See Page 1 |
2 |
3 |
4 of the November 2019 homepage archives. Friday 29
 Most of us are likely familiar with the ongoing
debate over whether
radiation from cellphones, Wi-Fi routers and laptop computers, cell towers,
smart meters, and other such modern gadgetry is harmful to humans. It is not
ionizing radiation like nuclear decay, but there are heating effects that can
cause damage under the right conditions. One week news breaks from the latest
organization shocking the public with proof of tissue cell damage to brain,
hand, face, eyeball, and groin tissue (from laptops). The next week brings a
counter report refuting apocalyptic claims of previous studies... then the cycle
repeats. Early in the age of ubiquitous wireless devices, those seeking to
mitigate worries of radiation argued - somewhat correctly - that enough time had
not yet passed to collect statistically meaningful data. If significant harm
could be proven right away, dismissing the empirical results...
 A cure for bovine cabin fever -- "If you
walked onto the RusMoloko dairy farm near Moscow, in Russia, you may think you've
arrived onto a bizarre futuristic film set, where cows run around fitted with VR
headsets. The
VR goggles aren't props for a film,
however. They have been specifically made for these dairy cows, so as to improve
their conditions and enable them to relax into producing more milk. Many different
industries around the world are turning more and more toward computerization to
improve working conditions, so why not the farming industry too? These headsets
were carefully designed by combining years of experience in the dairy farming industry,
as well as technology. The pressing issue of milk production led to experts from
the IT world, as well as industry leaders in milk production ..."
 "The perfect squelch" was a popular concept
in the 1950s. I know because I've seen it in a few different magazines from that
era. In fact, The Saturday Evening Post ran a regular inset feature by that name.
As you might guess, it has to do with making a short statement that has the effect
of cutting out the 'noise,' whether it be from the background of a radio reception
or from an obnoxious person shooting off his mouth (which was the case for the SEP).
BTW, the "Squegg" part of
Sunspot McSquegg's name comes from the radio term 'squeg,' which refers to
oscillations due to excessive feedback, like what happens when a microphone is
placed too close to the speaker. This Christmastime tidbit appeared in the
December 1953 issue of QST magazine...
 Exodus Advanced Communications model
AMP2080B-1 high power 10 kHz to 100 MHz amplifier produces 150 W
minimum, and >200 W nominal power. The minimum power gain is >52 dB
with excellent gain flatness. Optionally, Exodus offers monitoring parameters for
forward/reflected power and VSWR, as well as voltage, current and temperature sensing
for optimum reliability & ruggedness for all applications. Nominal weight is
35 lbs, and dimensions of 19"W x 22"L x 5.25"H. Class A/AB linear LDMOS
design Rack mounted system Designed for broadband EMI/RFI, Lab, Communication
applications...
 "Carbonics, Inc., has demonstrated a wafer-scalable
approach for producing an array of aligned
carbon nanotube (CNT) FETs with performance
exceeding 100 GHz and linearity of 10 dB. The firm, based on Los Angeles,
is a spinout from the Center of Excellence for Green Nanotechnologies at UCLA and
King Abdulaziz City for Science and Technology (KACST). Carbonics said this is the
first time carbon nanotube technology has achieved speeds exceeding 100 GHz
in radio frequency (RF) applications. Reported in a paper published this month,
“Wafer-scalable, aligned carbon nanotube transistors operating at frequencies of
over 100 GHz," it added the milestone 'eclipses' the performance - and efficiency
- of traditional RF CMOS technology ..."
Nova Microwave is a leader in technically
differentiated electronic and radio frequency Ferrite
Circulators
and Isolators that connect, protect and control critical commercial and military
wireless telecommunications systems. Our staff is dedicated to research and development
of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz
to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave
product line of is specifically designed for use in varied environmental and temperature
extremes.
Thursday 28
 Mixing a little fun with learning has always
been a good motivation for students. I have written in the past about a particular
electronic circuits professor I had that liked to play practical jokes during lessons
and exams. Including gag options on a multiple choice test is a great way to inject
a bit of tension-easing levity while at the same time eliminating one or more opportunities
to guess at a wrong answer (although no relief for the truly clueless). I sometimes
do that on the RF Cafe Quizzes that I generate. Radio-Craft printed a large
bunch of such quiz questions under the title "Radio
WittiQuiz," where the questions and answers were provided by readers. Here
is one from November 1937...
 "A new technique developed at Harvard speeds
up
multimaterial printing by allowing up
to eight different printing materials to fabricate objects. Harvard University researchers
have engineered a new fabrication method that promises to accelerate a lagging area
of 3D printing technology - multimaterial printing. The technique, called multimaterial
multi-nozzle 3D printing (MM3D), was developed by researchers from Harvard's Wyss
Institute for Biologically Inspired Engineering and John A. Paulson School of Engineering
and Applied Sciences (SEAS). MM3D uses high-speed pressure valves that continuously
and seamlessly switch between up to eight different printing materials at a speed ..."
