|
 The debate about upgrading electronics service
shop equipment
from vacuum tube to solid-state instruments was raging in the late 1960s, when
this Mac's Service Shop story appeared in Electronics World magazine. Barney
is querying Mac regarding FET-based VOM performance specifications he is considering
to replace a VTVM. He covets the Hewlett-Packard 217A square-wave generator, delivering
clean 1 Hz-10 MHz waves with 5-ns rise time and scope triggering, justifying its
$300-$400 cost for precise scope testing. An electronic counter for 5 Hz-10 MHz
frequencies, with four- or six-digit readouts and line- or crystal-gated accuracy..
 A lot of people like to demean engineers and
scientists for their propensity to want to
conduct experiments and obtain measured, empirical data rather
than "winging it" and being satisfied with "intuitive" knowledge or the contemporarily
popular term "gut." If mankind had not adopted scientific methods and ventured beyond
the "cradle of civilization" on the African continent, we would all still be living
in grass huts, hurling rocks at prey, making clicking sounds for communication, and foraging for berries. Quantifying and
categorizing all things in nature helps inventors create new and improved implements
that help make life better. Early on it was mostly individuals like Archimedes,
Euler, Newton, and Edison who built the pool of knowledge that fed and evolved
into corporations, governments, and universities doing the vast majority of the
work. Bell Laboratories...
 "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..."
 You can buy a pretty good metal detector
today for a hundred dollars that will find coins buried many inches deep and larger
metallic items even deeper, and you even get discriminator functions to filter out
unwanted objects like tin cans. They weigh just a couple pounds and can be used
with one arm. Compare that to early
metal detectors that had huge induction coils on a frame so heavy
that shoulder straps were needed just to lug them around. Some models came on wheels
for pushing or pulling like a cart. You could plan to spend a few hundred dollars
(a thousand or more in today's dollars) for one. Even then, they were not as sophisticated
as the $50 models sold in Walmart now. In classic fashion, teen electronics hobbyists
Carl and Jerry use their technical prowess to design and build their own metal detector
and then unintentionally using it to convince...
 This might be one of the earliest printed
instances of Harold A. Wheeler's simplified formulas for the
three basic inductor forms. Wheeler is credited with having devised the first
automatic volume control (AVC) using diode envelope detection. We all use them on
a regular basis, but for most the origin was never known or has long since been
forgotten (I fall into the latter category). I did some research on Wheeler's
inductance formulas a few months ago while working on what is now titled "RF Cafe
Espresso Engineering Workbook™," so it was sort of déjà vu when this blurb appeared
in a 1932 edition of Radio-Craft magazine...
 The leading website for the PCB industry.
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.
 Don't let the title fool you. This "Ultrafax" system developed by RCA in the late 1940s was essentially
the first attempt at video on demand, or streaming video. Rather than piping the
signal over cable or local broadcast frequency towers, a microwave link was used.
While initial system equipment space and financial requirements meant only corporations,
universities, and governments could procure an Ultrafax, engineers who developed
the system envisioned an eventual culmination of equivalent systems in every home.
Even at the end of the last century it was still not possible for program providers
to personalize broadcasts to individuals. It wasn't until broadband Internet came
on the scene in the 2000s that such services were possible. Now, a decade later,
people watch any video they want on cellphones while riding in a car...
 Maxwell's inception of the theory of electromagnetic
radiation is compared here to if Christopher Columbus had conceptualized the existence
of America and mapped its features based solely on observations of how the known
oceans and land masses interacted. I have always been amazed at the ability of people
who formulate entirely new theories of science, finance, medicine, etc., and manage
to detail and support their ideas with hard data and mathematics. Einstein did so
with relativity, Dalton did so with atomic structure, Darwin did so with evolution,
Pasteur did so with germ theory; the list is long. There are lots of geniuses out
there, but a relative few change the world...
 "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)..."
