|
 February 1953 was just a little more than
four years since Messrs. Brattain, Shockley, and Bardeen announced their invention
of the transistor. This full-page advertisement by Raytheon ran in Radio-Electronics
magazine announcing the world's first commercially available
PNP germanium transistors. It was a big deal. Model numbers CK721
and CK722. CK721 handled about twice the collector current (12 mA) as the CK722,
both with collector voltages maxing out at around 8 volts. The introductory
price for the CK722 was $7.60, which in 2018 money is equivalent to $72.27* At that
cost, it is hard to believe they got anyone to replace vacuum tubes with transistors.
Fortunately, economy of scale rapidly brought prices down. Interestingly, CK722
inventor Norman Krim promoted a business...
 If you grew up in the era of rooftop television
antennas, then there is a good chance you are familiar with the electromechanical
antenna pointing systems that were often installed as well. Alliance, Channel Master,
Cornell Dubilier, Radio Shack, RCA, Winegard, and others made low cost, light-duty
rotators for television antennas. Ham radio antenna rotators were/are
more robust in order to handle higher weight and wind loads. Many television antennas
also cover the FM radio band (88-108 MHz), allowing them to do double duty.
Being an unapologetic technology renaissance man, I recently purchased (on eBay)
a vintage Alliance Model U-100 Tenna-Rotor that was unused in the original...
  Any time I see
an article that references causing limb movements by poking the brain with electrical
signals, I think of the old The Far Side comic. Artist Gary Larson drew quite
a few hilarious operating room scenarios.
Electrocution is of course not a laughing matter - unless it happens to someone else
and it is not serious and no harm is done. Then - and only then - can it be funny. I've
laughed at myself many times after receiving a good jolt due to stupidity. Sometimes
after such an experience I wonder how I never killed myself from getting zapped as the
result of being too lazy to turn off a circuit breaker before servicing a light switch
or receptacle. The sad thing is that I'll probably do it again some day...
 Pop Quiz: What is the contemporary name we have
given to the
voltage variable resistor (VDR)? Although VDRs are nowadays used most
familiarly for overvoltage protection due to spikes on a power or signal line,
they used to be functional parts of television display and power supply
circuits. They also made those newfangled field effect transistors - junction
(JFET), and enhancement mode and depletion mode insulated-gate (IGFET, aka
MOSFET). Thermistors, silicon-controlled rectifiers (SCRs), and varactor diodes
are also discussed. Sylvania was a prime user of all these devices back in the
day as part of their effort to modernize televisions and radio by abandoning
vacuum tubes wherever possible...
 Before there were side-view neon numerical indicator
vacuum tubes there were top-view neon
numerical
indicator vacuum tubes. Nixie tubes and pixie tubes were featured in "Readouts and
Counter Tubes" in the October 1959 issue of Electronics World magazine. At the
time, most were top-view designs whose size was restricted by the diameter of the tube
(typically about 0.8"). Switching to a side-view format did not enable the overall width
to increase much, but the aspect ratio permitted taller displays with characters that
appear as normally seen (rather than being squashed in height). This advertisement in
a 1965 issue of Electronics magazine for numerical indicator tubes from
Raytheon were likely some of the first side-view models available from any
manufacturer...
 Robert Balin created this
Electronic Factor Quiz for the November 1966 edition of Popular Electronics
magazine. Your challenge is to match the drawing of a particular electronics circuit
or implement with the corresponding "factor." Examples are "current amplification factor,"
"damping factor," "modulation factor," "duty factor," "form factor," "quality factor,"
etc. There are ten in all. Of course on a quiz like this you cannot get just one answer
wrong - or any odd number for that matter. I managed to reverse #5 and #10 (I and B,
respectively). For some reason I couldn't remember what "form factor" was, but was sure
that #10 was a scale factor of sorts... wrong - a clear case of cranial rectumitis...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (6/25 - 6/29)
"Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid
cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle
using only words from my custom-created 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...
