These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
Anatech Electronics offers the industry's largest
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filter-related products for military, commercial, aerospace and defense, and industrial
applications up to 40 GHz. Anatech has released new designs for a 1575.4 MHz ceramic
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directly through their AMCrf web store.
Skyworks Solutions, Inc. unveils a low threshold,
PIN diode limiter module that addresses the growing need for receiver low noise
amplifier protection in microwave applications. The
SKY16602-632LF is a fully integrated module comprised of a PIN limiter diode,
a Schottky diode and two DC blocking caps designed for use as a passive receiver
protector in wireless or other RF systems up to 4 GHz. It is targeted for broad
market wireless systems
You have probably seen
Fahnestock clips, but did you know that's what they were called?
Me neither, until I first saw the name of them on a page in a MicroMark catalog
a while back. When I saw this ad in Radio News, it seemed like a good opportunity
pass it on. You can still buy Fahnestock clips from MicroMark. Model train enthusiasts
use them for wiring their layouts since they facilitate...
You might have noticed
a new layout for RF Cafe this morning when visiting. It is something I have been
wanting to do for a long time, based on the information available from major search
engine companies and the plethora of 'experts' regarding expectations and requirements
for modern Web users. The term used for optimizing website structure and page content
is 'Search Engine Optimization' (SEO). Many of the most highly recommended
tactics have not been possible because of the fundamental structure of RF Cafe,
which has been necessitated by commitments made to advertisers and by long-held
preferences of my own. The time for major change has come, and it began a couple
SigaTek microwave specializes in
high quality, high frequency microwave communication
components up to 60 GHz. As a pioneer supplier of
microwave RF components, the main products include
directional couplers, bias tees networks, power dividers/combiners, 3 dB hybrids
90° and 180°, microwave mixers, frequency doublers, load terminations, and coaxial
connectors and adapters.
MECA serves all areas of the
RF/Microwave industries including world class
network providers, and supporting supply chain infrastructure. We have long been
the "backbone" of high performance wired and air-interfaced networks such as in-building
applications, satellite communications, radar, radio communications, telemetry applications,
mobile radio, aviation & air traffic communications.
'Dilbert' will remain popular as long as employees are frustrated and they fear
the consequences of complaining too loudly. 'Dilbert' is the designated voice of
discontent for the workplace. I never planned it that way. It just happened." -
Here is the latest group of
vintage radio schematics and parts lists that appeared in a 1947 edition of
Radio News. I know most visitors have no need for them, but
posting them on the homepage helps get them into the major search engine databases.
Google, for instance, scans RF Cafe every few hours, so these will be searchable
by later today.
Wards Model 74BR-1055A,
Farnsworth Models EK-081, EK-082, EK-083, EK-681,
Philco Model 200-X Radio,
Admiral "Aeroscope" Models 161-5L, 162-5L and 163-5L Midget Set Radios,
General Electric Model 280,
Zenith Models 5R080, 5R086,
Truetone Models D1747, D1748,
Hoffman Model A301,
Knight Model E10716 Battery Portable Radio
TradePub is a service that
offers (and book excerpts), magazine subscriptions and whitepapers
to qualifying engineers and technical professionals. I have downloaded many over
the years and find them to usually be useful. This group happens to be related to
career advancement, but the topics are widely varying. I can honestly say that I
cannot ever recall being placed on any kind of annoying list as a result of signing
Blame my soft spot for
Ford Mustangs for the reason I feel compelled to promote this installment of EDN's
Sherlock Ohms, even though its subject doesn't pertain to directly to electronics.
Sherlock Ohms articles all focus on troubleshooting problems whether they be mechanical,
electrical, or a combination thereof. In this case, the electrical problem - a computer
that erroneously caused the engine to run in a lean fuel mixture mode - was caused
by a mechanical problem - a clogged PCV device. It has admittedly been many years
Engineering crossword puzzle's six longest words begin with the same letter.
I give it a grade of 'A' for effort. As always, every word, sans none, is related
to technology. Enjoy.
"The term, positive current
feedback, is disturbing to some because, as is well known,
positive feedback increases the distortion of an amplifier to
which it is applied. This is true in this application also, but it must be noted
that the net feedback applied to the amplifier is never positive but simply less
negative in the region where the positive current feedback is effective." Wow, that
is a lot like what politicians refer to a 'baseline budgeting.' When...
A wee bit of levity in the
comics is good for the soul on Friday, the last day of the work
week - just a few more hours to go until two days of freedom. Good humor, it is
said, contains a degree of truth in it, and this group from vintage editions of
Radio Craft magazine is no exception. One of the comics in particular struck a chord
with me - the one with the table model radio where the serviceman is speaking on
the phone with his customer. The first familiar feature is the shape...