 Werbel Microwave began as a consulting firm,
specializing in RF components design, with the ability to rapidly spin low volume
prototypes. Our
WM4PD-0.5-18-S is a wideband 4-way in-line power splitter covering 500 MHz
to 18 GHz with excellent return loss, low insertion loss, and high isolation
performance. The device covers several military radios letter octave bands in one
product, delivering much value to the program. Aluminum enclosure measures 6.25
x 2.98 x 0.50", includes four through-mounting holes, and has durable, stainless
steel SMA female connectors. One device covers the upper UHF band, as well as L,
S, C, X and Ku bands...
 This week's
Wireless Engineering crossword puzzle contains the usual collection
of 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!
 Providing full solution service is our motto,
not just selling goods. RF &
Connector Technology has persistently pursued a management policy stressing
quality assurance system and technological advancement. From your very first contact,
you will be supported by competent RF specialists; all of them have several years
of field experience in this industry allowing them to suggest a fundamental solution
and troubleshooting approach. Coaxial RF connectors, cable assemblies, antennas,
terminations, attenuators, couplers, dividers, and more. Practically, we put priority
on process inspection at each step of workflow as well as during final inspection
in order to actualize "Zero Defects."
 "Essayons," that's the motto of the U.S.
Army Corps of Engineers. It means "Let us try," in French. In 1968, when this
G.I. Engineers editorial appeared in Electronics World magazine, it
noted that about 38,000 engineers, or roughly roughly 6% of the nation's total,
served in the U.S. Armed Forces, far more technically skilled than in World War
II or Korea. Despite surpluses in bachelor's-degree holders, advanced-degree shortages
persisted, with over 15 thousand master's and PhD positions unfilled - by fewer
than 8,500 qualified personnel, forcing underqualified assignments. Utilization
varied: Air Force effectively deployed 14,000 engineers in R&D and civil roles;
Navy specialist programs covered ship, ordnance, aeronautical, and Civil Engineer
Corps (Seabees)...
 Here is a handy-dandy baker's dozen worth
of "kinks," otherwise known as
tricks, shortcuts, or clever ideas, that could prove useful while
working in the lab at work or in your shop at home. One suggestion is to place a
sheet of tracing paper over your schematic while wiring a circuit and draw each
connection as it is completed, rather than mark up the original drawing. That was
definitely good for a time when making a spare copy of a magazine page or assembly
instruction from a kit was not as simple a matter as it is today...
 "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..."
 This week's
crossword puzzle has the theme of electronics and engineering
magazines and their editors. I have to plead guilty at not knowing who the editor-in-chief
(EiC) of many of the publications were. After so often reading the names of the
many authors and technical editors and contributing editors, etc., getting printed
every month, keeping track is difficult. You should recognize all the magazine names
since they are our industry's primary publications. Apologies to Microwaves &
RF magazine (Nancy K. Friedrich, EiC), and to High Frequency Electronics
(Scott Spencer, EiC), for not including them in the puzzle. The fact is, though,
that the more words I insert at the outset, the more difficult it is...
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus'
AMP20097 Pulse Amplifier is designed for Pulse/HIRF, EMC/EMI Mil-Std 461/464,
and radar applications. Providing superb pulse fidelity and up to 100 μsec
pulse widths to 10 kW peak power. Duty cycles to 10% with a minimum gain of
63 dB. Available monitoring parameters for forward and reflected power in watts
and dBm, VSWR, voltage, current, and temperature sensing for outstanding reliability
and ruggedness in a compact 7U chassis...
 If you have been searching for a do-it-yourself
VLF loop antenna that can be resonated from approximately 14 to
25 kHz, then look no more. This article from a 1963 edition of Electronics
World presents a relatively simple to build job that reportedly provides excellent
reception. At these frequencies a wavelength is measured in miles, which makes even
a simple dipole antenna impractical, so the multi-turn loop is the only alternative.
It is the same principle that allows the little ferrite-core antenna inside your
AM radio to work so well when the shortest wavelength in the commercial AM broadcast
band is nearly 600 feet...