 The
reflected-beam kinescope (RBK) held high hopes for large video displays with shallow
depths. A traditional cathode ray tube (CRT) is as deep from front to back as the width
of the display, which means, as anyone who has owned a CRT television or computer monitor
knows, a lot of space is required to accommodate a large display. Evidently the RBK never
panned out as a manufacturable product. Its "inside-out" configuration resulted in a
CRT that looks like someone reached through the front, grabbed the tail end, and pulled
it back through the front. In other 1960 news was a high voltage ferroelectric converter...
 Electrocution has always been - and always
should be - a hot topic (pun intended) in the realm of electrical and electronics
servicing and usage. Trade and hobby magazines have dedicated many column inches
to it over the years. A lot of people are deathly (there I go with the puns again)
afraid of being anywhere in the proximity of an exposed electrical connection. My
father, a newspaper classified advertising manager, was one of those people. He
would cringe when I took the cover off the fuse panel in the house to work on it.
He could barely bring himself to replace a blown fuse, which was not a completely
unjustified fear given the low standards of older electrical wiring. Those screw-in
fuses had a threaded metal perimeter around the bottom portion with a button connection
at the bottom center. Theoretically, that threaded metal perimeter is at ground
potential...
 "Xeledop" is the Word of the Day for October
31; use it often. Xeledop is an acronym for "transmitting elementary dipole with optional
polarity." Nope, I've never heard of it, either. The
Xeledop (probably pronounced "zeh'-le-dop") is an air-towed transmitter that
flies a pre-planned path around the ground-based antenna under test (AUT) whose
radiation pattern is being measured. The circular power level plot at the bottom
of the page shows the results of an actual test flight. In this application, a
high frequency (HF, 3-30 MHz) transmitter is towed behind an airplane like
target drone while it broadcasts signals at eight distinct frequencies toward
the AUT, while the downstream receiver records power levels. The pilot flies on
the surface of an imaginary hemisphere to maintain a constant radius from the
antenna. Ground equipment tracks the aircraft azimuth and slant range is
calculated using aircraft altimeter data and measured elevation angles...
 You just never know what names you will find
in vintage electronics magazines. Incredibly - assuming of course that this is who
 it likely is - I ran across
Steve Wozniak (aka "Woz"), later to be co-founder of Apple Computer,
in this November 1966 issue of Popular Electronics. "Woz" first met Steve
Jobs five years later in 1971 while working at Hewlett Packard. If this is "Woz,"
he, having been born in 1950, would have been a 16 year-old high schooler when his
entry was published. The article does not specify who is responsible for which quote.
Woz was a Ham radio..."
 This exercise would make a good laboratory experiment
for high school or junior college electronics courses. The required components are still
readily available - Borax is in the cleaners aisle of the grocery store. In the days
before vacuum tubes, when scientists had a need to
rectify alternating current power supplies they used chemical devices similar to
the one described here. Ironically, this chemical rectifier is a form of semiconductor
diode; albeit in a liquid state rather than in the eventual solid state. Note that the
rectifier symbol in the schematic is actually the chemical device created in the first
step - not a vacuum tube as it might appear to be...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (1/22 - 1/26)
"Tech Industry Headlines" column on the RF Cafe homepage (see the Headline Archives page
for help). For the sake of all the avid cruciverbalists amongst us, each week I create
a new technology-themed crossword puzzle using only words from my custom-created related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. Enjoy...
 It is probably safe to say that most people, especially
today, believe that the United States was suddenly and unexpectedly thrust into involvement
in
World War II on December 7, 1941, when the Japanese navy launched a
surprise attack on Pearl Harbor. The fact is the U.S. was "unofficially" engaged
for over a year beforehand by "lending" both equipment and personnel to British,
Russian, Chinese, French, and other militaries as part of their effort to drive
back invading German, Italian, and Japanese Axis forces. World War II actually
began in the Fall of1939 with Hitler's invasion of Poland. Americans, being
safely separated from the front lines by the Seven Seas, knew little of and were
concerned little about the goings on "Over There." Once the call to arms was
sounded with the Pearl Harbor attack, the country quickly and enthusiastically
converted to full wartime mode. Manufacturing plants...
