See Page 1 |
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4 of the October 2021 homepage
archives.
Thursday the 21st
Dealing with on-site traveling salesmen has
always been a sort of love-hate (or maybe a necessary evil, to put it less extremely)
relationship - for both the salesman and the engineer/technician. Not having been
in the engineering design environment for nearly two decades, I don't know how much
face-to-face contact is made anymore. Up through the early 2000s, I was still occasionally
meeting with components salesmen. In this June 1952 issue of Radio & Television
News magazine's
Mac's Radio Service Shop technodrama, proprietor Mac McGregor takes the occasion
of an afternoon rain torrent to discuss the situation with two of his regular sales
representatives. The open trading of pet peeves and appreciated behavior on both
sides is common sense stuff, but are courtesies often forgotten while in the throes
of the daily work grind. Mac references a book...
"A coalition of 19 smaller U.S. carriers
are calling on the
Federal Communications Commission to move on scheduling a spectrum auction for
licenses in the 2.5 GHz band, saying it’s a critical opportunity for rural and underserved
areas. The service providers, all members of the Competitive Carriers Association
(CCA), sent an October 11 letter (PDF) to Acting Chairwoman Jessica Rosenworel that
urges the regulator to immediately set an auction date for the more than 8,000 mid-band
licenses in its inventory. C Spire, GCI Communications, Union Wireless, Carolina
West, Viaero Wireless, and Nex-Tech Wireless are among some of the signatories..."
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.
Navy Electricity and Electronics Training
Series (NEETS) Module 4 -
Introduction
to Electrical Conductors, Wiring Techniques, and Schematic Reading. Upon completing
this chapter, you should be able to: 1. Recall the definitions of unit size, mil-foot,
square mil, and circular mil and the mathematical equations and calculations for
each. 2. Define specific resistance and recall the three factors used to calculate
it in ohms. 3. Describe the proper use of the American Wire Gauge when making wire
measurements. 4. Recall the factors required in selecting proper size wire. 5. State
the advantages and disadvantages of copper or aluminum as conductors. 6. Define
insulation resistance and dielectric strength including how the dielectric strength
of an insulator is determined. 7. Identify the safety precautions to be taken when
working with insulating materials...
Even though this CW (continuous wave, for
sending Morse code)
transmitter circuit was published in 1955 in Popular Electronics magazine,
it is still legal for today's Amateur radio operator. Portions of the 40-meter and
80-meter bands are still reserved exclusively for CW operation. As of 2021, the
40-meter band (7.025-7.125 MHz) and the 80-meter band (3.525-3.600 MHz)
are both reserved for CW for Hams holding either Novice (no longer issued) or Technician
licenses. Additionally, the 15-meter band (21.025-21.200 MHz) and the 2-meter
band (144.0-144.1 MHz) have CW-only areas. That is different than the frequencies
given in the article, so beware if you are tempted to throw one together for old
time's sake. The value for XTAL will need...
Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
Wednesday the 20th
In this 1946 issue of Radio-Craft
magazine, editor and über electronics guru Hugo Gernsback reviews "Secret
Communications" methods used throughout history, including Alexander Graham
Bell's "Photophone" that used a modulated light beam for transmission. With World
War II having recently ended and devices such as the "Enigma Machine" developed
by the Germans for secure encryption of messages, secure communications was high
on the priority list of government and military strategists. Gernsback also suggests
ultrasonic systems for wireless communications, and a multiple channel scheme suggestive
of the m-ary method widely used today...
"Can
a small wireless power startup really use its 'RF
Holography' technology to charge personal electronics from several meters away,
without irradiating their users? Join ED's Lee Goldberg as he takes a deep dive
into the theory behind the system. Our recent story 'Wireless Power System Approved
by EU and UK Claims to Charge Mobile Devices Without Frying Users' caused quite
a stir amongst our loyal reader community. In fact, more of our sharp-eyed readers
took the time to weigh in on the technology's relative merits than any other story
I've written in the last decade (or two). Nearly all of their responses were even
more skeptical than I was of Ossia's claims to be able to deliver meaningful amounts
of power to devices multiple meters away via either 2.4- or 5.8-GHz RF beams..."