 This 1968 Electronics World magazine
article nails the basics of
trade secrets law that still hold today: if you learn your boss's secret info
- like formulas, processes, or customer lists that give them a business edge - you
can't share it with a new job, even by accident, and your new employer can get sued
if they know about it and use it. No signed paper needed; courts protect "real"
secrets (not public stuff or your general skills) with court orders to stop use
or money damages. Good faith matters - act fair, don’t copy files or exact products,
and you have defenses like competing honestly. Big changes now: almost all states
follow uniform rules (UTSA) plus a 2016 federal...
 Here is a batch of
electronics-themed comics that appeared in the July 1948 edition of Radio
News magazine. The comic on page 122 would probably elicit cries of racism
or hate speech these days, even though there is nothing racist about it. Note how
prescient the comic on page 140 was. It shows how long futurists have ben contemplating
the technologies that have become or are becoming common place today - of course
many of them were promised to us by the end of the last century by the like of
Popular Mechanics, Mechanix Illustrated, et al...
 "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..."
 If you think government bureaucracies meddling
in the affairs of private business is a relatively new phenomenon, think again.
Elected and unelected persons and agencies have since the inception of control over
the populace made it their business to dictate which pursuits of technology are
sanctioned and which are not. Often, the motivation lies in who within those bureaucracies
stands to benefit monetarily from the decision. In this story lamenting the painfully
and, in the author's opinion, unnecessarily long time experienced in bringing
commercial broadcast television to the marketplace - in 1935.
One of the primary stumbling blocks was the FCC preventing companies from televising
paid commercials during programs because, in the FCC's view, picture quality was
not good enough to serve advertisers' interests. In this story lamenting the painfully...
 Here in one short editorial article, Hugo
Gernsback outlines the application of
shortwaves in "the next war" to maintain wireless surveillance of the airspace
over towns and cities via what is essentially radar, to detonate explosive devices
by means of a powerful "special combination impulse," and long-distance wireless
communications via radios "so small that one man can easily carry it." This might
seem rather moot in today's world, but in 1935 it required a certain amount of knowledge
of wireless communications and a vision regarding its potential. In my readings
of a great many early- to mid-20th-century technical articles on electronics, aeronautics,
physics, etc., it is interesting to notice how authors of the pre-WWII era referred...
 Here is a layman's analysis of the Lorentz
force, a fundamental principle in electromagnetism governing the interaction of
charged particles with electric and magnetic fields. Named after Hendrik Lorentz,
the force law underpins numerous engineering systems from electric motors to particle
accelerators. The document details Lorentz's biography, the discovery context, precise
definition, mathematical derivation, equations, and both historical and contemporary
applications. Hendrik Antoon Lorentz (1853-1928) was a Dutch physicist whose contributions
to theoretical physics...
 In 1938, Bell Telephone Laboratories, Western
Electric Company, United Air Lines, and Boeing worked together to developed the
first practical
microwave radio altimeter for use in commercial aircraft. This
is not a radar unit in that the distance is not determined solely by emitting a
signal and measuring the time taken to the target (the ground in this case) and
back again. Rather, the radio altimeter relies on a heterodyned beat frequency generated
between a reference signal and that of the transmitted and received ground-directed
signal. Author Washburn does a nice job explaining the process, so I needn't add
to it. It is interesting to note the statement about the 500 MHz used being
the "highest frequency ever to be used for practical purposes...
 "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..."
|
 • India Reaches
400M 5G Subscribers
in 3 Years
• EIB Backs
Europe's 1st Gallium Production Investment
• 2026 a
Pivotal Year for 6G Standardization
• New
60-Meter Frequencies for Hams
• EMC
Test Lab Market Expected to Double in 10 Years
 The
RF Cafe Homepage Archive
is a comprehensive collection of every item appearing daily on this website since
2008 - and many from earlier years. Many thousands of pages of unique content have
been added since then.
