The inventions and products featured on these pages were chosen either for their uniqueness in the RF engineering realm, or are simply awesome
(or ridiculous) enough to warrant an appearance.
All Featured Product Archive Pages:
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3 | 4 | 5 |
6 | 7 | 8 |
9 | 10 | 11
| 12 | | 13 | 14
| 15 | 16 | 17
| 18 | 19 | 20
| 21 |
 A couple days ago I posted an update on the Watkins-Johnson
databook page that had an unauthorized gag graph titled, "WJ-G1/SMG1 Phase vs. VCTL vs.
Frequency vs. Phase of the Moon." When RF Cafe visitor and sometimes contributor Dr. Marek
Klemes* read that, he sent me a note about remembering this
"Delayed Light Turn-Off"
circuit from the Signetics 555/556 Timer Databook. It took a bit of creative Googling,
but he managed to find the datasheet (to the right). The text was a bit washed out from
the original low resolution scan, so I reproduced the labels (green). This Rube Goldberg-ish
contraption works thusly: After a delay determined by the values selected for R1
and C1, the output of the NE555 timer goes high and causes resistor RL
to heat up enough to ignite match M1. M1 subsequently lights the
fuse on firecracker FC1, which has tied to its body a string that wraps around
a pulley and holds a rock (which weighs precisely 2π pounds ...
12/7/2018
Longtime RF Cafe visitor, electrical engineer, and occasional contributor Alan Dewey
sent me a note yesterday saying a book for which he helped provide a large amount of
research data has been published by authors Iain Dey and Douglas Buck. "The Cryotron Files: How the Inventor
of the Microchip Put Himself in the KGB's Sights," is an extensive delve into the
background of Dr. Dudley Allen Buck, whose son, Douglas, conducted an extensive
investigation into his father's mysterious death that happened to coincide with the death
of his colleague and two other scientists just days after being visited by Soviet computer
experts. Dr. Buck was a superconductivity researcher during his short, highly productive
life. A cryotron, BTW, is a superconducting switch that would make for very low power
supercomputers if it could be made practical in IC form ...
11/20/2018
 An advertisement for Mini-Circuits' DIY
Vector Network Analyzer Kit
appeared in the October issue of Microwaves & RF magazine. It is evidently the
first of a planned series of University Projects. Billed as an attempt to "Bridge the
gap between textbook theory and real-world measurement," Project No. 1-UVNA-63 targets
college laboratories as low-cost means of procuring a high performance vector network
analyzer (VNA) at a reasonable cost ($2,495.00). The frequency range is 100 MHz
to 6 GHz. Having the student build the 1-UVNA-63 provides a familiarity with a block
diagram level understanding of 2-port VNAs and gives hands-on experience with assembling
RF components. Included are filters, directional couplers, a transceiver PCB (made by
Vayyar) ...
11/1/2018
 Take a look at this
ARRA (Antenna & Radome Research
Associates) attenuator advertisement that appeared in the September 2018 issue of
Microwaves & RF magazine a tell me if it reminds you of something
you might have seen in the 1960's through 1980's. That might not have been the intention,
but seeing it sure triggered my nostalgia mechanism. Even the tag line, "When it comes
to attenuators, nobody - but nobody - can fill our shoes," idiom, being somewhat dated,
conjures up memories of vintage company slogans. Of course the black and white format
feeds the perception. Maybe I'm wrong, but if it appeals to me for any reason, the ad
designers have done their job ...
10/9/2018
 Rohde & Schwarz has been publishing a series
of good old-fashioned printed (aka hard copy) Pocket Guides on RF test and measurement
topics. This latest one titled, "Key Characteristics
of Signal Generators and Modulation Methods: Pocket Guide," arrived in my mailbox
(the physical one at the curb, not Outlook). There are 116 pages chock full of an amazing
amount of descriptions, equations, tables, and graphs. The main topic areas are analog,
vector, and arbitrary (ARB) waveform generators, and analog and digital modulation methods.
It also reviews associated topics like phase noise, VSWR, intercept points, etc. A sampling
of them are reproduced below. You can get your own free copy by filling out the form
on the R&S website ...
10/8/2018
 Sitting in the waiting room in the local Jeep dealership,
waiting for the technicians to do the annual inspection on the 2011 Patriot, I noticed
a 12 volt car battery sitting on a table. At first I assumed it was just a sales pitch
for a new battery, but then I noticed a bunch of small cables coming from its bottom
edge. As you can see in the photo I took of it, those cables are mobile device charging
cords with mating connectors for Apple, USB, and miniUSB ports. An Internet search did
not turn up any of these things, so maybe Mopar engineers came up with it. Times sure
have changed from when ...
6/18/2018
 Rohde & Schwarz is offering at no cost a variety
of reference charts (posters) for hanging on your lab or office wall, and some handy-dandy
Pocket Guides. In the current
age of (seemingly) paperless offices and laboratories, opening a cardboard package from
R&S containing the pictured items caused me to wax nostalgic over the days when sales
reps handed out such materials during workplace meetings and at trade shows. Wall charts
are still fairly easily obtained, but the spiral-bound pocket guides are more rare. Maybe
soon we'll be seeing the resurrection of cardboard slide rule calculators ...
3/14/2018
 Mr. Oleg Sakharov, Director of the Center of Telecom.