This was a multi-part series published by
Radio & Television News magazine in the days when
color TV was the domain of the more well-to-do folks on the block. Needless
to say (but I'll say it anyway), nobody I knew had color TV before around 1968.
One of my friend's father owned a fairly profitable gas station and service garage,
so they were the first to have one. For some inexplicable reason (I jest), his mother
never allowed more than one or two of us into the house at a time, so we drew straws
to see who got to witness that fabled miracle of technology. I was about third in
line. Insomuch as the 1960s were a much more polite and private time than the present,
peeking through a living room window for a preview was expressly verboten. In fact,
going into a friend's house for any reason was rare. The privileged appointments
were strictly adhered...
ConductRF FPA Cable Assemblies use a unique,
Low Loss, high performance
Semi-"FlexiForm" Cable that is formable, but flexible, providing system designers
with a versatile solution for High Frequency applications. The product also allows
for very tight phase matching to ±0.2º. Available in three common cable diameters,
with the benefits of higher operating frequencies, shielding effectiveness and stability
performance over traditional standard Hand Formable cables, these solutions enhance
any application requiring higher performance. ConductRF's FPA Cable Assemblies are
manufactured using the latest induction soldering techniques to best ensure the
highest quality and performance...
Thanks to a tip by RF Cafe visitor and contributor
Bob Davis for letting me know about a very capable point-to-point
RF system planner called Radio Mobile (URL updated since original expired),
by Canadian Ham radio operator Roger Coudé (VE2DBE). There is another similar freeware
program available called AlphiMax, but it requires that you upload your system data
to a remote server - a potential confidentiality conflict. Radio Mobile uses GPS-based
terrain information obtained from the U.S. Department of Commerce NTIA/ITS Institute
for Telecommunication Sciences Irregular Terrain Model (ITM) database...
RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable job openings. HR department employees and/or
managers of hiring companies are welcome to submit opportunities for posting at
no charge (of course a gratuity will be graciously accepted). 3rd party recruiters
and temp agencies are not included so as to assure a high quality of listings. Please
read through the easy procedure to benefit from RF Cafe's high quality visitors ...
SF Circuits' specialty is in the complex,
advanced technology of PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
Tuesday the 19th
Although not directly applicable today, these
charts from a 1952 issue of Radio & Television News magazine showing
signal voltage levels versus distance from broadcast television transmitter
locations provide a general sense of how attenuation varies as a function of distance.
Both low (channels 2-6 at 54-88 MHz) and high (channels 7-13 at 174-216 MHz)
VHF bands are included for a couple different standard power levels. A Transvision
Model FSM-1 field strength meter (see example at left) was used to construct these
charts. While the Friis equation for signal free space attenuation can be used to
predict levels, actual physical measurements are often more useful in real-world
scenarios where landscape and manmade obstructions...
Here is an easy-to-build project that demonstrates
how like electrical charges repel. The
electroscope was developed by English physicist William Gilbert in 1600. I remember
playing with one in physics class in junior high school (one of the few classes
that interested me at the time). The electroscope in this 1955 Popular Electronics
magazine article calls for the use of gold leaf, but it can be any type of good
electrical conductor. In fact, I found a video on YouTube that shows how to make
an electroscope out of commonly available materials. This would make a good conversation
piece to sit on your desk...
Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners
(hence 'Triad') with over 40 years of accumulated
knowledge of what is required to design, manufacture, market, sell and service RF/Microwave
amplifiers and amplifier systems. PA, LNA, bi-directional, and frequency translating
amplifiers are available, in formats including tower mount, benchtop, rack mount,
and chassis mount. "We view Triad more as a technology partner than a vendor for
our line-of-sight communications product line." Please check to see how they can
help your project.
"With the popularity of GPS, location is
becoming an important feature for wireless devices. Now, consumers want
micro-location, and, in turn, wireless technologies are adapting to it and accuracy
levels are on the rise. Using wireless technologies for positioning isn't new. However,
the level of accuracy required has evolved over the years upon identification of
new location-based use cases. A GPS system, for example, can achieve roughly between
a 5- to 20-meter level of accuracy, depending on signal conditions. This is sufficient
when driving around to locate a particular building, but a GPS level of accuracy
can't meet the needs of finding, say, a specific shelf in a store or point to the
right painting in a museum tour..."
