Participate in this ground breaking, virtual
international amateur radio expo. Packed with world renowned speakers, exhibitors,
and special conference rooms built on a virtual reality platform. Attend from the
convenience of your desktop, laptop, tablet, or smartphone.
QSO Today Virtual Ham Expo coming to
your laptop, tablet, and smartphone on: August 8th and 9th (that's this weekend).
QSO Today called on its former guests and other expert amateur radio operators to
create an amazing series of lectures in webinar format from one of our five virtual
lecture halls. All lectures are: Fully live interactive with speaker during the
session hour, Completely downloadable after the weekend, Collateral materials are
downloadable in PDF format, Everything available up to 30 days.
Computer analysis in 1976 was a job performed
on a corporate, university, or government mainframe. Radio Shack's TRS-80 came out
in 1977, but it did not have the capacity to calculate and plot antenna gain charts
like the one in this QST article. Yes, an ambitious programmer could write
the code necessary to perform the double integrals presented in the article, but
to do all the figuring needed to create all the graphs in Figure 4, the job would
just about be finishing up today - and that's not too much of an exaggeration. For
some reason the authors never mention what computer was used or where it was based.
When I saw the title of "Loops vs. Dipole,"
I expected the loop to be round or square, but for analysis purposes it was modeled
as a pair of parallel elements representing the horizontal components of a square
loop antenna. Justification for omission of the vertical sides...
Mr. Chris B., a colleague of mine at
Comsat, in Germantown, MD, way back in the early 1990s, was/is a big fan of vintage
audio and video gear and test equipment. In fact, he worked at a sideline business
repairing vacuum tube equipment. Chris was also a semi-rigid coax cable bending
and routing master if memory servers me. He visits RF Cafe on a regular basis because
of the article post from last-century electronics magazines. Anyway, he sent me
a link to a story about the first documented use of magnetic tape (Ampex quad videotape)
in 1956 for time-delaying east coast broadcasts to equivalent time slots on the
left coast. Prior to that, kinescopes were used to relay broadcasts live so the
6:00 pm and 11:00 pm east coast news broadcasts from ABC, CBS, and NBC
were shown at 3:00 and 8:00, respectively, in LA and Seattle. Prime time shows ran
from 5:00 - 8:00 pm Pacific time, which was very inconvenient to the locals'
schedules. Here is a 1958 Radio-Electronics article entitled, "4-Track
Stereo Tapes Coming."
Since 1961, MECA
Electronics has designed and manufactured an extensive line of
RF & microwave components
for in-building, satellite, radar, radio, telemetry, mobile radio, aviation &
ATC. Attenuators, directional & hybrid couplers, isolators & circulators,
power dividers & combiners, loads, DC blocks, bias-Ts and adapters & cables.
MECA has long been the 'backbone' of high performance wired and air-interfaced networks
such as in-building applications, satellite communications, radar, radio communications,
telemetry applications, mobile radio, aviation & air traffic communications.
"Drone technology offers a powerful way for
enterprises to conduct
remote asset inspections during and after the Covid-19 pandemic. The demand
for drones among enterprises is forecast to continue to grow over the next few years,
with Gartner predicting that shipments of enterprise drones will reach 1.3 million
by 2023. Telcos and MNOs are already leveraging drone technology to automate cell
tower inspections, boost operational efficiency, and accelerate the rollout of 5G
infrastructure. As connectivity improves and automation increases, we can expect
to see drones at the edge, completing autonomous missions, and uploading data directly
to the cloud, bringing substantial business benefit to telcos and other enterprises..."
San Francisco Circuits (SFC) shares in a
recently published article entitled, "The
Importance of PCB Trace Widths in PCB Design," that there are a variety of applications
that demand specific trace layout characteristics and how or when to incorporate
them into PCB designs. A specific PCB application will determine trace widths and
trace types in a PCB design and a balance should be maintained between PCB fabrication
cost, board density/size, and performance. The purpose of a PCB trace is to connect
any kind of electrical signal - analog, digital, or power - from one junction to
another. And if a PCB has specific design requirements such as speed optimization,
noise or coupling mitigation, or high current/voltage, the trace widths and types
might be more important than optimizing for manufacturing cost of the bare PCB or
overall board size...
