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Friday the 6th
Thursday the 5th
Wednesday the 4th
Tuesday the 3rd
 For decades - literally - I searched in
vain for explicit , but could never find more equations
for calculating Chebyshev filter phase and group delay than textbook
definitions, with instruction to extract phase from the real and imaginary parts
of the magnitude equation, and then take the negative first derivative of the
phase to get group delay. A lot of good that did - not! I have perused dozens of
filter design books, to no avail. Even the filter bible - Zverev's Handbook of
Filter Synthesis - did not provide the needed equations. Most online resources
present Mathcad, MATLAB, Mathematica, or similar scripts that call the built-in
functions, without exposing the gory detail behind them. What I wanted was
something I could implement in a spreadsheet or a program. Finally, with the
help of AI (through many iterations of...
 News services have been busy lately reporting
on the latest feat of America's national space agency's resounding success with
its interplanetary space probe's closest encounter with our solar
system's most remote [minor] planet. Prior to the flyby, even the most powerful
Earth- and space-based telescopes could never resolve more than a few lightly contrasted
splotches on the celestial orb's surface, and its largest moon was a few pixels
worth of indeterminate light. All that changed on July 14, 2015. We now have, for
the first time ever, high resolution images of the surface, and are in the process
of collection terabits worth of additional physical data from onboard instruments.
No doubt many Ph.D.'s will be earned through assimilation...
 Amplifier
Solutions Corporation (ASC) is a manufacturer of amplifiers for commercial &
military markets. 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. ASC
is located in an 8,000 sq.ft. facility in the town of Telford, PA. We offer excellent
customer support and take pride in the ability to quickly react to evolving system
design requirements.
Monday the 2nd
 In the late 1960s, there was evidently a
brewing consumer revolt against
shoddy merchandise, worthless warranties, and sloppy service. Mac attributed
this to a post-WWII seller's market fueled by wartime shortages, black markets,
and inflation. Many workers had pent-up money to spend on products not readily available
during the war. Ensuing conflict eras like Korea and Vietnam prioritized volume
production and advertising over quality. Demand escalated prices. Customers, once
kings in a competitive free-enterprise system, became expendable amid abundant demand.
By 1969, when this story appeared in Electronics World magazine...
 Here are three
electronics-themed comics from vintage issues of Electronics World
and Popular Electronics magazines. My favorite is the page 84 comic where
the sign on the Telco Rectifier Components president's wall is apropos. Maybe one
of the interview questions for job applicants was #1: "Did you notice the sign on
the wall in the waiting room," and #2: "Did you 'get it?,' and please explain."
In 1956 when that comic appeared, AC-to-DC power supplies used high voltage vacuum
tubes, typically 300 volts or more. Hefty capacitors were needed to remove
enough ripple from the "top" of the DC to render it undetectable in the circuit
output - especially if the output was audio where a 60 or 120 Hz (50 or 100 Hz
in Europe) "hum"...
 "Future lunar missions face a fundamental
challenge: the high cost and difficult transport of materials from Earth. Now, a
new project supported by the European Space Agency (ESA) will demonstrate how lunar
soil -- after releasing its oxygen for rocket propulsion and potentially air for
astronauts -- can also be converted into metal-rich compounds which can conduct
electricity. This compound can either be transformed to inks for
printing electronic circuits or powder for 3D printing of larger components.
Danish Technological Institute..."
A mathematics professor explained to students through various lectures and examples:
It became obvious not everyone understood after one student submitted the following
on a pop quiz:
- originator unknown.
 It seemed weird to read of
microelectronics device density expressed in parts per cubic foot
of semiconductor substrate. Describing density that way makes some sense when considering
3-dimensional devices with vertically stacked elements, but this was in a 1963 article
in Electronics World, so that could not have been the case. The motivation, evidently
was to be able to compare microcircuit density with that of the human brain in terms
of neuron density. In fact, there is an interesting chart presented that shows the
evolution in circuit density beginning with vacuum tube circuits, progressing through
the state of the art in 1963, projecting for future years, and finally peaking with
the brain's density. Interestingly, the brain density shows as about 5x1011/ft3,
while the "nonredundant semiconductor device" limit is...
