See Page 1 |
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4 | 5 of the February 2021 homepage
archives. Friday the 5th
 This
Engineering and Physics Theme crossword puzzle for February 7th
contains only words and clues related to engineering, mathematics, chemistry, physics,
and other technical words. 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., Hedy Lamarr or the
Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
 Although not specifically stated, some of
the technology reported in this August 1945 issue of Radio-Craft magazine
was not so long before classified technology developed during World War II.
The
Radiotype system of wireless teletype developed by General Electric
was an early attempt to provide a mobile means of sending and receiving hard copy
messages. It was a rather complex scheme that used a typewriter to drive a tape
punching apparatus, which was fed into a radio transmitter to send coded tones (as
opposed to CW pulses) for a receiver to then decipher and drive an Electromatic
typewriter. The demonstration used a police car to carry remote equipment. In related
news, RCA's wireless 488 word-per-minute (wpm) telegraph multiplexer using time
division multiplexing (TDM) Also featured was the FCC's decision to move the commercial
broadcast FM band from 54-88 MHz up to 88-106 MHz (now up to 108 MHz...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
 "In 2020, a project between AMSAT-UK, AMSAT-NL,
and Swiss universities got under way with the aim of equipping two Swiss satellites
- for now under the CHESS name - with linear
amateur radio transponders. Linear transponders permit several
CW or SSB contacts to take place simultaneously within a prescribed passband. The
satellites also include features for classroom demonstrations and experiments. The
CHESS (Constellation of High Energy Swiss Satellites) project includes two satellites,
which will be built simultaneously and later launched as a constellation. 'The main
science objective is to improve the understanding of the upper atmosphere by in-situ
measurements..."
 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 ...
 When you think of "pirate radio," most likely what comes to mind is a rogue, unlicensed
transmitter that is re-broadcasting copyrighted material, syndicated shows, etc.,
on radio or television. Nowadays that would also include the Internet as a medium.
Did you know that, at least decades ago, the British government (and maybe others)
charged citizens a fee for listening to broadcasts on their household radios? That's
right, if you wanted to listen to the BBC, you would kindly remit a fee of 10 shillings
($2.50 in U.S. dollars at the time) per year. Otherwise, you were apt to have government
inspectors descend upon you and padlock your radio set - or collect the requisite
10 shillings on the spot. After a growing number of suspected dishonest British
subjects finally exceeded the reasonable level of tolerance of the government, a
clever scheme was devised to trick evil citizens into divulging their nefarious
crimes. Author Austen Fox does a great job of telling the tale. The stunt would
make a good candid camera ploy for a good laugh today, but in the 1930s when radio
waves were mysterious and even feared...
 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.
The AB829B1038 is an 829 MHz High Performance LTE Band Cavity Band Pass Filter.
It features a very sharp transition between the passband and the rejection frequencies,
an attenuation of 40 dB minimum 1.5 MHz away from the band edges. The
AE2075-5125DB5458 is a 1650-2500 MHz/4400-5950 MHz Duplexer. Isolation between the
bands is greater than 70 dB. Custom RF power directional coupler designs can
be designed and produced when a standard cannot be found...
 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.
Thursday the 4th
 It has been a long time since I've had a
citizens band (CB) radio in my car. Back in the 1970s when the
CB craze was at its peak, with songs like C.W. McCall's "Convoy"* topping Casey
Kasem's American Top 40 (AT40) charts, my high school compadres were all installing
23-channel CBs (standard at the time) in their cars and pickups. I joined in with
a Radio Shack unit (don't recall the model number). In those days the FCC required
operators to register and mail a check for a few bucks - same with radio control
(R/C) systems for model airplanes also operating in the same 26-27 MHz radio
band - in return for a "Citizens Radio Station License" document to carry in your
wallet. Most CB channels were spaced at 10 kHz, but the R/C frequencies were
in-between some CB channels spaced at 20 kHz. For instance, my 3-channel OS
Digitron R/C system was at 27.195 MHz, which resided between CB channels 19
(27.185 MHz) and 20 (27.205 MHz). Some electronically savvy CBers would
illegally modify their radios to include operation on those in-between frequencies
(e.g. Ch 19A at 27.195 MHz), thereby creating a scenario where merely keying
up the transmitter could "shoot down" a model airplane if close enough...
Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products such
as RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters.
Since the conception of WFT, we have introduced products that have been purchased
by a wide range of customers, from hobbyists to education facilities to government
agencies. Worldwide customers include Europe, Australia, and Asia. Please contact
Windfreak today to learn how they might help you with your current project.
 "The Air Force is looking into flipping the
cost curve when it comes to defeating adversaries by focusing on electronic or nonkinetic
capabilities as opposed to missiles. 'In some aspects, an electron is much cheaper
than a very expensive missile,' Gen. Charles Brown, chief of staff of the Air Force,
said during a January 27 web event hosted by the Association of Old Crows. 'We've
got to think about the cost curve' and be able to do both the kinetic and nonkinetic.
Brown acknowledged that the Air Force has been 'asleep at the wheel' for the last
25 to 30 years when it comes to operations in the
electromagnetic spectrum. Sophisticated adversaries have noted
the spectrum is critical for U.S. forces and have sought high-tech methods to deny
it..."
 We know, many times you want to just buy
your RF assemblies to plug in to your
Circular D38999 Connector or your VITA67 module. Well know ConductRF
offers multiple solutions for both styles of Multi-Port connector all available
on short lead times based on our on hand materials stock. D38999 integrates BMA,
SMPM & SMPS Connectors, also other #8, #12 & #16 Coax Contact solutions.
VITA67.1/2 uses SMPM solutions, but the new VITA67.3 also offers SMPS and NanoRF
to support your coax requirements. These are 100% factory tested to exacting VSWR
and Loss standards because, We know, Results Count!
 While recently watching the classic film
"The Longest Day," about the June 6, 1944 D-Day invasion, I paid particular
attention to the electronics being featured. During World War II, means of communications
were nowhere near as ubiquitous as they are today with cellphones, the Internet,
and readily affordable, high quality portable Ham gear. Large, heavy radio, teletype,
and radar gear made portable by equally large and heavy batteries, often significantly
hampered progress under fire. As illustrated in the movie, relying on easily cut
or blown up landlines caused significant loss of strategic capability. Thousands
of experienced Amateur Radio operators provided the Allied forces with out-of-the-gate
communicators and electronics technicians. Many had, prior to enlisting, donated
some of their equipment and components to the Department of War for use, ultimately,
in securing victory...
 Artech House today announced the publication
Introduction to LabVIEW FPGA for RF, Radar, and Electronic Warfare
Applications by Terry Stratoudakis. Real-time testing and simulation of open-
and closed-loop radio frequency (RF) systems for signal generation, signal analysis
and digital signal processing require deterministic, low-latency, high-throughput
capabilities afforded by user reconfigurable field programmable gate arrays (FPGAs).
This comprehensive book introduces LabVIEW FPGA, provides best practices for multi-FPGA
solutions, and guidance for developing high-throughput, low-latency FPGA based RF
systems. It provides real-time testing and simulation of open- and closed-loop RF
systems for signal generation, signal analysis, and digital signal processing that
require deterministic, low-latency, high-throughput capabilities presented by user
reconfigurable FPGAs. Written by a recognized expert with a wealth of real-world
experience in the field...
 NorthEast RF's comprehensive
antenna testing services include linear | circular polarized antenna
measurements and OTA cellular device pre-compliance. Up to 18" diameter and <10
kg weight. Antennas can be rapidly evaluated and optimized using our fast near field
spherical system. Test results supplied in data file with pattern viewer software.
A picture of the test configuration is included to help aligned axis. Our selection
of human head and hand phantoms are ideal for verification of body worn devices.
Turnaround time is usually 3-days.