Homodyne reception, although
we don't often refer to it today using that term, involves mixing the modulated
signal with a local oscillator that is tuned to the same frequency so that the demodulated
signal is at baseband. In other words, the result of a
homodyne nonlinear mixing process is a sum frequency of 2x the
signal input and the difference frequency is DC (at the low end of the modulation).
That is a simplistic explanation, and this article goes into a little more detail
about methods, advantages, and disadvantages
This is a really nice
electronic symbols chart that will come in handy for hobbyists
who work with vintage electronic equipment. Not only does it have component symbols
that a modern chart would not likely contain, but it has three-dimensional sketches
of each device. It's too bad the chart is not in color because it would make a nice
picture to frame for a decoration. If anyone with an artistic bent feels compelled
to colorize it and send it to me, I'll be glad to make it available to visitors...
There is no limit
to the amount of advice offered by helpful 'experts.' It's time for another round
of job hunting and career advice stories. Many of these particular bits of guidance
for your life come from authors on LinkedIn, Monster, Money, etc., which typically
do have good content...
10 Little-Known Facts About Quitting Your
Corporate Job - LinkedIn
Fear as a Management Technique - Forbes
3 Ways to Wow Your Interviewer - U.S. News
The 3 C's of Leadership from the World's Top
Executive Coaches - American Management
I don't know
Michael Dunn, but every time
I see his picture on the EDN website it makes me think he's got to be a good guy
to work with. After all, how many people post a picture of him/herself on a professional
website with a soldering iron between his/her teeth? Where is OSHA when you need
them? ;-) What got my attention this time was a picture in an article titled
"Electronics of Our Youth" of a
Heathkit ET-3100 Experimenter like the one I had many moons ago. The function
generator in mine fried twice (replaced it once) just from being overloaded
with too little external circuit impedance - poor design IMHO.
Barkhausen-Kurz (B-K) oscillator is credited as being the first
high power microwave generator that exploited the electron transit time effect.
It was developed in 1920 by German physicists Heinrich Georg Barkhausen and Karl
Kurz. As this article's author points out, the vacuum tube and supporting circuits
were difficult to produce and were not very well understood theoretically. Shortly
thereafter, the magnetron and klystron tubes came along and dominated the high power
microwave generation realm. This is a good, brief explanation of...
Test is a trusted source providing sales, rentals and leasing of
refurbished electronic test and measurement
equipment to the R&D, manufacturing and quality assurance industries. We
carry a full range of used test equipment from manufacturers such as Agilent, Ando,
Anritsu, Fluke, HP, Keithley, Lecroy, Rohde & Schwarz, and Tektronix. Partnering
with Alliance Test to recover 30%-40% more on your idle test equipment rather than
selling to a dealer.
have written often about the many contributions that hobbyists make to various fields
of technology. Often times the efforts put out and methods used by amateurs are
on par with those of professionals; the main difference between the two being that
amateurs do not get paid for their work. This archived BBC video titled "Wartime Radio:
The Secret Listeners," sent to me by longtime RF Cafe contributor Gary
Steinhour documents how the work of two British amateur radio operators, Russell
Clark and R.J.B. Hippisley, resulted in a significant strategic
Rohde & Schwarz and
Mesuro showcase their continuing
collaboration on Non-Linear measurement solutions at European Microwave Week in
Rome. In a joint demo at the Rohde & Schwarz booth (hall 9, booth 102), the
companies present their testing solution based on the R&S ZVA vector network
analyzer from Rohde & Schwarz and Mesuro's behavioral modeling formulations.
The Cardiff Model Lite solution allows
Modeling, and Design of Nonlinear RF and Microwave Components, by D. Root,
J. Verspecht, J. Horn, and M. Marcu. This is the definitive guide to X-parameters,
written by the original inventors and developers of this powerful new paradigm for
nonlinear RF and microwave components and systems. Learn how to use X-parameters
to overcome intricate problems in nonlinear RF and microwave engineering. The general
theory behind X-parameters is carefully and intuitively introduced, and then simplified
down to specific...
World War II brought
about the first
wireless remotely controlled weapons. Prior to radio technology,
bombs and missiles needed to either be within a distance serviceable by detonation
wires, or were set off using mechanical or electrical timers. Both of those methods
required the operator to gain access to the target area at a time relatively close
to when the attack was to occur. Army battalions did have warheads with spooled
wires attached that enabled them to control the time of detonation and even in some
instances some degree of steering, but range was limited. Wireless...
Comdel designs and
manufactures RF and DC power supplies and process
instruments for the semiconductor, solar cell/photovoltaics, flat panel, and industrial
heating industries. Comdel products are in use worldwide by the industry's major
equipment and IC fab manufacturers.