 It's Friday and therefore time for a
pop quiz (does that line give you a fearsome flashback to your school
days?). Whenever I have one available, I like to post quizzes from vintage
electronics magazines, like this one on diode circuit functions. Many of them
have vacuum tubes, but this one has the solid state symbols so the under-40
folks won't be uncomfortable. Your job is to look at the diode circuits and
match them with the names of the functions. A couple of them will probably cause
some head scratching, but you should do well. Don't jump to a quick conclusion
with circuit "E" without noticing the two signal generators attached to it...
 In this saga of YL (young lady) and OM (old man)
Ham radio operators, General license holder
Carole H. Allen elucidates, with a touch of humor, the woes beset upon women
pertaining to repairing radio equipment. Mrs. Allen's lament is in fact not the
treatment of women participating in the communication aspect of Ham radio, but
the reluctance of men to allow them to engage in the technical aspects of the
electronic equipment. From an operator standpoint, guessing the gender of the
Ham on the other end of the signal can be nearly impossible, particularly with
CW (Morse code). Poor transmission quality can make phone (voice) determination
of YL or OM difficult sometimes as well. Back in the 1960s it was not possible
to simply surf to the FCC's Universal License System website...
 Are you old enough to remember when in order to
make a measurement on a circuit board it was necessary to physically connect an oscilloscope
probe to a trace or component lead? "Wait," you say, "What are you talking about? You
still do have to physically connect a probe." Right you are, but 50 years from now your
progeny will be asking that question, just as today I ask you do you remember when in
order to get a "screen shot" of an o-scope or spectrum analyzer display it was
necessary to
connect a camera to the front of the CRT? Some instruments had an(a) output
port(s) for driving a pen plotter, but getting a plotter set up and calibrated
was often more work and frustration than hanging a camera on the front. Most of
the cameras used Polaroid film packs to enable "instant" pictures...
 Just yesterday I posted an article titled "Understanding
Your Triggered Sweep Scope," that appeared in the May 1973 issue of Popular Electronics,
so I figured this "Scope-Trace
Quiz" would make a good compliment. It is from a 1965 issue of Popular Electronics.
Driver circuits all include a sinewave source in parallel with a series resistor and
diode, connected to the vertical and horizontal o-scope inputs. The resulting Lissajous
waveforms resemble hands on a clock face thanks to the diode. Shamefully, I only scored
70%, but in my own defense I'll say I didn't take the time to draw them out on paper.
Pay careful attention to the scope...
 By now, most people involved with spread spectrum
communications are (or should be) aware that Hollywood starlet
Hedy Lamarr is credited
for being the first to suggest a frequency hopping scheme for secure communications.
If you do a Google search on Hedy Lamarr and spread spectrum, you see that except for
a few mentions on tech websites, it has only been in the news since the end of the last
decade. Scientific American magazine ran an article titled, "Hedy Lamarr: Not
Just a Pretty Face," in 2008. Google honored her in 2015 with a Doodle on their homepage.
"The most beautiful woman in the world," with the assistance of her co-inventor-composer
George Antheil...