 A while back I was using the familiar
analogy that relates water pressure, hose diameter, and flow rate to electrical
voltage, resistance, and current, respectively, in an explanation to my daughter
regarding why the water characteristics in her house changed after the well supply
pipe and indoor plumbing changed. The cause, I proposed, was due to an increased
distance between well and house, and the use of the plastic PEX tubing with a smaller
inside diameter than the old copper pipe, respectively. The submersible pump and
holding tank still supply the same 50 psi as before, but since that pressure
now has to force the water through a path inside the house with more resistance
to water flow, the delivery rate to fixtures is now lower. When I hold the contacts
closed on the pump control relay, the most I can get is about 55 psi. Raising
the pressure will require replacing...
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed crossword puzzle using only words 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,
see someone or something in the exclusion list who or that is directly related to
this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy...
 Multiple path transmission, diffraction around
obstacles, absorption by foliage, and reflection from moving objects have always
been challenges to the wireless system designer and/or user. Whether it concerns
communications between a WiFi router and a notebook computer, a cellphone and a
tower, an FM radio with a broadcast station, or deep space probe with an earth station,
all of the aforementioned mechanisms must be dealt with to some degree. Although
in a different way, even
transmissions within a waveguide or coaxial cable deal with those same issues
- reflections and the resulting standing waves have the same effect as multipath
in terms of vectorially additive versions of the same original signal. Signal degradation
issues can usually be overcome when all components are performing within specifications,
by having knowledge potential causes, and then assessing the situation at hand.
Of course an insufficient signal power from the transmitter, too-high Friis-determined
atmospheric path loss, and inadequate receiver sensitivity under ideal conditions...
 Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 225,000 times per year! 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. If you need your company
news to be seen, RF Cafe is the place to be...
 James Kilton Clapp in 1948 first published
details on an oscillator that used positive feedback obtained from an LC (capacitive &
inductive) voltage divider to initiate and sustain oscillations. Thus was born the
now familiar Clapp oscillator. It had an advantage over both the Colpitts and Hartley
oscillators because the feedback, not being dependent on a simple capacitive or
inductive voltage division, respectively, made it more reliable as a variable frequency
oscillator (VFO). This article does a nice job of explaining the operation of the
Clapp oscillator. Just as the Colpitts and Hartley oscillators handily provide an
easy mnemonic for being based on voltage dividers of capacitance with the Colpitts
oscillator and inductance (Henries) with the Hartley oscillator, the Clapp oscillator...
 Carl and Jerry were early adopters of the
near field communications (NFC) craze that is going full-swing today. As they often
do, the harmlessly mischievous teenage duo used their combined grasp of modern electronics
to pull off gags on unsuspecting friends ... and sometime adversaries. In this episode,
a near-field transmitter and receiver pair is designed to help Carl bedazzle a scientist
who was attempting to disprove the ability to use "Extrasensory Perception" (ESP)
- the title of this 1956 Popular Electronics magazine technodrama - to determining
what another person was thinking about. In this case it was detecting which playing
card was being displayed on an overhead projector. Of course Carl didn't really
have "the gift," but relied on his co-conspirator, Jerry...
 Research has shown over and over again that
engaging in mental exercise is a good way to stave off senility in old age. Playing
musical instruments, writing software, working crossword puzzles, and other types
of activities that require logic, physical dexterity, and memory recall are often
cited as examples. There is no guarantee these things will prevent or even delay
cerebral atrophy, but why take a chance? Work this crossword just to make sure.
Disclaimer: I am not a doctor and am not prescribing this challenge as a remedy
for potential future imbecility, daftness, tendency to dodder, mental infirmness,
or senescent gray matter accumulation, nor do I suggest that starting now will reverse
any of these symptoms you might already exhibit. This
electronics-themed crossword puzzle appeared in the April 1963 issue of
Electronics World magazine. If you really like crossword puzzles and crave
more, please see my weekly RF Cafe crossword puzzles...
 If you look up "bit" on Wikipedia, is claims
the word is a portmanteau of binary + digit, but according to the "Electronic
Counter Tube" article in the March 1956 issue of Radio-Electronics
magazine, it comes from binary + unit. The cited reference is a 1980 book. That's
a minor point, but I wonder if the belief has changed over time. Going further down
the metaphorical rabbit hole, per the same source, "The term byte was coined by
Werner Buchholz in June 1956, during the early design phase for the IBM Stretch
computer." Now, back to the topic at hand. The E1T "Decade Counter Tube" was produced
by Mullard, located in the UK. It had an ingenious design which directed an internal
electron beam onto fluorescent numerical segments according to the number of pulses
supplied to the increment grid (D1 in Fig. 1). A holding voltage...
