See Page 1 |
2 |
3 |
4 |
5 of the August 2022 homepage archives.
Sunday the 21st
This custom made
Radio Technology theme crossword puzzle from RF Cafe is for August 21st, 2022.
"Down" words consisting of four or more letters begin with the first letter of this
puzzle's theme. All RF Cafe crossword puzzles are custom made by me, Kirt Blattenberger,
and have only words and clues related to RF, microwave, and mm-wave engineering,
optics, mathematics, chemistry, physics, and other technical subjects. As always,
this crossword puzzle 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...
LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
Friday the 19th
If I had the time, it would be interesting
to research how accurate this
Electronic Market prediction from the January issue of Electronics
magazine compares to how the decade actually ended. My guess based on most of the
history of the electronics industry is that except for very fantastic prognostications
of personal nuclear power sources and domestic robots in every household, the forecasts
greatly underestimated actual progress. That is because discoveries are made so
frequently and improvements made so quickly that after ten years there are innumerable
new aspects of electronics that were never even dreamed of a decade earlier. According
to one source, the consumer electronics market in 2020 was close to $700B, as compared
to $1.6B in 1959. Adjusting for inflation, that $1.6B is the equivalent of about
$14B in 2020, so the market growth for consumer electronics in that time period
was around 50x ($700B/$14B). That is a significant increase in just one sector of
the electronics industry...
"A team of Chinese scientists have proposed
sending a fleet of
telescopes to orbit the moon and peek into the most mysterious era of the universe's
past. The Discovering the Sky at the Longest Wavelength (DSL) mission, if officially
approved in the coming weeks, would shed light on the so-called cosmic dark ages,
a time when the infant universe was nothing but a sea of darkness. Astronomers believe
the first stars appeared when the universe was about 200 million years old. Before
that, the world was a rather obscure and empty place: no suns, no planets - only
the hydrogen atoms forged from the Big Bang. Those ancient hydrogen atoms hold the
key to the dark era and the structure of the universe we live in today, but are
impossible to detect from Earth because of interference from human radio activities..."
According to a tally crafted by Radio &
Television News magazine in 1949, the total number of
television sets sold in the United States in 1947 and 1948 was 964,206. There
were approximately 146 million people at the time per the U.S. Census. If there
was an average of 4 people per household, that works out to around one television
set for every 36 houses. Some households already had TV sets during that time, but
far fewer than half owned a television. Nobody owned a color TV then because no
commercial broadcaster used a color camera. Color was still a future feature being
hyped in Mechanix Illustrated and Scientific American, like flying
cars and personal computers. Today, of course, everybody that wants a television
has a television... or two... or three. Effectively, every smartphone and computer
is a TV (via Internet, not direct OTA transmissions) as well. In 1949, almost all
TVs were owned by people who paid for them themselves. Today, many sets are bought
by people who have been subsidized by fellow citizens forced to help pay for them
via tax policies...
For many years I have been scanning and
posting schematics & parts lists like this one featuring the
Atwater Kent Model 305Z 5-Tube 32 V. D.C. Superhet radio. It appeared in a 1936
issue of Radio-Craft magazine. OCR (optical character recognition) software
is run on them to separate the textual content, which allows search engines to capture
words that helps people find information. 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. I keep a running list of all data sheets
at the bottom of the page...
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components
and filters for wireless service providers including non-magnetic connectors for
quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM
RF connectors components such as power dividers and directional couplers. Off-the-shelf
and customized products up to 40 GHz and our low-PIM products can meet -160 dBc
with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and
high-performance. Designs that are cost effective practical and repeatable.
Thursday the 18th
As is the normal modus operandi (MO) of
John T. Frye with his "Carl &
Jerry" series of techno-dramas, this "Too Lucky" episode combines adventure
with electronics to teach a lesson in the process of entertaining with a great story.
If you're a fisherman, you'll particularly enjoy this one. I have to admit to not
knowing about this method of "electrofishing" (although not called by that name
here) for drawing fish to a high voltage alternating electrical field and then capturing
them with a net once close enough to be paralyzed (stunned). A process called "galvanotaxis"
which causes uncontrolled muscular convulsion in the fish causes them to swim towards
the source...
""The adoption of 5G continues to thrive
in the mobile market, with a raft of device types beyond smartphones set to form
part of the wider ecosystem, extending to new industries and a wide array of device
categories, including automotive, Extended Reality (XR), Personal Computers (PCs),
wearables, mobile broadband and Industrial Internet of Things (IIoT). However, democratization
of this
extended 5G experience will be constrained, not just by the modem and application
processor, but also by the growing complexity of the Radio Frequency Front End (RFFE).
In turn, the sheer number of Radio Frequency (RF) components now needed in a 5G
device has grown exponentially, while pressure to improve performance and thermal
efficiency and condense the overall die size area have become ever more important
to help reduce cost and ensure integrity of the signal and communication reliability.
While the burden of 5G on the RFFE..."