Wednesday the 3rd
 Many times, especially after reading an episode
of "Mac's Radio Service Shop," I start thinking of how I would have liked to have
owned an electronics shop back in the golden age of radio and, to a lesser extent,
television. A person would have to be really sharp with circuits and test equipment
to be successful because every component of every part of the assembly was discrete
- no integrated circuits. You needed to be able to troubleshoot and repair the power
supply, RF, IF, and baseband sections, video, audio, and demodulation - everything.
You also needed to be smart enough to keep yourself from getting killed by the high
voltages floating around in the chasses. What makes me think twice about wanting
the business is the subject of this installment, "Customer Cussedness." Dealing with idiots would be harder to take
than the worst head-scratcher electronics problem. While at Westinghouse Oceanic
Division in Annapolis, Maryland, I had the privilege of knowing a fine fellow named
Wilson Roe...
 The Far Side, by
Gary Larson has always been my favorite weird-wit comic strip that often took shots
at scientists and mathematicians, and many have tried to replace it after it ended
in on January 1, 1995. "Loose Parts,"
drawn by Dave Blazek, comes the closest IMHO. This one from February 11, 2020 is
a great example of the kind of material he comes up with. You can scroll through
other panels from the link.
 3D.directory is the largest directory of
3D Printing companies on Internet. We have listed 3D Printing, 3D Scanning and 3D
Design companies from around the world and made them searchable by their location
and capabilities. RF Cafe page:
3D Printers and Fabrication
If you would like your company listed, please look through the
RF Cafe Vendor Pages
topic list and send me an e-mail with company name and contact information (city,
phone, URL), and a brief description (see pages for examples).
 "A new machine learning approach could improve
radar performance in congested environments. Researchers from
the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army
Research Laboratory and Virginia Tech developed an automatic way for radars to seamlessly
operate in congested and limited spectrum environments created by commercial 4G
LTE and future 5G communications systems. 'Future implementations of this algorithm
into Army legacy and developmental radars will provide unprecedented spectrum dominance
for soldiers,' said Army researcher Dr. Anthony Martone. 'This will enable soldiers
to use their radars for problems such as tracking incoming targets..."
 Berkeley Nucleonics Corporation (BNC - like
the connector) will be conducting a free webinar on Thursday, February 25th, entitled
"Quantum Computing." To most people, including me, quantum computing
is still a mysterious technology. Its concepts of multiple simultaneous logic states
makes the fuzzy logic craze of the 1980s look sharply focused. Photos of quantum
computers built by IBM*, Microsoft, and Google look like science fiction chandeliers
where you expect to see the rejuvenated brains of Albert Einstein, Galileo Galilei,
or Isaac Newton soaking in a bubbling bath of formaldehyde with wires sticking out
of them. A short paper entitled, "Are You Ready for Quantum Computing" can be accessed
on the BNC website. Berkeley Nucleonics produces a number of instrumentation items
used by quantum computing researchers...
 Aluminum wire's role in electronics and
electrical service systems is an interesting case study. Early on, as this 1948
Radio-Craft magazine article reports, aluminum was seen as a panacea for harder
to find copper sources and attendant price increases. Back in the early 1970s when
I first began working as an electrician while taking vocational courses in high
school, aluminum wire was being installed in low-end tract homes, apartments, and
townhouses in order to save a little money. Usually, you needed to go one size up
(12 ga. for 15 A circuits instead of 14 ga.), but the cost was still
less. The National Electric Code (NEC) permitted it at the time because it had not
been in service long enough for its cold flow nature to manifest itself through
loosening connection interfaces and eventual fires due to sparking under load. Brittleness
after repeated stressing also caused arcing and resulted in fires, as did corrosion
brought on by dissimilar metals...
