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As advanced automation continues to infiltrate
industries around the world, Orbel Corporation has ensured that its board level
shielding products keep pace with today's newest automation technologies. Designed
as a starting point that leads to a fully custom EMI/RFI suppression solution, Orbel's
extensive line of board level shields offers unlimited design flexibility for components
needed for the parts and systems that contribute to automated technology. Based
on an unwavering attention to detail and delivering exceptional customer service,
Orbel
board level shielding can also be custom-engineered...
Mr.
Bob Hawkins would like to introduce Centric RF. "We're a start up company
planning to offer from stock various RF and microwave coaxial components, including attenuators, adapters,
cable assemblies, terminations, and more. Having started in June 2015, it will be
a few months before we have a large selection and we're fully staffed. Currently
we're in the design and procurement phase. When we finish parts for inventory we'll
add them to [the website] in case they fit a customer's need; shipment will be within
24 hours until we're staffed, then it will be same day shipment. We're currently
looking for vendors to partner with us." If interested please contact Bob at
sales@centricrf.com
Not so long ago the availability and usage
of
lasers was restricted to laboratory and military use, but today
they are ubiquitous in our world. CD, DVD, and Blu-ray players are found in nearly
every home and office. Laser pointers (including the green
ones being illegally targeted on aircraft), laser distance measuring devices,
laser leveling and alignment tools, laser light shows, laser cutting, even laser
weapons can be found in many other venues, and a relatively low costs
(except the weapons). Half a century ago, most lasers
were fabricated from
rare earth elements whose output powers were measured in a few
milliwatts at most. The cost of even a low power laboratory experimental device
was thousands of dollars. I can remember seeing something like a 0.5 mW helium-neon
laser for hobbyists offered by Edmund Scientific back...
"There
are two kinds of countries: Those that use the metric system and those that have
sent men to the moon." - Anon
A lot of engineers, technicians, and even
managers I have worked with over the years have been musicians that play in private,
with small gatherings, or even as a part of for-hire bands. It is probably safe
to say the opposite is not true - that many professional musicians are also accomplished
technologists. Jared Cossaboom of Circa Interactive sent me a hyperlink of this
infographic titled "Electrifying Music: A Closer Look at Engineering's Impact on Music"
as created by the NJIT. I particularly like the introductory juxtapositioning of
Nikola Tesla and Thomas Edison as representatives of AC and DC electricity, respectively...
everything
RF is a product discovery platform for RF & Microwave Products and Services. We list over 100,000
Products from more than 200 Companies across 200 Categories in our database and
enable engineers to search for them using our customized parametric search tool.
The parametric product search tool on everything RF has been designed to replace
paper and PDF catalogs. It is fast, easy to use and very powerful – You can enter
your specs and find products from multiple manufacturers that meet your requirement.
You can then compare products, download datasheets...
At below $10 in volume, the Hummingbird platform
is the lowest cost complete wideband transceiver with microcontroller module on
the market today. The
HumDT™ Series transceiver is built on this platform and is designed
for data transfer. Linx is pleased to announce the addition of the HumDT™ multi-channel
low cost RF modules in 868 MHz. Having a common footprint with the 900 MHz
frequency agile model, designers can now serve the North American and European markets
with common footprint modules, saving design time and material costs. Like its namesake,
the low cost Hummingbird modules are tiny. At 11.5 mm by 14.0 mm, the
HumDT™ uses advanced SOC Linx-Technologies-HumDT-Multi-Channel-Transceiver-Module-868-MHz-6-29-2015.htm"...
Skyworks Solutions, through its subsidiary
Trans-Tech, Inc., unveils webCRaFT,
a new Web-based ceramic bandpass filter selection program. Customers can easily
search for bandpass filter solutions by defining target performance criteria. Frequencies
range from 300 to 5000 MHz and bandwidths from 2% to 25%. Filters outside of those
boundaries are available upon request. To learn more, please visit
Trans-Tech webCRaFT.