If I told you that Lester William Polsfuss
is widely credited with being a major player in the pioneering of electric guitars
due to his solid-body (no acoustic resonance chamber) designs, you might wonder
where I came up with that claim. However, if you know that Mr. Polsfuss is the surname
of Les Paul, then you would quickly agree. As if being a popular musician and, along
with wife Mary Ford, selling millions of records wasn't enough, Les Paul was also
an experimenter and inventor in the electronic music realm. This article entitled
Paul: Technician and Musician" appeared in a 1958 article in Radio-Electronics
magazine, and was at the time a contemporary look inside his home-workshop-studio,
when he was first gaining popularity...
Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave
connectors, between-series adapters, RF components and filters for wireless
service providers including non-magnetic connectors for quantum computing and MRI
equipments etc. ISOTEC's product line includes low-PIM RF connectors components
such as power dividers and directional couplers. Off-the-shelf and customized products
up to 40 GHz and our low-PIM products can meet -160 dBc with 2 tones and
20 W test. Quick prototyping, advanced in-house testing and high-performance.
Designs that are cost effective practical and repeatable.
Even with having been granted more than
400 patents in his lifetime, and being a major player in the realms of energy, data
storage, and semiconductor research and manufacturing, you - as well as most people
- have probably never heard the name
Stanford Ovshinsky. He was somewhat of a celebrity in the 1960s and 1970s when
working hard to promote his concept of "glassy semiconductors," - aka Ovonic devices.
Ovonics are amorphous materials that are used for making switches for digital logic
and memory devices. Either the Ovshinsky process did not pan out for high volume
commercial production or some other technology displaced the what it was hoped to
"The FCC has issued
a Forfeiture Order (FO) calling for
HobbyKing to pay a fine of $2,861,128 for marketing drone transmitters that
do not comply with FCC rules. An FCC Enforcement Bureau investigation stemmed in
part from a 2017 ARRL complaint that HobbyKing was selling drone transmitters that
operated on amateur and non-amateur frequencies, in some instances marketing them
as amateur radio equipment. The fine affirms the monetary penalty sought in a June
2018 FCC Notice of Apparent Liability (NAL). The FCC said its investigation found
that dozens of devices marketed by the company transmitted in unauthorized radio
frequency bands and, in some cases, operated at excessive power levels. 'Such unlawful
transmissions could interfere with key government and public safety services, like
aviation systems,' the FCC said.'We have fully considered HobbyKing's response to
the NAL, which does not contest any facts..."
One of the Notable Tech Quotes which has
appeared on RF Cafe is, "The nice thing about standards is that you have so many
to choose from," by computer scientist Andrew Tanenbaum. In the middle of the last
century, a change in the fundamental understanding of current flow precipitated
what has become a very large opportunity for people to misunderstand descriptions
current direction caused by a difference in voltage potential (voltage) - depending
on the era a particular description was written. Beginning with Benjamin Franklin,
electron current flow was assumed to be from positive to negative, ostensibly but
incorrectly, because a positive thing must contain an excess of something (charge
carriers - electrons) and a negative thing must have a deficiency. Hence, current
flowed from an excess source to a deficient sink. We now know that negative things
contain more electrons (relatively) than a positive...
RF Cascade Workbook 2018 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. 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...
"As the EV market grows, so does demand for
robust magnetic field sensors within these vehicles. Stray magnetic fields may diminish
the accuracy of these sensors, though, which is where active stray-field compensation
comes to the rescue." So begins Frederik Berstecher in his article entitled,
Overcome Stray Magnetic Fields with Active Stray-Field Compensation, posted
on the Electronic Design website. Continuing, "The electric-vehicle market
continues on a serious upswing: Allied Market Research forecasts show it will reach
$802.81B by 2027, up from $162.34B in 2019 [can they
really estimate to 5 significant digits? - KRB]. Such growth also pushes
the need for additional magnetic field sensors within these vehicles for position
detection. The sensors are robust enough to withstand a variety of harsh environmental
conditions, temperatures, vibrations, and water and dust..."
Withwave has announced a new precision
SMPM Adapter Series for DC to 67 GHz. These SMPM Series are designed based
on precision microwave interconnection technologies up to 67 GHz. These SMPM(F)
to SMPM(F) with bullet type and SMPM(M) to SMPM(M) are manufactured to precise microwave
specifications and constructed with female and male gender on both sides. The precision
microwave connector interfaces ensure an excellent microwave performance up to 67
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.
