
Laboratories at Fort Monmouth, NJ, used the cone to transition a finite radius coaxial
cable outer conductor to an infinite radius, sort of virtual, outer conductor that
was free space. Doing so permitted a single line to do the job of carrying a signal
from point A to point B. This significantly reduced the installation and maintenance
cost of deploying a cable-based communications system - in this case for television
broadcasts in areas where over-the-air broadcasts were nearly impossible. G-line
came with many of its own unique issues, and history shows that ultimately it was
not a workable long-term solution...
 "It helped popularize the interactive computing
paradigm we take for granted today. The history of computing could arguably be divided
into three eras: that of mainframes, minicomputers, and microcomputers. Minicomputers
provided an important bridge between the first mainframes and the ubiquitous micros
of today. This is the story of the
PDP-11, the most influential and successful minicomputer ever. In their moment,
minicomputers were used in a variety of applications. They served as communications
controllers, instrument controllers, large system pre-processors, desk calculators,
and real-time data acquisition handlers. But they also laid the foundation for significant
hardware architecture advances and contributed greatly to modern operating systems,
programming languages, and interactive computing as we know them today..."
 Quaise develops millimeter wave drilling
systems for deep geothermal heat access. Our technology is the only approach in
the world with the potential to build geothermal wells at unprecedented depths and
temperatures. Quaise's technology consists of a source of millimeter wave (MMW)
such as a gyrotron operating in continuous wave mode and at high power, to vaporize
subsurface rock. Our gyrotron-powered drilling platform vaporizes boreholes through
rock and provides access to deep geothermal heat without complex downhole equipment.
Based on breakthrough fusion research and well-established drilling practices, we
are developing a radical new approach to ultra-deep drilling. Quaise is seeking
an accomplished electrical engineer or physicist with at least 5 years work experience.
Specific discipline of study and/or work in radio frequency is required, preferably
high power RF transmission over waveguide. Ideal candidate would have experience
in both the RF and high voltage (20 kV+) field...
 This crossword puzzle appeared in the May
1967 edition of Electronics World. If you happen to be an avid cruciverbalist
as am I, then you might want to try a few of the RF and microwave
engineering themed crosswords that I have been publishing weekly for two decades.
Unlike the RF Cafe crossword puzzles which contain only words and clues related
to science and engineering, these ones which appeared in various electronics magazine
sometimes use a common word to fill in where needed...
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...
 PCB Directory is the largest directory of
Printed Circuit
Board (PCB) Manufacturers, Assembly houses, and Design Services on the Internet.
We have listed the leading printed circuit board manufacturers around the world
and made them searchable by their capabilities - Number of laminates used, Board
thicknesses supported, Number of layers supported, Types of substrates (FR-4, Rogers,
flexible, rigid), Geographical location (U.S., China), kinds of services (manufacturing,
fabrication, assembly, prototype), and more. Fast turn-around on quotations for
PCB fabrication and assembly.
Tuesday the 15th
 Far more than electronics went into the
development of
color television. Extensive research into how human beings perceive color, combined
with the color-producing ability of suitable chemical compounds ultimately determined
how color picture tubes would be manufactured, and the electronic circuits which
would activate them. Most people are not aware that the very earliest color television
schemes were electromechanical contraptions that either spun a transparent color
wheel in from of a modulated light beam, or used an oscillating mirror to direct
colors to the appropriate position on a display screen. Fortunately, the fully electronic
version won. Even so, there were retro-fit kits sold and installed to convert black
and white (B&W) sets to color using the spinning color wheel system (upper left).
As recently as the late 1960s there were commercials selling a screen to place over
the front of your B&W set that was tinted green at the bottom, red in the middle,
and blue at the top...
 Talk about ESD tolerant! Get a load of that
electron beam in the process of
welding computer memory. Of course that isn't silicon - it's magnetic core memory,
the kind with tiny toroids with four extremely small gauge wires running through
them for the read and write operations. If you want a computer memory that will
survive a nuclear EMP, this is your answer. Hook it up to your electron tube computer
and you'll be playing Pong* while all the other survivors are back to tic-tac-toe
with pencil and paper! Also news in this 1967 issue of Electronics World
magazine was final testing of the Tiros weather satellite, a million-volt pulse
generator, and a multi-satellite military satellite payload being launches by the
U.S. Air Force...
 RF Cafe visitor Bob D. sent me information
on this interesting device that allows owners of vintage
AM radios to receive
FM stations while using the original tuning dial to cover the entire 88-108 MHz
band. Monsieur David Winter, of France, is the designer and seller of this
FM Converter for Vintage Radios. Installation and calibration is not for the faint
of heart, since it involves tapping directly into the circuitry and disconnecting
some of the sections where the device inserts the signal into the audio frequency
(AF) section, totally bypassing the RF and IF sections. A direct connection to the
tuning capacitor is used to tune the module throughout the FM band, which is a primary
feature of scheme. However, it requires the capacitor to be disconnected from all
other circuitry to prevent normal voltages and impedances from adjacent connected
components from entering the integrated circuit (IC). Retaining the AM reception
(and possibly shortwave reception) function requires the installer to devise a custom
switching scheme. It uses the 6.3 VAC vacuum tube (valve) heater supply. In
older radios you need to be sure to locate a "real" ground (common) point to assure
the voltage is properly referenced. The price is €29.90 ($32.83), which is currently
the cost of 7-8 gallons of gasoline...
 "How can you accurately test a
space antenna down here on Earth when it has been scaled up to penetrate the
subterranean depths of another planet? This was the question faced by SENER in Spain,
currently designing a candidate antenna for ESA's EnVision mission, which will explore
Venus from its inner core to outermost cloud layers. To solve it they lifted their
prototype skyward with a balloon. 'To develop key technologies for future missions,
ESA's Directorate of Technology, Engineering and Quality often explores multiple
approaches,' explains ESA antenna engineer Paul Moseley. 'This includes parallel
prototypes for EnVision's Subsurface Radar Sounder (SRS), which will transmit and
receive radio signals to chart the Venusian subsurface. It will achieve this using
very low frequencies (9 MHz) which in turn means its antenna has to be very
large, 16 m across..."
 The April 1967 edition of Electronics
World magazine had a series of articles about designing systems with electromechanical
relays. Even in today's world of solid state relays, there are still lots of applications
for electromechnical relays. Only a handful of American companies still make them.
The application tutorials provided herein are as valuable to today's engineers and
technicians as they were 55 years ago. This particular piece covers
operate and release times of relays. Other articles in this issue include "Reed
Relays, Time-Delay Relays," "Finding Relay Operate and Release Times," and "Arc,
Surge, and Noise Suppression."
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...
 Empower RF Systems is a global leader in
power amplifier solutions. Empower RF Systems is an established and technologically
superior supplier of high power solid state RF & microwave amplifiers. Our offerings
include modules, intelligent rack-mount amplifiers, and multi-function RF Power
Amplifier solutions to 6 GHz in broadband and band specific designs. Output
power combinations range from tens of watts to multi-kilowatts. Unprecedented size,
weight and power reduction of our amplifiers is superior to anything in the market
at similar frequencies and power levels.
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:
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2023:
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2022:
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2021:
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2019:
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2018:
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2017:
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2016:
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2015:
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2014:
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2013:
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Dec
2012:
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12 |
13 (no archives before 2012)
- Christmas-themed
items
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