Did you know that some radio service equipment
can be financed by the Federal Housing Administration (FHA)?
That's right, if your business needs a new tube tester or maybe an oscilloscope,
Uncle Sam is there to help. That was in 1936, anyway, per this
Radio-Craft news blurb. Today, of course, the FHA no longer
makes loans for business equipment - the Small Business Administration
(SBA) takes care of that. Nowadays the FHA restricts
itself to home loans - including to illegal residents and otherwise traditionally
unqualified. Also reported, among lots of other interesting stuff, is some early
instances of RFI (radio frequency interference) emanating
from...
Cobham Antenna Systems, a market-leading supplier
of antennas, has developed a range of
dual-polar MIMO sector antennas covering the UHF, 2 GHz,
3 GHz, 4 GHz and 5 GHz bands. The range offers excellent coverage
(azimuth beamwidths 60°, 90° and 120°) with peak gains
of 14-17 dBi. All antennas in the product range include interleaved vertical
and horizontal polarised antenna elements within a single aperture. This results
in very compact, lightweight units with rugged and UV stable radomes. Performance
across the range is excellent and Cobham-Dual-Polar-Base-Station-MIMO-Sector-Antenna-Range-6-26-2015.htm"...
How often have we all mistaken "spooks" for
Barkhausen oscillations? Yeah, it's embarrassing, but we've all
done it. I can't tell you how many times as a kid I saw the tell-tale effects on
our old black and white TV and said, "Mom, can you remind Dad to do something about
those dang Barkhausen oscillations when he gets home from the newspaper office?"
If you believe that line of bull hockey, I've got some waterfront property in the
Sahara Desert to sell you. The only thing close to 'Barkhausen' I might have known
back then was the name of a German beer house on Hogan's Heroes. Anyway, this article,
written in the days of over-the-air television broadcasts, presents a solution to...
Werbel Microwave's Model
WMDC10-0.3-2.7-S
is a wideband 10-dB directional coupler that operates continuously over the frequency
range of 300 to 2,700 MHz. Designed for wideband telecom applications. Covers
all major commercial bands including Cellular, PCS, WiMax, LTE, Public Safety and
UHF. Materials selected for low intermodulation Werbel-Microwave-10-db-directional-coupler-6-26-2015.htm"
...
Long before there were smartphones and software
'apps,' engineers and scientists carried around portable 'apps' of another kind.
These apps were made from printed heavy cardboard stock and typically had either
a sliding section sandwiched between two outer layers, or a rotating layer on a
fixed base layer. They even sported rivets to hold them together - like the original
Levis dungarees. I and guys much older than me [ ;-)
] routinely carried them in our shirt pockets, securely snugged behind out
plastic pocket protectors. You definitely always wrote your name
on them in indelible ink since there was a tendency for those cardboard slide rules
to sprout legs and walk away while you were at lunch or in the can. RF Cafe visitor
Neil Blaho just sent photos of some rare gems for your opportunity to wax nostalgic
...
Wow, six weeks have gone by since last posting
a list of engineering career advice article links. May and June have been
quite busy. The good thing about having waited so long is that there is a huge crop
of such articles to choose from now. The first one has a slightly nonsensical title,
until you realize Ms. Herman means 3 second per tip. She has also gone to the
trouble of limiting each tip's length to 140 characters or less for facilitate your
Tweeting one or more to a friend. Thoughtful of her, non?
-
101 Career Tips You Can Learn
in 3 Seconds
-
The Secrets to a Great Online
Job Interview [Infographic]
-
How to React When an Interview
Doesn't Go as Planned <more>
RFMW announces design and sales support for a
series of voltage-controlled variable attenuators (VVAs)
from Skyworks Solutions. The SKY1223x series of attenuators is suitable for applications
such as repeaters, wireless backhaul and wireless infrastructure. The four attenuators
in the series,
SKY12232-21,
SKY12233-11,
SKY12235-11 and
SKY12236-11, are optimized for low distortion and centered at
1.95, 2.60, 3.15 and 3.8 GHz respectively. Together, the attenuators cover
operation from 1.45 to 5.0 GHz and have control voltages ranging from RFMW-High-Input-TOI-VVAs-6-23-2015.htm"...