The "Monthly Review" column appearing in
Radio-Craft magazine was an assorted collection of news tidbits about
electronics and communications industry happenings, similar to contemporary
magazines. Looking back to 1947, the world was hopeful about the future as World
War II was finally over and even the loser countries were focusing on how their
societies would be shaped by technology and lessons learned in the preceding seven
to ten years (depending on when a country entered the war). Two items here are particularly
interesting because they refer to ongoing research into large screen televisions
and video phones (aka "televisers"). Large screens at the time meant either much
bigger cathode ray tubes (CRTs) or projection systems - both of which came to fruition
in the 1960s and 1980s, respectively. Plasma screens, then LCD and finally LED screens
mark the eventual evolution...
pSemi® Corporation, a Murata company focused
on semiconductor integration, announces the expansion of its
step attenuator (DSA) portfolio with two new high-performance DSAs, PE43610
and PE43614. Featuring industry-leading attenuation accuracy, the PE43610 and PE43614
DSAs support the entire 9 kHz-13 GHz and 9 kHz–45 frequency
ranges, respectively. Ideal for 5G test-and-measurement applications, these DSAs
exemplify pSemi's high-performance capabilities at mmWave frequencies, maintain
monotonic response across the entire frequency range and feature high linearity
and fast switching time. Offered in a 24-lead 4x4 mm LGA package, the pSemi PE43610
and PE43614 DSAs feature industry-leading attenuation accuracy, fast switching times,
wider frequency band coverage than competitors, and high linearity...
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.
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. 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...
Since the International Microwave Symposium
(IMS 2020) is completely virtual this year, I figured maybe re-posting my coverage
of the Microwave
Museum display of vintage industry research and development items would fit
right in. The photos were taken during my attendance at IMS 2009 in Boston,
MA. At the time, they were the only photos of the collection on the WWW. It had
a very nice display of items from the early days of radio and radar. According to
the IMS 2009 website, the items are "memorabilia from the first IMS held in Boston
50 years ago." Most displays were glass cases, so it made getting useful photographs
difficult because of glare and reflections. You will see some of that in the images
here. More information can be found on the National Electronics Museum website...
Southwest Antennas, a leader in rugged
RF and microwave antenna products and accessories for tactical radio systems,
is pleased to announce the release of four new dual-band sector antennas designed
for use with multi-port MIMO and MANET radio networks. The innovative dual-band
sector antenna design allow these antennas to operate across two distinct frequency
bands, enabling dual-band transmit and receive capabilities when paired with radio
systems capable of multi-band operation. Dual-band operation allows for many advanced
network configurations and features, including rapid band-switching for anti-jamming
applications in contested RF environments, separating network traffic by band based
on environmental operating conditions...
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.
TotalTemp Technologies is proud to introduce
SCC98-NR Thermal Platform System. Our newest thermal platform system designed
for efficient conductive thermal testing has a 15 x 6.5” active surface. It has
fast cooling to -70°C using only electricity, no expendable coolants. Very fast
heating to +150°C. System is shown with under bench condensing unit which saves
benchtop space. Features award winning Synergy Nano programmable temperature controller
and 2−Year Warranty. Alternate sizes, and many custom features available to best
meet your requirements. Primary Features & Benefits: Fast temperature transition
rates – comparable to some cryogenic systems, Proven, industry standard ultra-low
temp refrigeration system...
this for a great anagram? International Microwave Symposium = Comparatively Winsome
Ruminations, or maybe Unwise Improvisational Commentary. I came up with that today
when noting that IMS 2020 Virtual
Event begins today. An anagram, BTW, is a word or words created from the letters
of another word or words. Some results are very descriptive of the original subject
(Western Union = No Wire Unsent and The Morse Code = Here Come Dots), but the best
are results that mock (New York Times = Monkeys Write) or suggest the opposite of
the original. Here's another: Electrical Engineer = Career Intelligence. There are
many anagram finders out there, including AnagramMaker.com, which is the one I used
to find my International Microwave Symposium anagram...
"According to a report by Recon Analytics
4G wireless networks powered remarkable economic growth and transformed the
way Americans live and work. The study shows the powerful impact of wireless on
the economy as American providers begin to rollout next-generation 5G networks,
which will create a new 5G economy over the next decade. The report's key findings
include that nearly 10% of the GDP increase of the entire U.S. economy from 2011
to 2019 was due to the growth of the U.S. wireless industry, and that U.S. 4G networks
support 20 million jobs, drove nearly $700 billion in economic contribution last
year alone, and save consumers $130 billion each year..."