Technologies, LLC, recently sent me information on the
MLinkPlanner software for performing microwave communications link design. Judging
only from the provided screenshots and the online documentation, MLinkPlanner looks to
be very user friendly and loaded with features. I downloaded the 7-day free trial and
did a quick fictitious link between my house in Erie, PA, and the WBEN AM radio station
in Buffalo, NY. My route is mostly over Lake Erie, so there was not much in the way of
obstructions, other than the curvature of the earth ...
12/18/2017
 Hyperlinks all around the Internet pointing to
Hittite's infamous Mixer Spurious Product Calculator broke suddenly when Analog Devices
swallowed up Hittite in 2014. The good news is that if you still want to use it, you
can find it as the ADI Mixer-Spur Graphical Representation tool on the ADI website. However,
Marki Microwave now has a much nicer
Spur Calculator that you will want to consider. It provides both a Spur Web format
and a Spectrum Analyzer format for presenting mixer spurious products. The interface
is very user friendly both for the input and the output specification. The Spur Web screen
uses a format pioneered ...
12/1/2017
 QuickSmith, a creation of Nathan Iyer, has been
around for a long time. It is without a doubt one of the most feature-filled examples
of RF design software around. Nathan recently released a Web-based version of QuickSmith
on a GitHub server, which means it works on any platform with a browser - desktop or
mobile. Access is free, and you can save and reload your design files rather than losing
your work once you leave the website. Being online also means that the latest version
is always available. The screenshot to the right illustrates where to place series and
parallel components, and where to access the sweep ...
8/30/2017
 You might think the world doesn't need another
RF basics book, but the fact is there are so many new people coming into the field that
there is always room for one more - particular a well-done edition like "RF Basics
Handbook" from Rigol Technologies. The PDF download is free, but you do need to fill
out a submission form. A replication of the table of contents give you an idea of all
the topics covered. The photos and drawings are very good quality. Of course the equipment
used in the publication are representative of Rigol's product line, but that's to be
expected ...
8/15/2017
 Amateur radio operators take note: Heathkit, which
in years past was a prime supplier of homebuilt ham radio gear, has just announced plans
to manufacture its first piece of test equipment in three decades. "Now there's the Heathkit®
HM-1002: Intuitive, intelligent, affordable, accurate measurement. The next-generation
Heathkit® HM-1002 Precision RF Meter™ picks up where our
venerable SWR / wattmeters of yesteryear -- and everyone else's -- stopped. Incredible
new features, yet simple for beginners to assemble and understand. And you can build
and maintain it yourself." ...
6/26/2017
 Dr. Andrei Muller, progenitor of the world's
first 3D Smith Chart software program,
has teamed with a handful of able colleagues to release this commercial version of this
paradigm-changing design and analysis tool. 3D Smith Chart enables you to visualize
S-parameter data in ways not possible from the Flatland dweller's perspective that is
the traditional 2D Smith chart. Flatland existed in a plane, and from an observer's
perspective a 3-dimensional object entering the plane from along the Z-axis seemed to
appear out of nowhere ...
5/22/2017
 This back-page advertisement by
Model Rectifier Corporation (aka MRC)
appeared in the January 1972 issue of American Aircraft Modeler magazine. Note
the cool collection of [now] vintage test equipment shown
in support of testing the R/C system. The advertisement shows a rhombic antenna, the
Dana 8015 RF frequency counter, Tektronix 7904 oscilloscope, HP spectrum analyzer, RF
communications synthesizer RF generator, Anritsu precision field strength meter. I was
13 years old at the time, and anxiously watched for in the mailbox each month ...
4/17/2017
 RF Cafe visitor Tony C., who is an engineer
working for on of America's great, longtime manufacturers of green farm equipment, sent
me a link to this unique memory IC released by Signetics on April 1, 1973. Being April
1, 2017, it seems to be an appropriate day to post the Signetics 25120 Fully Encoded,
9046 x N, Random access Write-Only Memory datasheet that per Wikipedia, "...was created
'as a lark' by Signetics engineer John G 'Jack' Curtis and was inspired by a fictitious
and humorous vacuum tube datasheet from ..."
April 1, 2017
 How many times have you dug through a drawer of
coaxial connector adapters and found what seemed
like every possible combination of TNCs, Ns, SMAs, TNCs, UHFs, SMBs, and
<fill in the blank>s except the one you really need?
Sometimes the reason is simply because all on hand are being used for something else
and cannot be 'borrowed' for your use. Other times it is because the need never existed
before. Usually, a quick search on the Internet will turn up exactly want you want, but
for decent a quality adapter you will pay a stiff price - especially if it is a rare
combination of connector types. The truth is, not often is a combination like QMA-Male-Right-Angle-to-TNC-Female-Bulkhead
adapter or ...
7/15/2016
 Just as the paperless office, predicted to quickly
become a reality when personal computers were beginning to dominate the workplace and
home in the 1980s, has yet to occur, neither has desktop software for high-end applications
totally replaced online equivalents. Microsoft has made good progress in the last few
years in moving part of their Office suite online, you still need a local copy of Visio,
Project, and even their Visual Studio software development tools if you want to use them.
Graphics and video editing software cannot be used efficiently online. The problem is
mostly due to time latency between user input and software display response. Speed on
the host server end is addressable with pumped up computing power and extra
...
7/7/2016
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