Garod Radio Corporation, a shortened version
of the original Gardner-Rodman Corporation, operated out of Brooklyn, New York,
beginning in the early 1920s. Many of their models had a molded 'plastic' look long
before plastic was used in commercial products. The material appears to be a painted
or brightly stained type of phenolic substance. This schematic and parts list appeared
in the July 1948 edition of
Radio News magazine...
Anatech Electronics, offers the industry's largest
portfolio of high-performance standard and customized
RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. Anatech has released three new designs:
a connectorized 2260 MHz cavity bandpass filter, a surface mount 460 MHz
RF SAW bandpass filter, and a connectorized 1650 MHz cavity bandpass filter.
All can be ordered directly through their AMCrf web store.
Belmont Radio Corporation was located in
Chicago, Illinois. Founded independently sometime the 1920s, it became a subsidiary
of Raytheon Manufacturing after World War II in an effort to quickly launch
the Raytheon into nascent consumer FM radio and television markets. Belmont advertisements
were prominent in electronics trade magazines throughout the 1940s to promote their
war efforts. A schematic and parts list for this
Belmont Model 5240 receiver appeared in the July 1948 edition
of Radio News magazine...
According to the
RadioMuseum.com website, B.F. Goodrich manufactured the
Mantola line of radio receivers. It was evidently a low quality,
low price, short-lived run of models. The simplicity of the schematic shows the
low parts count. A lack of multipole filter circuits likely means selectivity was
fairly marginal. One good feature is that unlike many earlier radios and TVs, the
AC line connection to the chassis is DC-isolated through a 150 kΩ resistor.
Look at the schematics of older sets and it is not uncommon to see one line of the
AC supply tied directly to the metal electronics chassis. An isolation transformer
right at the input is the safest way to do it...
At the request of some of my former advertisers
and some new inquiries, I am now set up to once again host
private
advertising in the form of graphical banners in all page borders, and as textual
Highlighted Ads on the
Parts Vendor pages. I had stopped the advertising program at the end of 2014
in order to recover the rather large amount of time being required to manage all
the advertisers. Everything was replaced with 3rd-party ads from Google, GlobalSpec,
and Bing/Yahoo. However, a new plan is in place now that makes my job easier and
allows time to host private advertisers' needs. If your company is interested in
reaching RF Cafe's very diverse range of visitors, please review my
Advertising
Information page. Plans are available starting at $40 per month. Please pass
this announcement on to your company communications / public relations department.
Thanks for your support.
NI (formerly AWR Corporation) announces the availability
of the first major release in 2015 of NI AWR Design Environment™ for designers of monolithic microwave
integrated circuits (MMICs), radio-frequency printed circuit boards (RF PCBs), modules
and more. V12 was previewed for the first time at IMS 2015 in May 2015, creating
significant interest, and feedback from early-access customers has been very positive.
This latest release boasts new load-pull and antenna- and radar-specific features,
as well as ease-of-use improvements, speed enhancements and third-party integration
flows for improved stability analysis and design NI-AWR-Design-Environment-V12-Release-2015-6-23-2015.htm"...
As a case in point about my claim with today's
earlier post featuring Bob
Berman's factoids on astronomy, this article from a 1956 edition of Popular
Electronics illustrates how vital electronics are in the various fields of
science. It has only been fairly recently that astronomers have been 'looking' at
stars and planets outside of the visible wavelengths. Renditions of the sky in both
shorter and longer wavelengths show in some regions a vastly different universe.
Earlier this year, a comprehensive mapping of the entire known universe in the microwave
realm revealed the largest contiguous feature ever detected - dubbed "The Cold Spot"...