RFMW, Ltd. announces design and sales support
for TriQuint's TGP2615 digital phase shifter. The TGP2615 covers Ku-band radar and
communications applications in the 15-19 GHz frequency range. 6-bit control
with 5.625° LSB offer high resolution and 360 degree coverage. Insertion loss
of the TriQuint TGP2615 is 7 dB. RMS phase error is specified at 4° while RMS
amplitude error is 1 dB. The TriQuint TGP2615 is available as a
The main purpose for bothering
to reprint articles like this one on
analog color TV theory is to reveal the complexity and ingenuity
that went into cramming a lot of information into a relatively (at the time)
small bandwidth. Signals within signals and signals riding on top of and below other
signals was the name of the game, and pulling it off successfully required many
well-designed and well-aligned circuits. Anyone old enough to remember watching
a show on analog television can appreciate the difference between a high quality...
"An expert is a person
who has found out by his own painful experience all the mistakes that one can make
in a very narrow field." - Niels Bohr, as quoted by Edward Teller, in
Dr. Edward Teller's Magnificent Obsession, in LIFE magazine
Since 1994, leading wireless electronics companies
have relied on 3Gmetalworx to deliver cutting edge solutions for advanced
RF/EMI PCB-level shielding
requirements. From prototyping and design services to JIT manufacturing supply,
our clients depend on us to provide a seamless service pathway supporting entire
EDN's Kenneth Wyatt visited
ARRL headquarters building recently and posted a short story and
some photos on the EDN website. The focus of the visit was ARRL's RF test lab and
its RF interference expert, Michael Gruber, but there are also has some photos of
archival items from days of yore.
design for a coaxial line
RF monitoring instrument uses components still readily available
since it has no vacuum tubes and you can still buy the 1N34 germanium diodes that
are used as detectors. Only 18 components (including jacks, meter, case, and switch)
are used to indicate relative power, modulation percentage, and to monitor the signal
modulation. Sampling is done with a high impedance tap on a through connection
so that the impact on characteristic impedance on...
When civil engineers
and mechanical engineers take their introductory classes in hydraulics, are the
taught that the functional equivalent of water pressure in a pipe is
equivalent to voltage in a battery, and that the rate of water
flow is equivalent to current in a circuit, and that the diameter and surface finish
of pipes are equivalent to resistance in electricity... in the same manner that
electronics students are taught from the opposite point of view? The answer is 'yes,'
they are. It's kind of funny how for some reason using an analogy from another familiar...
Technologies Corporation is a technology-transfer spin-off from the University
of Maine Laboratory for Surface Science and Technology. A dynamic research and development
organization, Environetix is making rapid and exciting progress in the field of
passive, wireless sensor systems for harsh environments. We have current openings
for both RF engineers and technicians who will participate in a team effort to develop
and manufacture wireless microwave sensors for custom high- temperature harsh environment
Engineering crossword puzzle includes the new name conjured up
by marketing gurus for the combined company formed by RF Micro Devices (RFMD) and
TriQuint. According to the press release, "conveys the combined company's ability
to deliver the core technologies and innovation that will enable customers to launch
their next-generation designs even faster." Let me just say the name is as intuitive
to me as 'Agilent' or Keysight.'
least for now, I am going to only scan and post Radio Service Data Sheets like these
Philco Model 200-X, the
Knight (Allied Radio Corp.) E10716
Battery Portable, and
Admiral "Aeroscope" Models 161-5L, 162-5L and 163-5L Midget Set
in graphical format, rather than run OCR on them to separate the textual content.
There are still many people who restore and service these vintage radios, and often
it can be difficult or impossible to find schematics and/or tuning information...
...as long as Capitalism is
allowed to flourish. I know, the claim is a non sequitur, and today's
Alibaba IPO is an ipso facto example. At the time of this writing, Jack Ma is
worth $17.5B. Mr. Ma is a citizen of Communist China, where
Chairman Mao, murderer of millions, is still idolized and his governmental tenets
are still followed. Xinhua News Agency headline: "Alibaba's
IPO to End US Dominance in Technology Sector." This comes as welcome news to
many members of the U.S. Congress and political appointees who have publically and
repeatedly cursed Capitalism...
Please welcome MSgt.
(ret) Terry Butman
as the newest member of the prestigious USAF Radar Technician Hall of Fame
(unofficial, though, it is). Terry recently contacted me with his 20+ years
of service information. Although not in a mobile communications group, Terry spent
most of his career working on mobile radars like the
MPN-13, MPN-14, and CPN-4. BTW,
original manufacturer ITT Gilfillan's radar division now goes under the name Exelis.
Hugo Gernsback, in
1938, lampooned his contemporaries who boldly declared that by then there was nothing
left to be invented regarding radio equipment for
short wave communications. Wisely citing the well-known instance
of a patent examiner who quit his post in 1870 because, as the man put it, all useful
things had been invented and there was nothing meaningful left to patent, Mr. Gernsback
challenged his readers to keep this article for 25 years and then go back and read
it while being aware of all the new and wonderful short wave devices that had been
invented since 1938...