 Atenlab Corporation has updated their list
of global sales representatives for the company's large variety of
antenna measurement systems. Atenlab has developed four major categories of
Over-the-Air (OTA) measurement systems to meet various requirements - A2 light type,
A3 compact type, A6 standard type and A8 professional type. OTA measurement facilities
are widely used in the communication system and device manufacturing industry. With
the advancement of the OTA measurement system, customers are able to perform more
comprehensive measurement and test, staying ahead in the market. Please contact
one of our representatives today to learn how Atenlab can help your project succeed.
Compact Antenna Test Ranges (CATR) are able to measure up to 100 GHz...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's Matchmakers"
Smith chart design or the "Engineer's Troubleshooting Flow Chart." My "Matchmaker's"
design has been ripped off by other people and used on their products, so please
be sure to purchase only official RF Cafe gear. My markup is only a paltry 50¢
per item - Cafe Press gets the rest of your purchase price. These would make excellent
gifts for husbands, wives, kids, significant others, and for handing out at company
events or as rewards for excellent service. It's a great way to help support RF
Cafe. Thanks.
 Custom MMIC is a
fabless RF and
microwave MMIC designer entrusted by government and defense industry OEMs. Custom
and off-the-shelf products include switches, phase shifters, attenuators, mixers
and multipliers, and low noise, low phase noise, and distributed amplifiers. From
next-generation long range military radar systems, to advanced aerospace and space-qualified
satellite communications, microwave signal chains are being pushed to new limits
- and no one understands this more than Custom MMIC. Please contact Custom MMIC
today to see how they use their modern engineering, testing and packaging facility
to help your project.
Wednesday 27
 Here are a few good soldering tips that appeared
in a 1973 issue of Popular Electronics magazine. One suggests using hot
melt glue to hold components and cables in place both for soldering and just to
keep them from moving during normal use. Another describes how to turn a standard
pistol type soldering gun into a
resistance soldering tool. It actually works pretty well for soldering sheet
brass and copper, but do keep in mind that there is a live voltage between the two
sections of wire when they are not making contact with the work piece. There's also
a recommended method of soldering stranded or braided wire like coaxial cable shielding
without having so much of the solder wick into the braid beyond where you want it
(another way is to clamp a heatsink on the braid to prevent excess wicking)...
 Anyone who watched the
WKRP in Cincinnati
sitcom back in the 1970s has to remember what was one of the funniest episodes ever.
Here is the 4 minutes that made Prime Time history. In this Thanksgiving episode,
station owner Arthur Carlson decided he would surprise the community with good deed
- that doubled as a promotional stunt for his radio station - by dropping turkeys
from a helicopter for lucky shoppers at the local shopping mall. Watch the disaster
unfold as Les Nessman reports live, and then hear Carlson's final comment that
is still used or alluded to in many comic routines. Posting this video is an RF
Cafe tradition. Have a Happy Thanksgiving!...
 I have always been a stickler for creating
neat, orderly arrangements when building any type of circuit assembly. Many moons
ago when starting out as an electrician, I made a point of installing straight runs
of Romex type cable with no twists, evenly spaced staples, and keeping the identification
marking to the outside. Conduit was precisely bent and installed, again with organized
parallel runs and even spacing where possible. Circuit breaker panel wiring looked
like something seen in an Apollo space capsule (ok, I exaggerated a bit here). Electrical
inspectors often complimented my work. Moving on to an electronics career, the habits
carried over when prototyping and even when directing layout for production PCBs
or chassis assemblies, including cabling. The greatest enjoyment I had was when
laying out runs of
waveguide. Standardized manufactured straight...
 Website
visitor Mike M. wrote a few days ago about his freshly repaired
Dilbert candy
dispenser, and then responded to my piece about
Erie Resistor yesterday. In it was mentioned
Bliley Electric, a long-time manufacturer of radio crystals, also located (still)
in Erie. Being a practicing Ham operator working in CW (Morse code), Mike was looking
for a company that would make a small quantity of custom crystals for him. Bliley
passed on the opportunity, so he looked in his home state of New Jersey and contacted
Bomar Crystal Company
(unofficial motto "I gotcha crystals right hee-ya"). They have a minimum order of
$100, but will make custom crystals for you. Bomar's logo has a very vintage look
to it.
Nova Microwave is a leader in technically
differentiated electronic and radio frequency Ferrite
Circulators
and Isolators that connect, protect and control critical commercial and military
wireless telecommunications systems. Our staff is dedicated to research and development
of standard and custom design quality Ferrite Circulators and Isolators from 380 MHz
to 26.5 GHz. Available in single or multi-junction topographies, the Nova Microwave
product line of is specifically designed for use in varied environmental and temperature
extremes.