Most people reading this article are engineers,
technicians, academics, and hobbyists who appreciate the sciences and how they categorize,
define, and explain the world around us. I think it not inappropriate, then, to
present on occasion a few 'factoid' type pieces on topics not directly related to
RF and microwave engineering. Many, if not most, nay, if not all modern discoveries
are aided in part or in whole by the advent of electronics - even if that bit of
electronics is a computer that crunches numbers for analysis, simulation or processing
words in a technical paper. Accordingly, you will probably appreciate these few
short tidbits of astronomical
information which überprolithic astronomy author and practitioner
Bob Berman wrote for
the 2015 edition of The Old Farmer's Almanac (aka OFA)...
Foundations of Antenna Engineering: A Unified
Approach for Line-Of-Sight and Multipath, by Kildal Per-Simon. This is the first
textbook that contains a holistic treatment of antennas both for traditional antennas
mounted on masts (line-of-sight antenna systems) and
for small antennas used on modern wireless devices such as smart phones being subject
to signal variations (fading) due to multipath propagation.
The focus is on characterization, as well as describing classical antennas by modern
complex vector theory - thereby linking together many disciplines such as EM theory...
Please support RF Cafe with your purchases.
This is one of the earliest examples I have
seen (and I've seen many) of an electronics article that was written in a conversational
tone rather than in the heretothen[sic] stoic, all-business type prose. In fact,
you would be hard pressed to discern it from a contemporary article in QST. Author
Davis describes his process of interfacing 52 Ω coaxial cable to his
multi-element beam antenna. The
gamma match has the advantage in such an application of being
usable when the center of a driven element is directly grounded to the antenna boom. Most
other types of feed systems require that the driven element be isolated from the
boom. BTW, SWR ratios are written here with slashes as the ratio...
For the sake of avid cruciverbalists amongst
us, each week I create a new
crossword puzzle that has a theme related to engineering, mathematics,
chemistry, physics, and other technical words. You will never be asked the name
of a movie star unless he/she was involved in a technical endeavor(e.g., Hedy Lamar). Enjoy...
I've been so busy making website changes
that refreshing the list of RF & microwave industry magazine articles has been
neglected. One of the many advantages of the Internet is that we no longer have
to wait for a once-per-month publication to arrive in the mail in order to be able
to read useful write-ups. Three weeks have passed since the last suggested reading
list, so here is an update.
-
Top Methods for Measuring 5
Common Signal-Corrupting
Distortions, J-J DeLisle
-
Controlling EMI in the Microwave
/RF Industry, Ed Nakauchi
-
Gauging IMD/PIM in Microwave
Components, Jack Browne <more>
"This mode of instantaneous communication
must inevitably become an instrument of immense power, to be wielded for good or
for evil, as it shall be properly or improperly directed."
Samuel
F. B. Morse, in an 1838 letter to Congressman and business partner Francis O.J.
Smith, of Maine.
COMET Technologies USA has an immediate opening
in our Plasma Control Technologies (PCT) group for a qualified Mechanical Designer
to work in our San Jose, CA office. This is an outstanding opportunity to learn
from and work with experts in high power RF products in the semiconductor industry.
Key responsibilities include designing and completing SolidWorks designs to ensure
all BOM parts are included in the 3D models with correct material designations,
generation of data records for piece parts and assemblies when is needed, and logging
the data into the SAP system, work closely with COMET's R&D RF and mechanical
engineers to complete new...
Z-Communications is pleased to announce the release
of a new
Product Selection Guide. This short form catalog includes a wide
variety of surface mount VCO (Voltage Controlled Oscillator)
and PLL (Phase Locked Loop) synthesizer modules ranging
from 40 MHz to 15 GHz. Users can download an electronic version of the
product guide in PDF format or contact the company for a hard copy version. A complete
listing of all available parts and specifications can be found on the Z-Comm's web
site Z-Comm-Releases-2015-Selection-Guide-6-22-2015.htm"...
This article
from the May 2015 edition of the Smithsonian Institution's
Air & Space magazine reports on the latest trend amongst
the überwealthy in California where their children are encouraged to earn helicopter
pilots licenses. Doing so has become a major status symbol. Price, which can range
from $100k to $½M depending on the age the kid begins, is no object for those folks.