Congratulations to Wouter
U., of The Netherlands, for being one of two winners in the August
book drawing. Wouter selected
Understanding Quartz Crystals and Oscillators, by Ramon M. Cerda. I pay
shipping so it costs the lucky winners nothing. Graciously provided by
engineer candidate will be responsible for the development and design of wireless
control systems which will be used in Kenall lighting, emergency and signage products.
The Ideal candidate will have experience using WLAN, ZigBee, Bluetooth, low-voltage
control and switching circuits. Kenall products are proudly manufactured in the
LadyBug Technologies manufactures
the PowerSensor™ line of miniaturized USB
RF & microwave power sensors. LadyBug manufactures high accuracy average,
pulse, and pulse profiling sensors with GUI interfaces covering up to 26.5 GHz
and 80 dB dynamic range. These sensors set a, patented industry standard, No Zero/No Cal
technology. There is no need to disconnect or wait for internal zeroing and calibration.
There is a plethora of comics with just about
any theme on the Internet. I could provide pages full of replications for your enjoyment,
but one of the best ways to sample available comics for personal consumption and/or
use in reports, presentations, etc., is to use the Search function on a website
like CartoonStock. The thumbnail image
above is great example where the anatomically correct mother, father, and son socket
and plug family have the inscription, "Sparky! Your mother and I are shocked at
your current behavior! Until you learn to conduct yourself properly, you're grounded!"
Thanks the incredible generosity of
Artech House publishers, there
are now many new engineering books available for selection to the monthly
RF Cafe Book Drawing
winners. The four shown here are among seven new titles.
Decoding the Heavens:
A 2,000-Year-Old Computer - and the Century-long Search to Discover Its Secrets,
by Jo Marchant. Discovered a century ago in an ancient Mediterranean shipwreck,
mechanism instantly attracted scientific interest. It had gears, which was and
remains unique among artifacts from Greco-Roman civilization. So begins Marchant's
mystery about the object, a tale that ends in triumph but not before inveigling
individuals who not only puzzled over the device but also became obsessively devoted
to figuring it out. Tantalized by the Antikythera mechanism, scholar Derek de Solla
Price felt it was the clue with which he could...
before their college days at Parvoo U., our two amateur electronics sleuthing buddies
were on the job tracking down and trapping bad guys by using their combined knowledge
of circuits and physics. In this episode,
Carl and Jerry are tasked with helping a hobby store owner stop
a rash of thefts that always seems to occur during a busy time right after school
lets out for the day. Their first inclination was to devise a system like the big
department stores were installing that used passive tags on items that would trigger
everything RF has updated its Cable Assembly Builder
tool to help users get quotations from over 25 manufacturers at one go. Users can
specify their requirement and select the manufacturers from whom they would like
to get a quotation. The tool has been optimized for mobiles, tablets and desktops
allowing users to access this from anywhere.
Try it out.
In the 1930s, electricity and
electronics were mysteries to most of the population. The concepts were relatively
new and few had a firm grasp on the technology. That reality was exploited by Hugo
Gernsback during the 1934 Electrical Exposition to challenge attendees to discover
how the radio receiver sitting on the top of an empty, clear glass case was being
powered. It was
a clever ruse that reportedly stumped most people. The secret
is revealed here. BTW, my guess is that an even smaller proportion of our current
citizens would be able to figure it out, or for that matter
Empower RF Systems is
looking for an Applications Engineer. Key responsibilities and deliverables include:
Partner with sales, engineering, business development, and executive management
to identify and close on power amplifier solutions for key markets and customers.
Provides sales personnel with technical support for the promotion and positioning
of existing and new products. Responsible for inputs to marketing plans, development
of sales tools, and selected, web content preparation. Provides customer feedback
to improve existing products
Electronics, a manufacturer of RF and microwave filters, has published its September
2014 newsletter. As always, it includes both company news and some tidbits about
relevant industry events, regulations, and standards. This month, Sam Benzacar offers
his views on the subject of "Interference to Defense Systems: Tough Challenges Require
Unique Solutions." There are also a couple headlines on an iPhone-based radar app,
military small cell spending, and stealth wind turbines.
a booster we can increase that capability on the order of one to the fourth power."
- Captain James T. Kirk, Commander of the Star Ship Enterprise. While Melanie and
I were watching the Star Trek original television series episode titled
"Court Martial," I picked up on a funny
technical faux pas. Kirk is accused of the negligent death of
a crew member with whom he has had a longtime difficult relationship. Believing
that the man is faking his own death to incriminate him, Capt. Kirk has the ship's
auditory sensors boosted...