Today in Science History -
to Radar" material is from the U.S. Air Force's "Air University" collection
of tutorials. I found it in a bin at Goodwill, bound along with a few other sections
by the Extension Course Institute including Electronics Fundamentals and Television
Principles. This treatise on radar is the first of those sections which will be
posted here on RF Cafe. No date is included in the document, but my guess based
on the content and drawings is sometime in the late 1950's. No mention is made of
Doppler (a 1940's development), although it was used to some degree toward the end
of World War II. The existence of over-the-horizon radar (a 1960's development)
is alluded to, but not expounded upon. The "A" in the "A-scan" radar display stands
for "amplitude;" it is an oscilloscope time-based sweep. An "A-scan" display is
what the mountaintop UHF radar operators in Hawaii were monitoring when Japanese
aircraft attacked Pearl Harbor on December 7, 1941...
"The Department of Defense (DOD) seeks innovative
and creative solutions to complex, classified challenges, but the DOD is currently
only able to access a limited pool of companies cleared to work on them. Companies
must have a facility clearance and their employees must hold security clearances
to do classified work. But for a company to have a facility clearance, it must have
a contract requiring classified work to justify the clearance. This current model
results in a cyclical pattern that precludes the injection of new companies and
ideas into the classified DOD research and development ecosystem. DARPA announced
the Bringing Classified Innovation
to Defense and Government Systems (BRIDGES) program, which aims to tap into
innovation from companies that traditionally do not work with the DOD on classified
research and development efforts. BRIDGES will connect innovators directly to the
challenging problems that exist in the classified realm so they can help develop
solutions. 'There's a large U.S. innovation talent base at small companies across
our country that we currently aren't able to tap into for solutions to classified
Here's a little more
electronics humor from the November 1961 issue of Popular Electronics
magazine. This time the topic is stereo equipment, which was a big deal in the era.
Most equipment was still of the vacuum tube variety, and the country was still enjoying
the post-Korean war and low inflation economy, so there was disposable income to
be spent on creature comforts. Hobby and home improvement magazines od the day were
filled with reviews and recommendations on receivers, speakers, phonographs, tape
players, tone arms, stylus types, cables, antennas, and all the support equipment.
Articles on room design for optimized acoustic properties included sound absorbing
ceilings, walls, and floors, speaker placement, furniture location for the best
stereo (and quadrophonic) experience, etc...
SM435C 43.5 GHz, high-performance spectrum analyzer and monitoring receiver
is now available to order. The SM435C includes a 10 Gigabit Ethernet SFP+ port,
enabling the SM435C to communicate with a PC over long distances using a fiber optic
cable. Designed for remotely-located accurate RF data analysis at the lowest cost
possible, the SM435C also includes a signed calibration certificate and a printed
packet of calibration data. The Option-80 variant of the device provides downconverter
functionality, allowing engineers working with 5G to utilize 800 MHz of continuous
real-time data for in-depth analysis. The SM435C Option-80 is also a perfect fit
for applications requiring extremely clean phase noise. The affordability of the
SM435C opens the door to industry professionals who were previously unable to attain
this power in a compact and economic package. It is available now, with a U.S. retail
price of $25,380...
"QRT" is the Q-code used in amateur radio
to tell someone to stop transmitting. Hams very much anticipated the day when Germany
and Japan would be defeated, the war would end, and they could go home to resume
their beloved radio hobby. You might know - or not - that during
World War II ham radio transmissions were prohibited in the U.S. for a
mix of reasons. Foremost was to inhibit the broadcasting of information, intentionally
or unintentionally, that might give away strategic military strategy. Innocent chatter
about whose son left for boot camp, where he was going afterwards, what his ambitions
and fortes were, which factory Mom and Aunt Rosie worked for and what they did (Auntie
was riveter, maybe), who died in service to his country, blackout hours, scrap material
recycling collections, all was potential fodder for enemy tacticians. Another reason
for the prohibition was to free up production materials and labor for the making
of military equipment. The fate of the free world depended on it - literally...
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!
Axiom Test Equipment allows you to
buy test equipment,
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
A few interesting historical statistics were
presented in this "Electronics
and Car Thievery" episode of "Mac's Service Shop," which appeared in a 1972
issue of Popular Electronics magazine. One is that steering column locks first came
out on 1970 auto and truck models. My 1969 Chevy Camaro did not have a steering
column lock, come to think of it. Also, a year earlier (1971), one in a hundred
cars in the U.S. were stolen. The aforementioned steering column lock dramatically
reduced the number of stolen vehicles. Car jacking was a thing in the early 1970's,
so that's not a relatively new crime - it's just that now we have video surveillance
everywhere so we get to see it. This story was particularly pertinent to a couple
recent experiences (not the same day) where visitors to our daughter's house locked
keys in their cars...