"Instead of sports after school, parents are putting their kids in helicopters.
They think having a helicopter pilot's license on an application will help their
kids get into college." "As soon as he gets his pilot's license, his dad wants to
buy a helicopter so his son can chauffeur him around." It gives a new meaning to
the term "helicopter parent."
Crowded frequency bands have been a problem
since the beginning of radio because technology is constantly not only filling available
bandwidth, but also pushing the frontiers higher. The advantage of going higher
in frequency is that required bandwidths for existing modulation schemes represent
a smaller percentage of the center frequency. For example, an 802.11b WiFi signal's
22 MHz bandwidth represents roughly 1% of its 2.4 MHz center frequency.
802.11a does 20 MHz at 5 GHz for 0.4%. Extend that center frequency up
to 50 GHz and the channel occupancy is a mere 0.04%. That means for the same
total band occupancy of 1% as with 802.11b, you can fit in 25 equivalent slots.
The problem with going higher in frequency is that components...
As mentioned many times in the past, some
things never change regarding the
basics of electricity and electronics. Resistance, inductance,
and capacitance are examples. When first starting out in this science, an effective
introduction to the fundamentals can often determine whether a person sticks with
it or finds another area of interest to pursue as a hobby and/or vocation. Analogous
examples of voltage and water pressure, resistance and the diameter of a water hose,
inertia in a spinning mass opposing a change in rate and an inductor opposing a
change in current, etc., are presented along with some good sketches of...
Yea! Finally, another good
Sherlock Ohms story, and this one concludes without having solved
the mystery. Author
Chuck Bagg describes an experience he encountered four decades
as an electronics test technician shortly after leaving the U.S. Air Force. It has
all the makings of a great techie head scratcher: a meter movement, a battery, a
length of RG-178 coaxial cable, and an unexplained voltage spike. A few people have
offered possible explanations, but nothing definite has yet been posted. Give it
your best shot and help Mr. Bagg end his career in peace ;-)
COMET Technologies USA has an immediate opening in our Plasma Control Technologies
(PCT) group for a qualified RF Test Engineer to work in our San Jose, CA office.
We are seeking a team player who will bring their extensive RF product development
knowledge and experience to our product development team. This is an outstanding
opportunity to learn from and work with experts in high power RF products in the
semiconductor industry. Required skills include final test of RF matching network
assemblies, test of components and assemblies, develop automated test routines for
accelerated life testing , design validation testing and production final testing
of RF...
As quoted in this article about
analog[ue] computers as compared to digital computers, "Add two
and two. Coming from an analogue computer, the answer would most likely be, 3.999
or 4.001." While that is a true statement, there is one important feature that an
analog computer had over digital computers of the era: once initially set up with
a transfer function, outputs were nearly instantaneous as the input was varied over
a range of values, whereas a digital computer could take quite a bit of time to
crank through involved mathematical equations. Performing tasks such as computing
aircraft flight paths and other sequential operations was the analog computer's
forte. If you...
Ken Lemke completed
his career in the USAF just as mine began. He worked on the vacuum tube based
MPN-13 mobile radar system after
tech school at Keesler AFB, Mississippi, switched over to the transistorized
TPN-19 mobile radar system,
and eventually ended up as an instructor back at Keesler AFB. Ken didn't say whether
he volunteered for instructor duty at Keesler or whether he was randomly issued
orders. Even if it was an unplanned assignment, it was better then having been sent
back to Lackland AFB as a TI (training instructor, as opposed to DI, drill instructor,
in the Army)...
Carl and Jerry found the appearance and construction
of 2400 megacycle transmitters and receivers to be quite odd compared to the equipment
they were used to dealing with. It's sometimes hard to believe such an attitude
of wonder when our world today is utterly filled with wireless devices operating
in the 2.4 GHz ISM band. Author John T. Frye could never have imagined
that such a reality would would exist half a century after his story of the pair
of teenage electronics sleuths. Unlike our postage stamp size integrated assemblies
that cost a few dollars, they speak of "special ultra-high-frequency "light-house"
tubes with...