 If I have ever heard of a "trigistor"
(aka "dynaquad") before seeing it in the 1960 Radio-Electronics magazine article,
I don't remember it. It is a p-n-p-n silicon switch device that is essentially the
same as a thyristor in that conduction can be turned on or off with separate control
signals that can be removed once the switching action is initiated. According to
the Wikipedia entry for the thyristor, it was first introduced in 1956, not so long
before this article. The Howard W. Sams Transistor Circuit Manual, 1961, by
Allan Lytel provides information on not just the "trigistor," but also the "binistor,"
another bistable on/off silicon switch. Other process control devices such as unijunction
transistors, avalanche diodes, silicon controlled rectifiers (SCRs), and cryostats
(used for temperature control) are discussed. The electronics industry was in the
early stage of transition from vacuum tubes to solid state devices...
 A month prior to this
Metal Lens news item appearing in Radio-Craft magazine (May 1946),
the inventor, Bell Telephone Laboratories, ran a full-page advertisement boasting
of their accomplishment. As mentioned in my write-up, it is sort of akin to the
Osgood optical lens used in lighthouses. Imagine performing the mathematical calculations
required to design that thing using a slide rule! Also reported here was the resumption
of regular television broadcasting in England by the BBC after war-caused alterations
in programming. Compared to the capability, compactness, and weight of modern night
vision equipment available today (see examples on Amazon for <$200), the "Snooperscope"
presented here is a very crude device. It relies on a powerful infrared light source...
 This might be one of the first advertisements
for
Rohde & Schwarz (R&S) test and measurement (T&M) products
to appear in a U.S. publication (December 13, 1965 Electronics). A brief
search for earlier instances did not turn up anything prior to 1965. Please contact
me if you have seen one. R&S, as you probably know already, is now a major player
in the communications T&M world. Hewlett Packard (HP) of course was one of the
largest - if not the largest - maker of spectrum analyzers, network analyzers,
noise figure test sets, modulation generators and analyzers, signal generators,
o-scopes, etc., up through about the 1980s - maybe into the 1990s. Once the cellular
and wireless everything markets took off, Rohde & Schwartz test equipment (TE)
began...
 Just as with modern day wireless and cellular
network build-outs, the phenomenal costs involved in planning, implementing, maintaining,
upgrading, and expanding coverage for wired networks of yore (as well as what remains
of today's) was/is paid for by paying subscribers. Per this 1948 Radio News
magazine article, American Telephone and Telegraph (AT&T) company's investment
in network service at the time was well over $20,000,000, and that nearly a dozen
basic networks regularly used 90,000 miles of wire. The included photo of the stripped
end of a lead-sheathed multi-conductor cable is an indication of how complex and
massive the effort was. A lot of engineering hours went into developing just the
cables, let alone the citing and building of support towers, burial paths, relay
and switching stations (and getting AC power to them), lightning protection, personnel
and equipment access, and so much more. Aside from the lawsuits and court rulings
regarding monopolistic and anticompetitive practices...
 Ever the enthusiastic futurist, Radio-Electronics
magazine editor Hugh Gernsback laid out the need for and predicted the implementation
of an electronically broadcast form of newspaper publishing. He states, "In this
electronic-automation age, physical newspapers, that must be printed at a central
plant, then distributed by trucks to newsstands, or mailed or transported by rail
or air to distant cities, are an anachronism. They are wholly unnecessary and economically
suicidal." That was in 1963, when he discussed the technology "RAFAR" (from
Radio Automated Facsimile And Reproduction). Facsimile (fax) machines were already
in use with signals being transferred over telephone lines. My first question was
how is the entire newspaper content made available on demand by multiple users?