 Lightning season is upon us once again. The National
Weather Service says June, July, and August, are the most active lightning months in
the U.S., which is probably true in all of the northern hemisphere, and then December,
January, and February in the southern hemisphere. According to the National Safety Council,
the average American has a 1:114,195 chance of being
killed by lightning in a lifetime (which ends abruptly upon being
killed). That's much less than your chance of dying due to cancer (1:7) or being killed
in a car accident (1:102), but is sucks if you're that one in 114,195. Not all lightning
strikes are fatal, but many cause personal and property damage. Mitigating the chance
of being harmed requires taking some simple actions to not expose... |
 2001: A Space Odyssey, released in 1968
and based at least in part on Arthur C. Clarke's 1948 novel The Sentinel, was
more than just a science fiction movie. It was a reflection on the public's
and even some of the scientific community's trepidation over the potential power of run-amok
computers to be used for or even themselves commit evil (e.g, HAL 9000). Fear of
the unknown is nothing new. Noted
mathematicians and computer scientists quoted in this 1950 article from The Saturday
Evening Post worry about robots (aka computers) "going insane" or being
used by the likes of Hitler and Stalin to dominate the world with totalitarian
rule. Others, however, have a more optimistic outlook: "The men who build the
robots do not share these terrors. Far from destroying jobs, they testify, they
will create new ones by the hundreds of thousands...
 Here is an editorial excerpt from a 1965
issue of Electronics magazine that could be from a contemporary news publication:
"If U. S. manufacturers continue to abandon their engineering and production for
Japanese products, they are headed for oblivion because they cannot
compete with the purely merchandising organizations such as Sears, Roebuck &
Co. and Montgomery Ward* which buy Japanese products too." Of course you could easily
substitute South Korea, China, Taiwan, or any other now-prominent technology company
in place of Japan. American economic "experts" assured us in the 1990s that we no
longer needed to manufacture anything; rather, we would become a service and retail
economy. That worked out real well, eh?...
 A couple days ago I posted an update on the
Watkins-Johnson databook page that had an unauthorized gag graph titled, "WJ-G1/SMG1
Phase vs. VCTL vs. Frequency vs. Phase of the Moon." When RF Cafe visitor and sometimes
contributor Dr. Marek Klemes* read
that, he sent me a note about remembering this "Delayed
Light Turn-Off" circuit from the Signetics 555/556 Timer Databook. It took a
bit of creative Googling, but he managed to find the datasheet (to the right). The
text was a bit washed out from the original low resolution scan, so I reproduced
the labels (green). This Rube Goldberg-ish contraption works thusly: After a delay
determined by the values selected for R1 and C1, the output
of the NE555 timer goes high and causes resistor RL to heat up enough
to ignite match M1. M1 subsequently lights the fuse on firecracker
FC1, which has tied to its body a string that wraps around a pulley and
holds a rock (which weighs precisely 2π pounds...
 Here is a good, brief introduction to
harmonic and intermodulation distortion measurement methods that were
commonly used in the 1960s. Total harmonic distortion (THD) was used often,
especially for audio equipment, which of course most frequency conversion
circuits ultimately were in the era since digital data transmission over the air
was not too common. Author Charles Moore worked for Hewlett-Packard (HP) and
references HP Application Note 15, "Distortion and Intermodulation" which,
thankfully, is made available by Hewlett-Packard / Agilent / Keysight on their
website. In fact, a complete list of all the vintage app notes are available on
this page by downloading the Excel file. I highly recommend that you download
and save all you think...
 If you like word puzzles, then maybe you'll want
to give this
word search with names of common electronics components hidden within a matrix of
random letter a go. It appeared in a 1965 issue of Popular Electronics magazine.
Keep that in mind while searching for the Mystery Word. Enjoy...
 This is the electronics market prediction for
Belgium, circa 1966. It was part of a comprehensive assessment by the editors of
Electronics magazine of the state of commercial, military, and consumer
electronics at the end of 1965. Military systems for NATO and television sets
were a big part of the picture. Unless you can find a news story on the state of
the industry, detailed reports must be purchased from research companies. Their
websites have a lot of charts on Belgium's current electronics market showing
revenue in the consumer electronics segment amounts of US$1,295M in 2018...
 Note the byline in this 1953 Radio-Electronics
magazine article - Juliette Drut (she's on the cover). Not often were articles in electronics
trade magazines penned by a dame or damsel back in the day. For that matter, it's still
pretty rare today... hmmm... but I digress. If you thumb through any electronics magazines
from the middle of the last century, you find that the pages are filled with advertisements
offering courses to train prospects in the field of
television and radio repair, with promises of a potential to make big money.