 "As connected devices such as voice assistants,
security cameras, and smart appliances grow in popularity, the homes and offices
where they are installed become increasingly filled with a dense web of Wi-Fi signals.
A new study from University of Chicago and University of California, Santa Barbara
researchers finds that external attackers can use inexpensive technology to turn
these
ambient signals into motion detectors,
monitoring activity inside a building without being detected themselves. With only
a small, commercially available Wi-Fi receiver, an attacker from outside the target
site can measure the strength of signals emitted from connected devices and monitor
a site remotely for motion, sensing whether a room is occupied ..."
 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.
Tuesday 26
 Once frequency modulation (FM) began making
inroads in the commercial radio broadcast world, it wasn't long until the pundits
were writing eulogies for
amplitude modulation (AM). There was/is no denying the superiority of FM in
terms of both natural (QRN; e.g., lightning, static, arcing contacts) and manmade
(QRM; e.g., another radio) interference, but there was already a large installed
base of AM radio receivers (and broadcast transmitters) that satisfied their owners'
expectations for listening to news, ball games, music, and the well-established
repertoire of drama and comedy shows. FM radios were generally more expensive to
manufacture, operate, and repair than AM - at least early on, especially since typically
FM sets included AM as well. This particular article from a 1944 issue of Radio
News magazine discusses class C amplifiers...
 Spectrum Instrumentation has added six new
Arbitrary Waveform Generators (AWGs) to its recently released M2p.65 xx series
of PCIe cards. The new AWGs extend the product family's capabilities by boosting
the available output range, so that waveforms can be generated with amplitude swings
of up to ±12 V into 1 MΩ or ±6 V into 50 Ω. To achieve
the higher output voltage ranges, the cards have been fitted with additional amplification
and larger cooling plates. This makes the cards a little wider, so that they occupy
two PCIe slots, but they are still just 168 mm in length. The small size allows
them to fit into almost any PC, turning it into a powerful and flexible waveform
generator. The M2p.65xx series AWGs use the latest 16-bit Digital-to-Analog Converters
and feature a fast PCIe x4 interface with up to 700 MByte/s streaming
speed...
 Since I live in Erie, PA, an erstwhile very
industrial, albeit small town, it is always nice to run across information on the
area in my electronics magazines. There are still a few electronics businesses in
Erie, but as with most of the manufacturing from long ago, high tech here is found
mostly on the shelves of Best Buy and not on manufacturing lines. One notable exception
is Bliley Electric Company, maker of crystal oscillators, who was established in
Erie in 1930. Bliley still operates today in a building about two miles from my
house. This advertisement from the December 1958 edition of Popular Electronics
magazine is by
Erie Resistor Company. In doing a Google search, I found a brief history of
the company on a UK website. According to the author, Erie Resistor opened a
division in Yarmouth in 1932. Here is a reference to Erie Resistor Company being
credited for discovering the ferroelectric oxide...
 Stephen Barthelmes and Patrick Sherlock of
Triad RF Systems, and Ken Andrew of Non Line-of-Sight Wireless, published this article
entitled, "Methods to Increase Channel Capacity in
RF Data Links" in Microwave Product Digest. It begins, "As more people
and organizations demand higher data rates to stream high definition (HD) video
for broadcasting, surveillance, or social media applications, the need for capacity
continues to increase for wireless communication systems. In addition, once more
advanced technology such as 4K video becomes mainstream, performance pressure on
the RF data link for mobile applications will increase to a point where current
technology cannot provide acceptable performance. Applications include handheld
devices (4G/LTE, 5G), as well as conventional and unmanned vehicles ..."
 "In response to recent threats of rogue and
errant drones launched against airports and other critical facilities, infrastructure
and events, 34 North Drones, a leading commercial drone service provider, has partnered
with IDS North America to offer and install the
NO-DRONE radar counter drone system
for all government and civilian clients in need of protection. IDS is a leading
software company that designs, develops, and distributes software for air navigation,
security, and the defense sector. The NO-DRONE radar detection system evolved from
a proven and existing military battlefield solution originally tuned to recognize
small objects such as incoming mortar, artillery and rocket fire ..."
 Empower RF Systems is a global leader in
power amplifier solutions. Empower RF Systems is an established and technologically
superior supplier of high power solid state RF & microwave amplifiers. Our offerings
include modules, intelligent rack-mount amplifiers, and multi-function RF Power
Amplifier solutions to 6 GHz in broadband and band specific designs. Output
power combinations range from tens of watts to multi-kilowatts. Unprecedented size,
weight and power reduction of our amplifiers is superior to anything in the market
at similar frequencies and power levels.