There was no means of electronically storing that much information other than on
magnetic tape. The RAFAR scheme had a miniature version of the newspaper printed
on paper, then the reader scrolled through the paper while viewing a magnified image
projected on a glass screen - akin to a microfiche machine. Magnetic storage could
have been used...
 Since I am currently planning a loudspeaker configuration
to replace the original speaker in my 1941 Crosley 03CB floor model AM / shortwave radio
set, this article made for a good refresh on
audio frequency crossover networks. A very nice set of design charts is provided.
Of course today there is no need to design and build your own since commercial units
are very good and cost less than what I could build myself. Many moons ago while serving
in the USAF at Robins AFB, Georgia, I did actually build my own crossover circuit for
use in custom speaker cabinets I built in the base woodshop. The speaker that came in
the Crosley has a 12" cone, which is still in good condition, but it uses an electromagnetic
voice coil rather than a permanent magnet like modern speakers use...
 As usual, "getting" the message in some
of these vintage
electronics-themed comics requires at least a passing familiarity with the state
of technology and public mindset of the day. However, in most cases appreciating
the humor and/or irony is possible without it. This group of six comics appeared
in a 1953 issue of Radio-Electronics magazine. The first comic is a good example
of needing some insider information. Back when commercial television was broadcast
over the air from giant towers, multipath of the signal, particularly in urban areas,
often created a situation where the difference in arrival time of the signal at
the TV viewer's location caused more than one version of the picture to be displayed,
slightly offset from each other...
 Most people today under 30 years old have
probably never seen the mechanics or electronics inside their many personal devices.
Everything is so miniaturized and optimized that if something does go wrong, there
is little chance of the owner repairing it. Instead, the phone, television, stereo,
microwave oven, whatever, gets thrown away and a relatively cheap (compared to paying
for a repair) replacement is purchased (or stolen). Besides, if the item was more
than two years old, it was on the verge of obsolescence anyway. Up until around
the early to mid 1980s you had a fair chance of being able to repair an electronic
circuit if trouble arose because at least with commercial products
printed circuit boards (PCBs) were usually 1- or 2-sided and the components
still had leads protruding from the sides of the packages. A $10 Radio Shack soldering
iron and some solder wick was sufficient to remove and replace just about any failed
component. Home brew PCBs could be made to nearly the same quality as commercial
versions using a resist ink pen (basically a Magic Marker) and a dish of ferric
chloride etchant liquid. A drill press helped with making holes for the component
leads, but a hand drill would get the job done. No more, though. If you are resourceful
enough to get your cellphone...
 Most of us have heard about the neighborhood
collections for tires, glass, newspaper, cans, and cloth in order to help support
the war effort. Probably not many have also heard about the Signal Corps'
call for milliammeters! That's right, the huge, rapid build-up of electrical
and electronic equipment for radios, vehicles, and factory equipment. Many meters
were needed for monitoring status and making process adjustments. America had an
ample supply of meters in the hands of Amateur radio operators; all that was required
was to separate the Hams from their meters. Fortunately, an appeal to patriotism
was sufficient motivation back then. Numerous ads were placed by companies and special
interest groups like the ARRL encouraging milliammeters owners to part with their
cherished instruments. Here, from the November 1942 edition of QST magazine,
is a printed plea from the ARRL, and a couple examples of companies looking to collect
milliammeters...
 Unlike the last two decades where people
like me have been making it available, procuring
service information on commercial products could be very time consuming, and
often resulted in not even obtaining what was needed. Thanks to the Internet now
being populated with schematics and mechanical drawings for seemingly everything
ever made, we no longer need to call or mail order for information needed to repair
your radio, television, cellphone, lawn mower, toaster, or anything else. Granted,
most people these days toss out broken items and just buy new ones. Before the advent
of companies like Sam's Technical Publishing information packets, it was often impossible
to obtain schematics and service information from manufacturers unless you were
a certified service shop and/or dealership. In response to many inquiries from
Radio-Craft magazine's readers, publisher Hugo Gernsback queried the top
manufacturers of the day to determine their policies for distributing such data... |