 A new
report was recently released by the EMP Task Force on National and Homeland Security
entitled, "Russia: EMP Threat - The Russian Federation's Military Doctrine,
Plans, and Capabilities for Electromagnetic Pulse (EMP) Attack." Despite the
official-looking organization name it is a private research group, but often outside-Washington
research informs on world events more completely with unfiltered data. We know EMP
events are capable of instantly crippling vital infrastructure by inducing damaging
currents and voltages in and onto, respectively, power supply lines (and consequently
the devices connected to them), as well as disconnected devices (battery-powered
items). This is not tinfoil hat conspiracy theory like mind control via cell tower
radiation and chemicals in the drinking water. Lots of effort goes into war-gaming
EMP scenarios by DHS, DoD, DoE, et al. Having a vacuum tube radio and a vintage
computer-free truck won't help you for long with no electricity to charge batteries
or to run gas pumps.
 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 2nd
 Good
power supply design has always been key to good system function.
As with so many other topics in electronics, the basics of power supply design are
the same now as they were in 1945 when this article appeared in Radio-Craft
magazine. We now have transistors rather than vacuum tubes, but otherwise issues
of voltage regulation, current supply, ripple, and power dissipation remain. Off-the-shelf
power supplies have been and are available where engineers have designed generic
or special purpose units with a set of specifications which a system designer uses
to integrate them into their products. Many times, though, it is necessary or preferred
to have the power supply on the same circuit board or in the same enclosure as the
functional part of the product, so it is up to the designer to do it all...
 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.
 "The U.S. Department of Defense (DoD) has
released a plan to counter the increased threats posed by the proliferation of
small drones commercially and by militaries. In a 36-page strategy
released on January 2021, strong emphasis has been placed on inter-agency cooperation
in the federal government to develop a baseline of knowledge, solutions, infrastructure,
and response to counter small, unmanned aircraft systems (sUAS) threats. Small drones
have become increasingly affordable and portable with growing capabilities, such
as the ability to swarm and carry out cyberattacks, all of which could be enhanced
with the use of artificial intelligence and autonomous systems..."
 EMC Directory is the largest directory of
EMC / EMI Testing companies on Internet. We have listed the leading EMC / EMI companies
from around the world and made them searchable by their location and capabilities
- emission testing, immunity testing, CE/FCC marking certification etc. RF Cafe
page: EMC /
EMI / RFI Manufacturers & Services
If you would like your company listed, please look through the
RF Cafe Vendor Pages
topic list and send me an e-mail with company name and contact information (city,
phone, URL), and a brief description (see pages for examples).
 You've heard of
"Litz" wire, right? It's the twisted bundle of multiple enamel
or otherwise coated wire used for making couplers, antennas, and at frequencies
up to about a couple MHz. Congratulations, but did you know the full name for it
is "Litzendraht?" Neither did I until after reading this article. Litzendraht does
not derive from the surname of a fellow named Otto or Wolfgang Litzendraht, but
is the German word meaning "braided wire" or "woven wire." Litzen by itself means
braided or stranded. So, technically if you call it Litzendraht wire, you are being
redundant since it is the same as saying woven wire wire. That might save you some
embarrassment one day if you happen to be working around a German techie. Litzendraht
is used in order to exploit the skin effect at high frequencies where the majority
of the current is conducted on the wire's surface. Using multiple insulated wires
enables greater current carrying capability...
 Artech House today announced the publication
of
EW 105: Space Electronic Warfare by David L. Adamy. The fifth
book in the bestselling Artech House EW 100 series explores electronic warfare (EW)
in space. Practical problems – including intercept and jamming of hostile signals
transmitted from the Earth's surface and the vulnerability of satellite links to
attack from the Earth's surface are discussed. Spherical trigonometry is covered
to provide the background necessary to understand the scope of satellite problems.
Orbit mechanics, specifically the way the Earth and its satellites revolve around
one another, is also explained. The basics of radio propagation and how it applies
to communications Electronic Warfare are demonstrated, as well as the special considerations
that apply to radio transmission to and from an Earth satellite. Satellite links
and link vulnerability are discussed. New Release Price: $96
 LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
Monday the 1st
 Here is an interesting photo montage of many
ground-breaking events in the
history of radiotelephony, which appeared in a 1939 issue of
Radio News magazine. A mere 35 years had passed since Guglielmo Giovanni
Maria Marconi sent and received his first wireless signal in the attic of his house.