Both institutional and home-study courses abounded. The costs never appeared,
but hey, with the money a fellow would be making soon, surely the price would be
inconsequential. Interestingly, in those same issues would be articles such as
this one addressing the reality of electronics servicing...
 1970 just doesn't seem all that long ago, but holy
moly that is going on half a century! This quiz appeared in Popular Electronics
to test the hobbyist's knowledge of the
whereabouts of some of the major components and products companies. Many of the businesses
have gone defunct, been bought and absorbed by other companies, or if they do still exist,
are in new locations. It will take a real old-timer to score well on this quiz without
resorting to lucky guesses. Still, there are a couple stalwart manufacturers today that
even a newcomer can get right. Most of the Popular Electronics quizzes were
created by Robert P. Balin, but this one was dreamed up by Thomas Haskett...
 If you are a fan of John T. Frye's "Mac's
Service Shop" series of technodramas, then you might also appreciate this short-run
stories by Bob Eldridge titled, "Another Day in the Shop." Up through maybe the early 1980s, every
town had at least one electronics service shop for taking care of televisions, radios,
record players, tape recorders and players, cameras, computers, and just about anything
else that might be fixed at less cost than buying a replacement unit. In the 1940's
through the 1960's, there was often good money to be made not only with in-shop
repair but also with doing house calls for repair and installation. Electronics
magazines of the era were filled with both self-help and tips for the professionals
regarding troubleshooting, use of test equipment, how to deal with customers, etc.
Electronics World even ran for a while a feature that suggested types and
quantities of replacement tubes, capacitors..."
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (1/29 -
2/2) "Tech Industry Headlines" column on the RF Cafe homepage (see the Headline
Archives page for help). A couple even include Super Bowl-related news. For the
sake of all the avid cruciverbalists amongst us, each week I create a new
technology-themed crossword puzzle using only words from my custom-created
related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. Enjoy!...
 Hugo Gernsback was well-known not just for
his technical prowess, but for an uncanny ability to predict future developments
in electronics, transportation, and production methods. Barely three years had passed
since Messrs. Bardeen, Shockley, and Brattain, announced their invention of the
transistor when this editorial titled, "Transistor Transition" appeared in Radio-Electronics
magazine. Gernsback mentions the concept of "appliqued circuits" (i.e., printed
circuits) and "roll-up display" transistor picture tubes (i.e., flexible displays),
and "pocket radios" that can be held up to the ear. Production prices for transistors
at the time were about $8 apiece, which is the inflation-adjusted equivalent of
$76 in 2018. At that price point, who could blame the pro-tube, never-transistor
crowd from denying the possibility of transistors ever replacing tubes...
 A lot of RF Cafe visitors might not be familiar
with some of the electronic devices presented in this
Electrochemistry Quiz by Popular Electronics' resident quizmaster, Robert
Balin (a big list of his other quizzes is at the bottom of the page). I offer my
assistance. A is a photocell, B is an early type of rectifier, C is a varistor, D is
a cathode ray tube (CRT), E is an electrolytic capacitor, F is a heated cathode in a
vacuum tube, G is a flashlight battery, H is an early receiver crystal detector, I is
a magnetic audio recording tape, and J is phonograph cartridge. I scored...
 Even with the domination of LED, plasma,
and LCD displays, there are still a whole lot of cathode ray tubes (CRTs) on the
job. Hobbyists workbenches are filled with them for sure, but design and manufacturing
facilities still have huge inventories of test equipment with CRTs, and a lot of
computer equipment on the production line with CRTs sitting in racks. LED, LCD,
and plasma displays all have their own claims to genius on the part of their designers,
but cathode ray tube designers - and the designers of the driver circuits - deserve
special recognition. Consider the physics and materials involved: glass, phosphor,
magnetics, thermonics, electrostatics and electrodynamics, relativity (electrons
traveling at relativistic speeds gain mass, requiring stronger deflection
fields)...