"For more than a decade, [Museum
of Consumer Electronics] in Solothurn, Switzerland, has been a place where history
buffs can explore and learn about the development and growth of computer and consumer
electronics in Switzerland and the rest of the world. On display are computers,
calculators, floppy disks, phonographs, radios, video game consoles, and related
objects. Thanks to a new four-year partnership between the museum and the IEEE Switzerland
Section, IEEE members may visit the facility for free. They also can donate their
time to help create exhibits; translate pamphlets, display cards, and other written
media; and present science, technology, engineering, and math workshops..."
As a life-long aircraft enthusiast, my attention
is always drawn to photos, drawings, and titles in articles dealing with any aspect
- but particularly a historical aspect - of aviation. This 1937 edition of Radio-Craft
magazine reported on the fledgling field of aircraft radio maintenance, and in particular
the opportunities presented to radio repairmen.
Aircraft electronics (aka avionics) have of course changed significantly over
the last 80 years. Accordingly, maintenance has become such a highly specialized
skill that other than swapping out entire pieces of equipment, relatively few facilities
exist that are qualified for the task. According to the article, at the time there
were a mere 5k privately owned airplanes. As of 2019, the AOPA estimated a total
of around 224k private aircraft (down from 220k in 2011), with 720k currently licensed
pilots (all categories) per the FAA...
ConductRF supports customers with all standard
RG cables, however, a very common standard is
M17/60-RG142. This cable has a solid PTFE Dielectric core over a Solid Silver
Covered Copper Clad Steel Conductor. It is double braided and has an outer jacket
of Tan colored FEP. ConductRF offers a wide selection of standard connectors including
out Type-N males which offer a coupling nut that allows both finger tightening and
torque wrench tightening. ConductRF 100% validates RF performance of these assemblies
through factory network analyzer testing prior to shipping...
In the 1930s, electricity and electronics
were mysteries to most of the population. The concepts were relatively new and few
had a firm grasp on the technology. That reality was exploited by Hugo Gernsback
during the 1934 Electrical Exposition to challenge attendees to discover how "the Mystery
Set" radio receiver sitting on the top of an empty, clear glass case was being
powered. It was a clever ruse that reportedly stumped most people. The secret is
revealed here in this 1934 issue of his Radio−Craft magazine. BTW, my guess
is that an even smaller proportion of our current citizens would be able to figure
it out, or for that matter even realize that maybe there should be a power source
of some sort...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
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...
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
The term "metallized
dielectric" at first might seem like an oxymoron. After all, if you add a conductive
substance to the dielectric of a capacitor, then you have compromised the integrity
of the dielectric as a non-conducting substance. Here's the deal: The dielectric
material between the conductive plates does not receive the metallization; a non-conductive
(dielectric) material like paper is impregnated with metal and that is used for
the plate material. The advantage of this scheme is that the plate material can
be thinner, thereby reducing the size of the capacitor package for a given capacitance
value. It comes with a price, of course, and that is a lower operational and maximum
applied voltage rating. With proper design in circuits like power supplies, metallized-dielectric
capacitors can facilitate great space savings. A major benefit of metallized-dielectric
capacitors is an ability to self-heal when the plate material develops a short circuit
through the dielectric...
3D printing of antenna and waveguide components
has been advancing rapidly in the past few years. Early research used plastic that
was then coated with a conductive substance. Once 3D printing using a metallic filament
was developed to the point that the structure could withstand heat cycling, vibration,
and shock associated with aerospace environments, the creation of complex, compound
shapes never deemed possible with traditional machining became reality. Using proprietary
additive manufacturing techniques developed in-house, virtually any form of waveguide
and/or antenna can now be fabricated by companies like
based in Switzerland. As can be seen in the included images from the
Swissto12 website, the surfaces are not perfectly
Designing, building, and tuning low frequency
filters is much easier for the person without a professional grade suite of
software, fabrication, and test equipment than is RF / microwave frequency filters.
Most of my design and integration work has been with system level transmit and receive
racks for radar and satellite earth station installations, and typically for prototyping
and/or very low quantity production. Accordingly, I often used connectorized components
cascaded together where each functional block was predefined and tested. I would
be handed a system input/output document that specified parameters for gain, phase
noise, intercept points, noise figure, group delay, bandwidth(s), power levels,
switching and settling times, current consumption, volume, weight, cost constraints,
etc. That explains why my software offerings like RF & Electronics Symbols for
Visio and RF Cascade Workbook all deal with system level design...