Join Altum RF, a supplier of high performance
RF to millimeter-wave semiconductor solutions for next generation markets and applications,
IMS2020 Virtual Conference. Altum RF will showcase its featured products and
technical expertise in its virtual booth. Company leaders will be online to answer
questions about specific products, future plans and their decades of expertise designing
and delivering RF, microwave and millimeter-wave semiconductors. New products featured
in the booth include the ARF1307C7, a 1-20 GHz GaN distributed amplifier that
delivers 10 W of saturated output power, and the ARF1010Q4, a 20-30 GHz
1 Watt amplifier for 5G millimeter-wave infrastructure and 24 GHz ISM
If you think electric cars are a new idea,
read on. I saw this article, "The Amazing
Collection in Thomas Edison's Garage," on another website (the equivalent of
Jay Leno's Garage from a century ago) and thought it was a special report,
but then I noticed it was actually a paid promotion. So, I contacted the company,
B.R. Howard & Associates, Inc., asking for permission to re-post it in its entirety
on RF Cafe. They kindly agreed to it. Per their mission statement: "Our company
focuses on the conservation of historic artifacts in accordance with the principles
defined in the American Institute for Conservation of Historic and Artistic Works
Code of Ethics and Guidelines for Practice." Their portfolio of projects include
transportation, industrial, scientific, military, and archeological artifacts. An
opportunity to help support the preservation effort is provided...
Artech House today announced the release
of Artech House today announced the release
Deep Learning for Radar and Communications Automatic Target Recognition
by U. Majumder, E. Blasch and D. This exciting resource identifies technical
challenges, benefits, and directions of Deep Learning (DL) based object classification
using radar data (i.e., Synthetic Aperture Radar/SAR and High range resolution Radar
/ HRR data). An overview of machine learning (ML) theory to include a history, background
primer, and example and performance of ML algorithm (i.e., DL method) on video imagery
is provided. Radar data with issues of collection, application, and examples for
SAR/HRR data and communication signals analysis is also discussed. Practical considerations
of deploying such techniques, including performance evaluation, hardware issues,
and the future unresolved issues are presented. Special intro price available
for a short time.
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.
After reading so many articles about vintage
vacuum tube radios and TVs in the older electronics magazines, it makes me appreciate
the relatively trouble-free products we enjoy today thanks to semiconductor technology.
Monthly columns were filled with troubleshooting advice and tips for making modifications
to factory designs that will enhance performance and/or reduce the likelihood of
premature failure. Although many tubes did outlast the lifetime of the chassis in
which they were installed, it was pretty much a given expectation that sooner or
tubes would need to be replaced - that is why they were the only components
that came installed in sockets for easy removal and installation. Fortunately, because
of the huge volumes produced, prices were relatively low, and many stores - not
just electronics shops - had self-serve...
technical panache, one of The Aerospace Corporation's CubeSats maneuvered itself
within 22 meters of its sibling CubeSat and snapped a series of photos while orbiting
at 17,000 miles per hour. This incredibly difficult technology demonstration, performed
by a satellite the size of a tissue box, paves the way for future inspection or
servicing missions. 'AeroCube-10
is by far the smallest spacecraft to have accomplished a rendezvous and proximity
operation so close,' said Catherine Venturini, an Aerospace Senior Project Leader
and team lead..."
RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 13,000 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. Advertising begins at $40/month.
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms are
available to provide temperatures between −100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
Most Ham radio operators know that Franklin
D. Roosevelt issued an order during World War II that effectively suspended
the hobby of amateur radio for the duration of the war. Many guys sold or donated
equipment to the military and/or civil defense organizations out of a sense of patriotism.
Radio Corporation of America (RCA) gave a symbolic tip of the hat to them in
this advertisement that I scanned from the back cover of my copy of the April 1945
QST magazine. Of course RCA pitched the ruggedness of its vacuum tubes
in the process. By this edition's printing, there was a general sense that the war
was nearing an end and eager Hams would not have to wait much longer to re-engage
in their beloved hobby. Indeed, the next month Germany surrendered and four months
after that Japan surrendered. WWII was over at long last...
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.
August 2nd's custom
Communications Engineering crossword puzzle contains some words particular to
radio, radar, analog and digital circuits, components, and other tech-themed words
and clues. Each week for two decades I have created a new technology-themed crossword
puzzle using only words (1,000s of them) from my custom-created lexicon related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will
never find among the words names of politicians, mountain ranges, exotic foods or
plants, movie stars, or anything of the sort. You might, however, find someone or
something in the otherwise excluded list directly related to this puzzle's technology
theme, such as Hedy Lamarr or the Bikini Atoll, respectively...