 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.
Sunday the 1st
 Breaking News!
Espresso Engineering Workbook™ v2.2.2026 has just been released. This makes
the 49th worksheet added. It calculates magnitude, phase, and group delay for Chebyshev
Type 1 lowpass, highpass, bandpass, and bandstop filters. Outside of the kilobuck
simulators, finding a calculator for phase and group delay is extremely difficult
- believe me, I've searched extensively for years. It also has a Butterworth filter
for the same. Espresso Engineering Workbook™ can be downloaded free of charge. All
you need is Excel™ v2007 or newer. It is provided compliments of my advertisers.
Contact me if you would like your company added to the next release.
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 As the advertisement for membership in the
Official Radio Service Men's Association says, structured organizations
for people of like mind and interests have long been the hallmark of an advanced
society where there is a need for directed socialization and the 'strength in numbers'
benefit. I suppose most people reading this piece belong to at least one such association
like the Institute for Electrical and Electronics Engineers (IEEE), American Radio
Relay League (ARRL), Armed Forces Communications and Electronics Association (AFCEA),
Association of Old Crows (AOC), Electronics Technicians Association (ETA), etc.
Having significant representation in government in the form of lobbyists is essential
these days in order to obtain and retain fair treatment...
 Repair service businesses have always gotten
a bad rap for deliberately inflating part and labor costs - often deservingly so
- but it's a shame the honest brokers are dragged down by the scum (or "gyps" as
this article calls them). Come to think of it, the word "gyp" is likely short for
"gypsy," which is sure to offend someone these days. Along with admonishing customers
to beware of shyster servicemen, there is an example of an orchestrated
"sting" operation whereby a radio set was intentionally "broken"
in a certain way with witnesses as to the fault, and then a couple dozen repair
services were called upon to troubleshoot and fix it, then present a bill for their
work. The result is interesting, and even resulted in one guy being...
 This is an all-star cast of
radio pioneers if there ever was one. It's not comprehensive by
any means, but most of the first-string players are here in this 1936 Radio-Craft
article. One thing I like about reading these old pieces is that they, for the most
part, are reporting on contemporary events; they are not merely a historian's interpretation
of what the original witnesses recorded. That is not to say early writers did not
editorialize, err, or outright lie about content, but I give these guys the benefit
of the doubt based on the sources. You have certainly heard of people like Hertz,
deForest, and Marconi, but what about coherer (early detector) inventor Edouard
Branly and ground-breaking commercial radio broadcast engineer Frank Conrad? Magazine
editor, publisher, and inventor Hugo Gernsback properly give a short...
 I learned (or, "leared," in MN Somali daycare
lingo) a new word today -
ergodic - from a 1968 issue of Electronics World magazine. Ergodicity is a concept
from mathematics and physics describing systems where the time average of a property
equals its average across all possible states (space average). In simpler terms,
a system is ergodic if, over time, it explores all possible states in a way that
reflects the overall statistical distribution of those states. In physics and dynamical
systems: An ergodic system eventually visits all parts of its phase space...
 The use of
intermediate frequency (IF) coils
and interstage coupling transformers were a major feature of vacuum tube based receivers.
Both served the dual purpose of impedance matching and frequency selectivity. Resistive
losses in the relatively large passive components required careful attention to
matters that affect signal sensitivity, especially in the front end where losses
add significantly to the overall noise figure. This article appeared in an early
1930s edition of Radio-Craft magazine at a time when superheterodyne receivers
were just coming into popularity and were a new challenge for many designers...