Altum RF, a supplier of high-performance
RF to millimeter-wave semiconductor solutions for next generation markets and applications,
announces a new grant and collaboration with Industrial Technology Research Institute
(ITRI), the largest applied technology research institution in Taiwan, and TMY Technology
Inc. (TMYTEK), a leading mmWave solution provider targeting the 5G/B5G and SATCOM
markets. Altum RF, ITRI and TMYTEK will collaborate on an
Antenna and Semiconductor Integrated Modules (AIMS) project for satellite communications
systems. The grant comes from the Eureka Globalstars Taiwan framework. The project
began in August 2022 and is slated to continue for two years. The purpose of the
AIMS project is to develop a millimeter-wave antenna-in-package (AiP) module for
phased array Ka-band satellite communication systems. Developing this module will
make satellite communication systems...
If you are from a family of electronics hobbyists
and/or professionals, then there is a good chance your grandfather and possibly
even your father kept a handy-dandy list of common
circuit design formulas handy. The list here Part 2 includes all the formulas
on this page, which dealt primarily with vacuum tubes, the schematics for which
were presented in Part 1 of the series. There was not an "app for that" back in
those days. Prior to a smartphone in every pocket, notes were pinned to a lab wall
or kept in a hand-written notebook...
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...
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
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
This is one of the few times I disagree
with Hugo Gernsback. It's not that his conclusion about economics being the reason
in producing promised newfangled radios after the end of World War II is
wrong. My problem is that he excuses the manufacturers who blamed delays on the
large amount of time and effort required to incorporate all the new technology developed
during the war. As Radio-Craft magazine reader C.G. Little wrote in this August
1946 issue, companies were running advertisements a year before V−E Day (May 8,
1945) promising to have all-new radios with wonderful new technology developed from
advances made in radio and radar during the defeat of Axis forces. Japan surrendered
on V−J Day (September 2, 1945). The fact is those companies had a year to prepare,
and the U.S. government was gradually relinquishing control over production facilities
as the War Powers Act impositions faded. Nobody was taken by surprise. This was
either a case of government-backed propaganda, or false advertising by the manufacturers...
An Electronics Weekly article entitled
Grid Effects of Electric Vehicle Charging in the Next Decade" references
Nature magazine study "Charging Infrastructure
Access and Operation to Reduce the Grid Impacts of Deep Electric Vehicle Adoption,"
which indicated high density areas with currently (no pun intended) stresses electric
supply grids will be problematic. It is a Captain Obvious announcement to anyone
following the existing issues like a couple weeks ago California telling EV owners
not to charge their cars because of the power shortage. It begins: "Researchers
at Stanford University have modelled over-night home charging of electric vehicles
and predict that it is not the correct strategy, for the Western US, at least. Stanford
EV charging model Simulation is based on a model, revealed in March, for charging
demand that can be applied to different human populations under different conditions.
In a demonstration..."
For several years I have been scanning and
posting Radio Service Data Sheets like this one featuring the
RCA Victor Model R-78 B1-Acoustic 12-Tube Superheterodyne floor console radio
in graphical format, and run OCR on them to separate the textual content and make
it searchable. 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. I will keep a running list of all data sheets to facilitate a search.
The RCA Victor Model R-78 B1-Acoustic 12-Tube photo was found on the RadioMuseum.org
Included in this first of a series of the
Mathematics for the Serviceman" articles that ran in Radio-Craft magazine is
another "cheat sheet" full of oft-used formulas. It begins with basic Ohm's law,
resistance, inductance, and capacitance, then builds from there. What was valid
in 1930 is still valid in 2022. See the October 1930 issue for the next installment
that includes yet another handy-dandy cheat sheet of formulas. A couple examples
I learned a new word in this issue of
Electronics World magazine's special report on
ceramic capacitors: "discoidal." It looked like a made-up word to describe something
that looks like a disc. Anyway, the July 1965 issue contained a collection of articles
on the various sorts of capacitors in use at the time. Other types of dielectrics
covered were tantalum, glass, plastic-film, mica, paper, and metallized-dielectric.
Ceramic and electrolytic capacitors were by far the most widely used capacitors
during the vacuum tube era since they were relatively inexpensive to manufacture
and could handle high voltages. Hobbyists who service and/or refurbish vintage electronic
equipment still need this information if for no other reason than to verify component
values based on color codes. It also helps to know how the electrical properties
vary over temperature, frequency, applied voltage, etc., when deciding which type
of modern capacitor will best serve as a suitable substitute...
Any day now we'll see a headline about a
FBI) raid on Scott Adams' home at 6:00 in the morning to confiscate his cellphone.
Evidently it's not OK to poke fun at the "woke" agenda according to (as of now)
77 newspapers which cancelled the "Dilbert"
comic strip. Many newspapers have gone out of business or are on the verge of doing
so due to disappearing subscribers. People are sick of having one view forced at
them with no counterpoints. I'm sure Adams makes plenty of $$$ from other Dilbert-related
ventures, so he probably will not miss the revenue. A lot of people still subscribe
to newspapers mainly for comics and puzzles. This will just add to the "go woke
- go broke" phenomenon we're witnessing happening to politically correct businesses.
Go to Dilbert.com for all your Dilbert needs.