Skyworks introduces a series of Skyworks-Variable-Attenuators-Broad-Wireless-6-18-2015.htm" >voltage-controlled
variable attenuators (VVAs) which are designed to have excellent third order input
intercept point and superb dynamic range. The devices cover operation from 1.45
to 5.0 GHz, and have control voltages ranging from 0 to 5.0 V. The
SKY12232-21, SKY12233-11,
SKY12235-11
and
SKY12236-11 are optimized for use as low distortion, analog attenuators – centered
at 1.95, 2.60, 3.15, and 3.8 GHz. These VVAs are ideal for automatic power Skyworks-Variable-Attenuators-Broad-Wireless-6-18-2015.htm"...
The
good folks at everything RF have just added a few new online calculators for opamp
circuits. Included are:
- Current to voltage converter
-
Voltage to current converter
-
Differential voltage amplifier and common mode rejection ratio (CMRR)
-
LLog amplifier
-
Non-inverting gain for ideal and non-ideal opamp
-
Output of a summing opamp
How is this for a prescient prediction from
the early 1960s? "As a result of modular and
integrated circuitry techniques, all future circuit design work,
regardless of degree, will become the responsibility of the component manufacturer
instead of the equipment producer." Texas Instruments' (TI) Jack Kilby is credited
with designing the first integrated circuit in 1958. The first commercial IC, Ti's
Type 502 flip-flop, had just hit the market in early 1960, and already pundits were
prognosticating and ruing the disappearance of circuit designers. Maybe it was concerns
over job security that they seem to favor forever building every circuit...
COMET Technologies USA has an immediate opening in our Plasma Control Technologies
(PCT) group for a qualified RF Engineering Manager to work in our San Jose, CA office.
The successful candidate will manage a team of engineers and technicians to develop
custom RF matching network products for plasma process tool, develop a product portfolio
and technical solutions for a specific market segment, participate in the factory
release of products developed by your team, identify and allocate resources to staff
projects for internal and external customers, assist...
NI (formerly AWR Corporation) announces that the accompanying
example project files for two recently released application examples -
Design and Simulation of a 2.4 GHz/5.6 GHz WLAN Antenna on PCB Technology
and
Design and Simulation of an ISM Band Antenna on PCB Technology
are now available for customers and evaluators to download (registration required)
NI-AWR-Design-Environment-Software-Antenna-Examples-6-17-2015.htm" ...
For the benefit of hobbyists who restore and
service vintage electronics equipment, I occasionally scan and post
Radio Service Data Sheets that appeared in electronics magazines.
Most - if not all - electronics servicemen had subscriptions to these magazines
because they were a ready source of not just data sheets, but also extensive articles
offering advice on servicing radios and TVs. Many electronics manufacturers had
a policy of supplying service data only to bona fide shops. Of particular interest
for the Zenith Farm Model receiver is an included wind-powered electricity generator
meant to supply power in a rural location...
-
Philco Model 59, 4-Tube A.C. Midget Superheterodyne
-
Zenith Farm Model 6V 27, 6-Tube Superhet
-
Ward 10-Tube All-Wave High-Fidelity Superhet, Series ODM
The Art and Science of Ultrawideband Antennas,
by Hans Schantz, is a new publication released by Artech House. Along with theoretical
formulations behind the engineering, this book is chock full of examples of actual
antennas with very unusual shapes, and there is a nice chart of the evolutionary
timeline of
UWB antenna development that dates back to Maxwell in the 1800s
(a nice wall chart candidate for the lab if the publishers would enlarge and colorize
it). "This comprehensive treatment of ultrawideband (UWB) antennas and time-domain
microwave engineering serves as an invaluable practical reference for anyone involved
in antenna and RF design work. This authoritative volume enables...
by COMET Technologies
COMET Technologies USA has an immediate opening in our Plasma Control Technologies
(PCT) group for a qualified RF Engineer to work in our San Jose, CA office. We are
seeking a team player who will bring their extensive RF product development knowledge
and experience to our product development team. This is an outstanding opportunity
to learn from and work with experts in high power RF products in the semiconductor
industry. Our San Jose PCT engineering team works in a technical, entrepreneurial,
...