The equipment might seem crude compared to today's technology - and it is - but
it is miraculous considering both the electrical and mechanical ingenuity that went
into producing it. Engineers, scientists, technicians, manufacturing specialists,
and managers from (primarily) the U.S. and Europe combined their collective genius
and determination to advance the state of the art at a blinding pace. Many of you
have seen some of these pictures before. An identification key to each is provided...
 "PCBONLINE, a custom advanced circuit board
manufacturer, has recently published an AutoDesk Eagle tutorial. The step-by-step
guide demonstrates
how to create a PCB using the software. First, it explains the
program control panel, the schematic window, and the board window. Then the tutorial
tells how to create a new project, add parts, add connections between parts, name
and label the nets, provide parts with value, check the electrical rules, and route
the board. If you're new to PCB design or use AutoDesk Eagle, this comprehensive
guide should be beneficial. When you're done with PCB creation, you can have circuit
boards made by PCBONLINE, which checks your Gerber and BOM carefully and provides
free tech support..."
 I like a good clean joke as much as the next
guy, and Design News has a good collection of them in its "Engineering
Humor for the Ages" slideshow, but this "Types of People" totally misses the mark.
The traditional form states, "There are 10 kinds of people in the world - those
who understand binary and those who don't." It appears the writer is the latter
type of person. Take a look and see what I mean. The "Engineering Units" section
includes some really good ones I have not seen before, but this seems wrong "1000
aches: 1 megahurtz" (should be "1 kilohurtz"). The entire presentation
begins
here. Here is
my favorite. Need more? There are scores of
engineering and science humor pages
here on RF Cafe.
 It's hard for most people alive today to
imagine a time when
vacuum tubes were the only means of amplification and rectification
available. The discovery and application of semiconductors as replacements was a
huge step forward for all but the highest power applications like megawatt power
amplifiers. Equally hard to imagine is having to design circuits without the aide
of computers - or at least a digital calculator. Parameter tables and slide rules
were de rigueur for the day. Power supplies in the hundreds of volts were commonplace
and printed circuit boards were a platform of the future. Point-to-point wiring
ruled the day. Other than for special cases like traveling wave tubes (TWTs) and
microwave magnetrons, there are not many engineers left that design tubes. As with
a lot of the vintage methods and equipment, it is amateur hobbyists who keep the
art of tube circuits alive. The Internet is full of projects and articles on tube
design...
 Exodus Advanced Communications' broadband
AMP2070C Solid State Power Amplifier (SSPA) is designed for broadband
EMI-Lab, Communications, and Electronic Warfare (EW) applications. Its Class A/AB
linear design accommodates all modulations & industry standards. It covers 700 MHz
– 6.0 GHz, produces 100 W Minimum, 50 W P1dB, with a minimum 50 dB
Gain. The AMP2070C exhibits excellent gain flatness, optional monitoring parameters
for forward / reflected power, voltage, current & temperature sensing for superb
reliability and ruggedness. Integrated in our compact 3U chassis weighing <25 kg.
Rack-mountable with dimensions of 430 mm x 133 mm x 560 mm...
 MPDevice (MPD) has become a trustworthy
and reliable company in the global RF market as a manufacturer of
passive RF devices.
Included are attenuators and terminations, coaxial connectors, adapters, and cable
assemblies, DC blocks, surge arrestors, power combiner / dividers, and directional
couplers. The Korean Telecommunication market is now entering into the era of hyperconnected
society. With continuous enhancement in R&D capabilities and quality control,
MPD will continue in an effort to become the No. 1 technologically innovative
company with a focus on the emerging 5G marketplace.
These archive pages are provided in order to make it easier for you to find items
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way to find anything on the website is to use the "Search
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