2015 July - 2
 "Isolation dictates where we go to see into
the far reaches of the universe. The Atacama Desert of Chile, the summit of Mauna
Kea in Hawaii, the vast expanse of the Australian Outback -- these are where astronomers
and engineers have built the great observatories and radio telescopes of modern
times. The skies are usually clear, the air is arid, and the electronic din of civilization
is far away. It was to one of these places, in the high desert of New Mexico, that
a young astronomer named Jack Burns went to study radio jets and quasars far beyond
the Milky Way. Could there be a better, even lonelier place to put a
radio telescope? Sure,
a NASA planetary scientist named Wendell Mendell, told Burns: How about the moon..."
 "An international team of astronomers has
developed a new way to extract
solar polar magnetic information from more than a century of historical observations,
improving prospects for predicting future solar cycle activity. The work combines
data from the Kodaikanal Solar Observatory in India with modern measurements to
reconstruct the behavior of the Sun's polar magnetic field over more than 100 years.
Researchers from Southwest Research Institute, the Aryabhatta Research Institute
of Observational Sciences and the Max Planck Institute used archival Calcium K (Ca
II K) images..."
 "A UCLA-led, multi-institution research
team has discovered a metallic material with the
highest thermal conductivity measured among metals, challenging long-standing
assumptions about the limits of heat transport in metallic materials. Published
in Science, the study was led by Yongjie Hu, a professor of mechanical
and aerospace engineering at the UCLA Samueli School of Engineering. The team reported
that metallic theta-phase tantalum nitride conducts heat nearly three times more
efficiently than copper or silver, the best conventional heat-conducting metals..."
 "A new type of circuit board which is almost
entirely biodegradable could help reduce the environmental harms of electronic waste,
its inventors say. Researchers from the University of Glasgow have developed a new
method of printing
zinc-based electronic circuits on environmentally friendly surfaces including
paper and bioplastics. Once the circuits are no longer needed, 99% of their materials
can be disposed of safely through ordinary soil composting or by dissolving in widely
available chemicals like vinegar..."
 "A research team affiliated with UNIST has
introduced a novel, high-performance, and thermally stable polymer-based non-volatile
analog switch. This next-generation device is as
thin and flexible as vinyl, yet capable of withstanding high temperatures. Professor
Myungsoo Kim and his team from the Department of Electrical Engineering at UNIST,
in collaboration with Professor Minju Kim from Dankook University, have developed
this robust, flexible radio-frequency (RF) switch. Such technology could enable
reliable 5G and 6G wireless communication in demanding environments -- such as wearable
devices and the Internet of Things (IoT)..."
 "Apple has published a patent application
describing a method to detect user gestures on wireless earbuds by measuring changes
in RF antenna impedance, potentially reducing the need for dedicated touch-sensing
hardware. The filing, titled 'Gesture
Detection Based on Antenna Impedance Measurements,' published on January 8,
2026 as US 20260010234, describes using antennas already present for wireless communication
as dual-purpose components that can also detect user input..."
 "A new metasurface lets scientists flip
between ultra-stable light vortices, paving the way for tougher, smarter wireless
communication. Scientists have developed a new optical device capable of producing
two different types of vortex-shaped light patterns: electric and magnetic. These
unusual light structures, called
skyrmions, are known for their exceptional stability and resistance to interference.
Because they hold their shape so reliably, they are strong candidates for carrying
information in future wireless communication systems. 'Our device not only generates
more than one vortex pattern in free-space-propagating..."
 "Scientists have shown that
twisting a crystal at the nanoscale can turn it into a tiny, reversible diode,
hinting at a new era of shape-engineered electronics. Researchers at the RIKEN Center
for Emergent Matter Science, working with collaborators, have created a new technique
for building three-dimensional nanoscale devices directly from single crystals.
The approach uses a focused ion beam instrument to precisely carve materials at
extremely small scales. Using this method, the team shaped tiny helical structures
from a topological magnetic material made of cobalt, tin, and sulfur, known by its
chemical formula Co3Sn2S2..."
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