Monday 25
 This is the last of a 5-part article by Farron
Dacus, of Longwing Technology,
entitled "Low-Noise Synthesizer Design Examples," appears in the November
issue of Microwaves & RF magazine. It begins: "In the final chapter
of this 5-part series, we'll look at five different synthesizer designs, comparing
fully integrated synthesizers to discrete implementations. Part 1 introduced higher-order
phase-locked-loop (PLL) design, while Part 2 reviewed noise sources. Part 3 analyzed
noise shaping in the loop followed by Part 4, which presented commercially available
parts for the low-noise PLL designer. This final article is intended to focus on
the noise-performance results and tradeoffs in design examples using the low-noise
techniques and parts presented earlier. Here, we compare the best performance available
with fully integrated synthesizers ..."
 Axiom Test Equipment, an electronic test
equipment rentals and sales company headquartered in North County San Diego, currently
has the need for an
Electronic Repair and Calibration Technician.. General Description: Service
of Axiom owned electronic test equipment by performing: Calibration, installation
of options, troubleshooting, refurbishing, repair and maintenance. Assist salespeople,
customers and management on technical matters and equipment operation, setup and
recommendations. Key Responsibilities: Functional test and inspection of equipment
(purchases, rental returns and RMA returns) for proper operation and evidence of
misuse, and damage. Ensures proper procedures are used to test and calibrate equipment
according to manufacturer specifications...
Res-Net Microwave has a complete line of
precision RF & microwave components including attenuators,
terminations, resistors, and diode detectors for commercial, military, and space
applications. Products range from the small flange type to large 2,000 watt connectorized
power attenuators and/or terminations at frequencies up to 26.5 GHz. In-house
photo etch and laser trim capability. The company is a leader in development and
production of the films required for these type of RF/microwave components. Please
check out Res-Net Microwave's website to see how they can help with your current
project.
 Sometimes, component datasheets can be pathetically
lacking in detail for parameters that you might think would be a minimum amount
of information needed in order to integrate the device into a circuit or system.
Or, it may be that you found a part in a spare parts box and can't find a datasheet
for it. When those times come, it is necessary to characterize the part yourself.
Relay control really isn't rocket science when it comes to electrical
circuits, but there are a few rules of thumb that should always be observed, the
most important of which (other than not exceeding voltage and current maximums)
is to wire a diode reverse biased across the coil terminals so that the
voltage/current induced due to the field collapse during de-energizing does not
smoke the driver circuit...
 The first CES
(Consumer Electronics Show) took place in New York City in June 1967, making this
the 54th occurrence. CES 2020
it will be held in Las Vegas from January 7th through the 10th. "CES is the world's
gathering place for all those who thrive on the business of consumer technologies.
It has served as the proving ground for innovators and breakthrough technologies
for 50 years - the global stage where next-generation innovations are introduced
to the marketplace. CES showcases more than 4,500 exhibiting companies, including
manufacturers, developers and suppliers of consumer technology hardware, content,
technology delivery systems and more; a conference program with more than 250 conference
sessions and more than 170,000 attendees from 160 countries ..."
 "Plextek-DTS is to develop a
miniature drone radar to detect a hostile
drone in the sky, as well as drone signal jamming technology. Radar has traditionally
been too heavy for small unmanned aerial vehicles (UAVs). Plexteck-DTS has been
awarded two contracts under the £2m (€2.3m) Defence and Security Accelerator (DASA)
competition to develop new capabilities to detect, disrupt, and defeat the hostile
and malicious use of drones. Both contracts build on Plextek's world-leading research
and experience in Low Size Weight and Power (SWaP) radio systems. The first project
focuses on the development of an innovative signal detection and jamming capability
to detect and defeat hostile ..."
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave filters for military and commercial communication
systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters,
and RF products. Standard RF filter and cable assembly products are published in
our website database for ease of procurement. Custom RF filters designs are used
when a standard cannot be found, or the requirements dictate a custom approach for
your military and commercial communications needs. Sam Benzacar's monthly newsletters
address contemporary wireless subjects. Please visit Anatech today to see how they
can help your project succeed.
Sunday 24
 For two decades, I have been creating custom
engineering- and science-themed crossword puzzles for the brain-exercising benefit
and pleasure of RF Cafe visitors who are fellow cruciverbalists. This November 24,
2019, puzzle has a holiday message for you. A database of thousands of words is
used which I have built up over the years and contains only clues and terms associated
with engineering, science, physical, astronomy, mathematics, chemistry, etc. You
will never find a word taxing your knowledge of a numbnut soap opera star or the
name of some obscure village in the Andes mountains. You might, however, encounter
the name of a movie star like Hedy Lamarr or a geographical location like
Tunguska, Russia, for reasons which, if you don't already know, might surprise
you. The jury is out on whether or not this type of mental challenge...
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.
Homepage Archive Pages
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
|