I have been scanning and posting many "Radio
Service Data Sheets" like this one featuring the
Arvin Model 6 under-dash car radio in graphical format, but have not yet
run OCR on them to reproduce the textual content for search purposes. Radio-Craft
magazine and others published many of these for the sake of hobbyists and commercial
repair shops that could not afford to pay for subscriptions to services such as
Sams Photofact. I could not locate an example of a restored model. Manufacturers
usually would not provide service data to non-representatives. 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...
This is another Radio Service Data Sheet
that appeared in the March 1936 edition of Radio-Craft magazine. I post
this schematic and functional description of the
Belmont Model 578 Series A, 5-Tube A.C. Superheterodyne radio manufacturers'
publications for the benefit of hobbyists and archivists who might be searching
for such information either in a effort to restore a radio to working condition,
or to collect archival information...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 16,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content is
added on a daily basis, which keeps the major search engines interested enough to
spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
Alliance Test Equipment sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
Monday the 18th
Have you noticed how
heavily burdened utility poles (formerly referred to as electric poles or telephone
poles) are these days? Many of the decades-old creosoted wooden poles originally
were designed to carry a single set of high voltage distribution lines (13.8 kV)
and a multiconductor telephone cable containing twisted pairs. Look around now and
you will see at least twice that number of cables, and often three times as many
due to multiple coaxial and fiber optic cables and needing to route extra AC power
circuits (of larger gauge to handle higher current) in increasingly crowded areas.
Notice how many are leaning over (particularly at corners) and/or are being supported
with additional guy cables and/or splints. Half a century ago when music, talk,
and television was broadcast over the air, the need to string wire all over the
landscape was not necessary. Some people complained about "ugly" TV and radio station
broadcast antennas...
Here is Part 4 of Machine Design
magazine's "Engineering
Your Career: Networking and Being Mentored" series. Author Tricia Hatley begins:
"Career advancements come to engineers through the support of many others. What
does career success mean to you? For some, it is being highly compensated and able
to comfortably take care of yourself and family. For others, it means power and
control. It could also mean continuing the legacy of a family business. Many engineers
and technical professionals define success as working on challenging projects and
creating technical innovations or being considered a technical expert. You may have
an entrepreneurial mindset, so success could be building a new business or service
line..."
Probably when you think about vacuum tubes,
you envision the short type that plugged into your (or your parent's) TV set or
radio. While they were sophisticated in their own way and also required careful
assembly with a lot of manual operations, these high power tubes were in a class
of their own. Even the one in this article from the April 1959 Popular Electronics
magazine is not as complicated as some of the ones designed and built for high power
radar systems. As always, it is interesting to note the lack of eye protection during
assembly operations, especially given that the glass could easily shatter at any
point. I'm guessing that the guy in Figure 1, doing the glass shaping operation
over a hot flame, only has on glasses because he happens to need them to see...
A controversy brews over the merits of breeding
plants that glow like a lightning bug. Proponents say
glowing
trees could eventually replace electric street lights, thereby reducing pollution
created by generating stations. Opponents say messing around with tree genes is
dangerous and should be disallowed since it could lead to unanticipated environmental
ramifications on both plant and animal species. The unique aspect of this effort
is that it is being pursued primarily by genetic hobbyists rather than corporations
- at least for now. There is bound to be a huge financial potential for such a copyrighted
line of plants. My opposition to the concept is primarily a concern for light pollution
projected skyward. Astronomers have a difficult enough time with ever-encroaching
sources of ambient light...
The drone, aka Remotely Piloted Vehicle (RPV)
and
Unmanned Aerial System (UAS), has been mainstreamed in the last few years. Although
drones have been around since the end of World War I, in use for target practice
and eventually for reconnaissance, they have evolved from fairly crude platforms
that require intensive human interaction to fully autonomous systems that can be
programmed with a full mission profile then launched, modified for mission changes
en route and in situ if necessary, and finally retrieved and reused. GPS,
inertial guidance (gyroscopes), radar, lidar, and other complex sensors allow the
craft to monitor and correct its flight course and attitude. For many dangerous
missions - especially highly dangerous ones - drones have virtually eliminated the
need to have a human pilot in the cockpit...
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...
RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
Sunday the 17th
China test-fired a new missile with
a hypersonic glide vehicle capable of delivering a nuclear warhead anywhere
on Earth. It supposedly "caught U.S. military officials by surprise." Evidently
the Chinese general whom "woke"
General Milley called in January to promise he'd let him know if Trump was going
to do anything bad didn't return the favor of advance notice. Add to that the billions
of $$$ worth of state-of-the-art weapons left for the
Taliban in Afghanistan for their use and China and Russia to reverse engineer.
Oh, and our open southern border is being rushed by tens of thousands of people
of unknown origin (although some we know are terrorists), with cartels battling
border agents using powerful weapons. Meanwhile, police back home are being demonized
and "defunded" and the parents speaking out at school board meetings are called
"domestic
terrorists." Ah, what a wonderful world.
This
Radio
Theme Crossword Puzzle for June 13 has many words and clues related to RF, microwave,
and mm-wave engineering, optics, mathematics, chemistry, physics, and other technical
subjects. As always, this crossword contains no names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort unless it/he/she is
related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska
event in Siberia). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!

Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
Friday the 15th
As usual, "getting" the message in some
of these vintage
electronics-themed comics requires at least a passing familiarity with the state
of technology and public mindset of the day. However, in most cases appreciating
the humor and/or irony is possible without it. This group of six comics appeared
in a 1953 issue of Radio-Electronics magazine. The first comic is a good example
of needing some insider information. Back when commercial television was broadcast
over the air from giant towers, multipath of the signal, particularly in urban areas,
often created a situation where the difference in arrival time of the signal at
the TV viewer's location caused more than one version of the picture to be displayed,
slightly offset from each other...
"Equiangular
lines are lines in space that pass through a single point, and whose pairwise
angles are all equal. Picture in 2D the three diagonals of a regular hexagon, and
in 3D, the six lines connecting opposite vertices of a regular icosahedron. Mathematicians
are not limited to three dimensions, however. 'In high dimensions, things really
get interesting, and the possibilities can seem limitless,' says Yufei Zhao, assistant
professor of mathematics. But they aren't limitless, according to Zhao and his team
of MIT mathematicians, who sought to solve this problem on the geometry of lines
in high-dimensional space. It's a problem that researchers have been puzzling over
for at least 70 years..."
"With global 5G networks providing new enhanced
technical capabilities serving over 429 million connections, modern industries are
examining how 5G wireless cellular connectivity impacts their businesses. 5G Americas
has now announced the publication of a new white paper entitled '5G
Vertical Use Cases' which provides a deep dive into the benefits, opportunities,
and requirements for enterprise adoption of 5G. Said Chris Pearson, President of
5G Americas, 'The 5G architecture allows for innovation. In 2021, the world approaches
200 5G networks and millions of connected 5G devices. Entities are thinking hard
about what the faster data rates, lower latency, and precision management of connected
sensors and devices..."
Each
year the Foundational Questions Institute (FQXi) holds an essay contest inviting
writers to submit missives addressing the question chosen by the FQXi board as being
particularly thought-provoking. In their words, "FQXi catalyzes, supports, and disseminates
research on questions at the foundations of physics and cosmology, particularly
new frontiers and innovative ideas integral to a deep understanding of reality,
but unlikely to be supported by conventional funding sources." The 2011 question
was "Is Reality
Digital or Analog?" (here is The Wayback Machine's capture of the original webpage).
Scientific American magazine, being one of three partners, published the runner-up
entry in the December 2012 issue: University of Cambridge professor of theoretical
physics...
Our president and other pontificating politicians
- particularly, it seems, those who hold college degrees in non-science realms -
have recently taken to referring to anyone who does not hold their points of view
as "Flat Earthers" and anti-science.
BTW, these are the same people who regularly chastise their opponents for name-calling
and uncivil discourse. So, if to them others are anti-science, then they obviously
deem themselves to be pro-science. Would you consider a person who laments the invention
of the ATM machine because it replaces bank tellers or a ticket kiosk at the airport
for robbing counter clerks pro- or anti-science? What about people who prefer to
cripple society with a blinders-on approach to energy production by insisting on
using "renewable" sources while ignoring advances in fossil and nuclear power sources?