Mrs. Helen McKee knew exactly what she was
signing up for when she agreed to marry Mr. McKee. After all, she met and got familiar
with the guy over the air during some rag chewing sessions. This story is a humorous
(and true) account of what life can be like for the
spouses of enthusiastic Ham radio operators. We all hope for such an understanding
"significant other." Melanie has certainly endured and supported a lot of
my pastime endeavors
over the past 32 years. It's a short read, so take a break and put a smile on your
face...
I saw this photo with some news story the
other day. It is from the Cold War era "Duck and Cover" drills
that kids used to do in school in the 1950s and 1960s. The idea was upon hearing
the civil defense siren, you needed to crawl under your school desk and cover your
head, and remain there until the "all clear" was given. When I saw this picture,
my first thought was how stupid the one kid must have been to have his head and
back not even under the desk. He might as well be standing in the middle of the
room. Then it occurred to me --- that's probably exactly what I did during our duck
and cover drills. Maybe...
West Virginia ARRL Section Manager Charles
Hardy, WV8CH, of Fayetteville, died June 14, apparently as the result of an
accidental electrocution while he was working on an antenna at his home. He
was 50 and had been a radio amateur since 2008. Hardy became West Virginia SM in
October 2013. Hardy was the President of the Plateau Amateur Radio Association (PARA) and of the Summit Repeater
Association. Survivors include his wife, Jane, WV8JH. RIP...
Coaxial cable is the most familiar form of
RF transmission line for most people these days. Up until 2009
when the U.S. switched to digital television (DTV), there were still a fairly large
number of people who had the old 300 Ω twin lead cable running from roof-top
antennas to TV sets. Over-the-air reception has petered off precipitously since
then. Coaxial cable is undoubtedly more convenient and forgiving regarding routing
since proximity to structures - particularly metallic components - than twin lead.
Good quality 300 Ω twin lead cable (~30¢/foot today)...
"Mediocre hires are like empty calories: They
make you bigger but less healthy." -
Eric Ryan, Method and Olly founder, in June 2015 Inc magazine
article titled "Playbook: The Fine Art of People."
UK-based artist
Julie Alice Chappell
has given a whole new meaning to
electronic component
bugs with her array of hand-made bugs and butterflies fabricated from recycled
electronics parts. Resistors, capacitors, inductors, integrated circuits, connectors,
pins, circuit boards, connectors, switches, adaptors, wire, batteries, terminals,
insulation, mounting hardware, oscillators, and other types of components are fair
game for inclusion in her handiwork. Some items like the transparent wings are made
from "reclaimed acetate," but the majority appear to come from discarded electronic
appliances. Those amazingly detailed wings are hand-painted based on examples...
It's been quite a while since I linked to
a
Sherlock Ohms; they subjects just haven't been piquing my interest
like in the past. This one, however, touches on the subject if proper fuse design,
which includes proper placement for servicing. I just posted an article titled "Selecting the Proper Fuse," from Electronics World so
this is a timely coupling of pieces on fuses.
In an effort to promote entry of women and
girls into the amateur radio hobby, Short Wave Craft magazine ran a few
contests for Best "YL" Photos. Amazingly - and maybe there are still instances
of it today - many (if not most) of the YLs featured had built their own equipment.
In 1935, most people built their own equipment, so that is not too surprising. The
winner for this month was a 16-year-old young lady i.e., "YL") who in fact built
her rig. Another winner was an 83-year-old grandma who was born before Marconi,
Maxwell, and Hertz did their best work! The third winner was a girl who earned
her Ham license at age 6, which back in the day required sending and receiving 5
words per minute (WPM) in Morse code...
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