 Here is an advertisement by
Emerson Radio and Television from the November 6, 1948, edition of the The Saturday
Evening Post. By 1948, America and the free world was well into the
conversion of wartime production back into commercial and consumer products.
After many long years of allocating factory space, personnel, and resources to
beating back the forces of Communism, Marxism, Socialism, and other evil forms
of 'isms," the good times were returning. FM radio broadcasting stations were
increasing rapidly in number, providing static-free listening even in areas of
weak reception. Television was still a relatively new phenomenon for most
households. The tabletop Model 571 "Image Perfection" television carried a price
of $299.50 in 1948, which is the equivalent of a whopping $3,186* in 2018...
 When you read a lot of tutorials about
introductory electronics on the Internet, most are the same format
where stoic, scholarly presentations of the facts are given. Those of you who don't
have enough fingers and toes to count all of the college textbooks like that which
you have read know of what I speak. When hobby articles are written in a similar
fashion, it can quickly discourage the neophyte tinkerer or maybe even a future
Bob Pease. QST has printed a plethora of articles over the years that are
more of a story than just a presentation of the facts. My guess is the reason is
because often the authors are not university professors who have forgotten how to
speak to beginners. This article on basic calculations for AC series and parallel
circuits is a prime example...
 Unlike those IQ tests conceived of and administered
by Ph.D. college professors with pulsating veins in their foreheads, this "Electronics
IQ Quiz," created by Popular Electronics quizmaster Robert Balin,
is a true measure of your real-world acumen. Here are a couple hints to assist
quiz takers not familiar with last century electronics. You need to have
knowledge of the NTSC-mandated broadcast television channel bandwidth for figure
A, but you might be able to guess it by process of elimination. For figure E,
consider the bandwidth limits in terms of dB, not MHz. Kinks in the
characteristic curves of the tube alluded to in figure D betray its number
(extra hint: it's not a diode or a triode). Good luck...
 "The boy and his father had just witnessed
a demonstration of one of the most promising and fastest developing technological
devices ever conceived by man - the laser. In only three whirlwind years, the laser
- which gets its name from the initials of Light
Amplification by Stimulated Emission of Radiation - has moved
out of the theory stage, out of the laboratory curiosity category, and into a whole
new, exciting world of applications." That's the opening of an article in the July
1963 edition of Popular Electronics. I remember when ruby lasers were the
the rule rather than the exception for lasers. Power levels were measured in units
of 'Gillettes' in reference in the number of razor blades they could cut through.
Next came chemical lasers with power levels in the megawatts and now even gigawatts
that can take out ICBM warheads as they reenter the atmosphere and can fry orbiting
satellites...
 Being the birthday of Dr. Robert W.
Wilson, there is no better occasion to post this article about the "sugar-scoop" antenna used by the two Bell Telephone Labs engineers
(the other being Dr. Arno A. Penzias) who serendipitously discovered the cosmic
microwave background radiation (CMBR) believed to be a signature of "The Big Bang."
The pair were investigating an unexplained hiss in the background of the very low
noise receiver attached to the antenna. That microwave energy was constant and came
from all areas of the sky, regardless of where the antenna was pointed. They eventually
deduced that the signature was consistent with...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (6/18 - 6/22)
"Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid
cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle
using only words from my custom-created 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...
 Someone sent me a link to a viral video of a group
of teenagers (aka "Millennials") attempting to use an old school dial type telephone.
Two things are notable. #1: They do not remove the handset from the cradle prior to dialing.
#2: One of them asks whether it is necessary to let the dial spin all the way back to
rest before dialing the next number. It's really not their fault since except for in
dusty old places like my house, finding a dial phone is difficult. Many historians have
commented that two innovations most responsible for America's greatness in the last century
were the interstate highway system (for moving goods) and the telephone system. Bell
Telephone Labs engineers designed phones and all the equipment that connected them to
be simple, highly functional, robust, and to have... |