Excuse me for getting all sciency[sic] on them...
We have all seen news reports about the often
exorbitant
salaries
of government employees as compared to the earnings of folks in equivalent private
sector jobs. According to a March 2012 report by the Bureau of Labor Statistics,
the average total compensation for the average private industry worker was $28.57
per hour worked whereas for the federal government worker it was $40.90 per hour
- a 43% difference! When you look at the ranges of job titles and pay for government
workers as compared to equivalent private industry workers there seems to be no
logical correlation between which jobs pay more with the government versus private
industry. There are currently about 22 million U.S. government employees - a staggering
number indeed. Asbury Park Press recently made available a database (not available
anymore...
"The Congress shall have Power … To promote
the Progress of Science and useful Arts, by securing for limited Tımes to Authors
and Inventors the exclusive
Right
to their respective Writings and Discoveries." - United States Constitution,
Article I, Section 8. Therein lies the authority for legislation and prosecution
of rights for virtually every human creation within the jurisdiction of the country.
Each nation has it own version, and international agreements help assure universal
protection of a creator's rights of ownership; e.g., the "Convention for the Protection
of Literary and Artistic Works" (aka the "Berne Convention") of 1886 and the World
Intellectual Property Organization (WIPO). America has the U.S. Copyright Office.
Those of us involved in presenting information and referring to legally protected
works of others are, or should be, concerned with laws governing how such content
may be used...
I have often said that some of the most capable
and enthusiastic engineers and technicians - and even managers - I have worked with
in my 30-something year electronics career have been amateur radio operators. They
are the rare few who are able to combine a hobby passion with a profession that
pays for the hobby... kind of like the airline pilot who flies model airplanes or
the druggie who works at a pharmacy. Oh, wait, scratch that last example. Here we
see a video from Chevrolet where two engineers, one of them a Ham, took up the challenge
to replace the
AM/FM whip
antenna originally planned for the 2011 Camaro convertible with a blended, inconspicuous
antenna. Leaked photos of the prototype car showed the whip, which caused Camaro
aficionados to descend upon Chevy requesting its removal. The flexible, folding
rear window prevented...
Space Shuttle Endeavour (named after the
ship of British Lt. James Cook) lifts off for the last time tomorrow (April 29).
Atlantis flies next month, marking the end of the USA's manned space flight vehicle
program for the foreseeable future. Henceforth, we will be hitching rides on Chinese
and Russian craft that still land in the desert using parachutes. Here are some
stats on the Shuttle program. Number of shuttles: 5 - Challenger, Discovery, Atlantis,
Endeavour, Columbia; expected launches: 500; actual: 135; total flight time (as
of Jan 2011): 1289 days; shuttles lost: 2 (Challenger, Columbia); total passengers:
836; failure rate: 1:67.5; fuel consumption rate: 660,000 lbs./min. solid, 45,000
gpm liquid hydrogen; 17,000 gpm LOX; time to orbit: 8.5 min.; orbital speed: 17,
500 mph; touchdown speed: 220 mph. As with our oil drilling industry, politicians
have chosen to trash our domestic space transportation industry and send that money
to countries that yearn for our demise...
Qorvo's Design Summit Webinar Series is back.
Qorvo's 2020 Design Summit webinars received over 10,000 views. This series of webinars,
running November 9, 10, and 11, explores the RF and power technology driving markets
for 5G handsets and base stations, defense and aerospace, connected cars and homes
and more. Broadcast times are 11 am, 1 pm, 3 pm and 5 pm Eastern. Topics include:
GaN Solutions for Defense & Aerospace Applications, UWB for Automotive: An Engineering
Primer, Antenna Solutions Reimagined, and Wi-Fi 6 / 6E: How 6 GHz and Matter Will
Change the Smart Home...
With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols available for RF, analog, and digital system and schematic
drawings! Every object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Symbols are provided
for equipment racks and test equipment, system block diagrams, conceptual drawings,
and schematics. Unlike previous versions, these are NOT Stencils, but instead are
all contained on tabbed pages within a single Visio document. That puts everything
in front of you in its full glory. Just copy and paste what you need on your drawing.
The file format is XML so everything plays nicely with Visio 2013 and later...
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms
are available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
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.
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