There
are still plenty of us around who remember seeing
Radio Shack
commercials on TV back in the days when all television sets had at least one
vacuum tube in them - the CRT (cathode ray tube). As evidenced by the huge number
of vintage Radio Shack commercials posted on YouTube, and the amount of views for
them, there is still a desire by people to take a nostalgic trip back in time to
see the content they remember. Of course at the time we usually considered all commercials
an imposition on our TV program watching. One of the annoyances of modern TV programming
is that even though you have to pay for the service, you still have to sit through
even more commercial time per show than was imposed when reception was free (over
the air). I have to be honest and admit that I don't recall ever seeing any of the
Radio Shack commercials in this collection of videos, but they definitely have the
"look" of the ones I do remember from the days of yore. I used to visit...
Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his June 2022 newsletter that
features his short op-ed entitled "The Millimeter-Wave Debacle Revisited," where
he discusses some of the realities that have impacted the mm-wave portion of 5G
systems - the two biggest of which are cost and lagging technology (e.g., semiconductors)
to support the scheme. Nascent 6G plans which envision spectrum operation in realms
above 100 GHz are saddled with the same limitation (at least currently) as
5G. As always, Sam demonstrates a keen awareness of the industry for which his company,
Anatech Electronics, services...
When
metal-encased vacuum tubes came on the electronics scene in the 1930s, they
were billed as the innovation that was going to radically change the radio world.
The built-in Faraday shield properties of the tubes did in fact stop the effects
of cross-coupling between adjacent tubes and permit more densely packed circuits,
but they also caused some other problems as well. Capacitance between tube elements
and the shield caused electron flow control issues and affected operational frequency.
Packing tubes closer together also meant the rat's nest of resistors, capacitors,
inductors, and wires on the underside of the chassis that were installed in a point-to-point
manner rather than neatly on printed circuit boards (which largely did not exist
at the time) were closer together and therefore created new problems due to proximity.
Still, metal tubes served a very useful purpose when employed wisely and continued
in use along with unshielded tubes...
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...
Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets
exceedingly high standards of quality, performance and excellent value, and are
100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz.
Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production.
All products are custom designed. We will find a solution and save your time and
cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.
Wednesday the 17th
Robert Balin, Popular Electronics magazine's
quizmeister, created this
CapaciQuiz for the February 1961 issue. Most of these are elementary, but think
carefully about the exact wording of Q4 before you answer. With Q8, believe the
better explanation is that for a purely capacitive circuit, current and voltage
are 90° out of phase, so when the sinewave voltage is at zero, the current is at
a maximum. Note that Q6 and Q10 are opposites (parallel vs. series capacitor combinations),
so if you have trouble reasoning one of the configurations, work on the other and
then you'll know both. Bon chance!...
"Usually, when light travels through a material,
it produces an image. But when it passes through a new material developed by researchers
at the Australian National University (ANU), it produces two completely independent
and different images - as different, in fact, as the iconic outline of the Sydney
Opera House and the continent of Australia. This unusual effect is possible thanks
to nanoscale structures within the material that manipulate a light wave's direction
of travel in a way that could have applications for information processing and communications.
The nanoscale structures used in this research are ultrathin films comprising arrays
of tiny dielectric structures that behave much like atoms. Known as metasurfaces,
such structures are often employed in the design of miniaturized optical components,
and they can also be used to control the direction in which light can and cannot
travel at the nanoscale. For instance, some of these 'meta-atoms'
allow light to flow only from left to right, while others permit travel only from
the right to the left..."
"QRM" is the Q-code in Ham-speak for unwelcomed
manmade inband electrical interference. Interference is not just random signals
like noise from motor brush arcing, intermittent electric distribution system connections
or inter-conductor arcing, etc. An improperly tuned or ineffectively filtered radio
transmission, or EM energy leaking from a poorly shielded electronic device is also
QRM. I distinguish such noise as unwelcomed because what might be considered as
noise by one person could be a desired signal by another. "QRN" stands for electrical
noise generated in nature such as lightning bolts, solar storms, or even, as discovered
by Drs. Arno Penzias and Robert Wilson, the 160 GHz Cosmic Microwave Background
(CMB) radiation that emanates from all regions of the sky. A mnemonic for remembering
which Q-code is which is the trailing "M" for manmade and "N" for natural...
The
Wireless Telecom Group,
comprised of Boonton, CommAgility, Holzworth, and Noisecom, is a global designer
and manufacturer of advanced RF and microwave components, modules, systems, and
instruments. Serving the wireless, telecommunication, satellite, military, aerospace,
semiconductor and medical industries, Wireless Telecom Group products enable innovation
across a wide range of traditional and emerging wireless technologies. A unique
set of high-performance products including peak power meters, signal generators,
phase noise analyzers, signal processing modules, 5G and LTE PHY/stack software,
noise sources, and programmable noise generators.
Antenova Ltd, the UK-based manufacturer
of antennas and
RF antenna modules for M2M and the IoT, is adding a new offering to its range
of miniature Surface Mount Designed (SMD) antennas and modules for GNSS applications.
The new antenna, Agosti, part number SR4G080, measures 9.0 x 5.8 x 1.7 mm and
operates with exceptional efficiency in a reduced space on a corner of a PCB. The
key advantage of the Agosti antenna is its small ground plane requirement. Most
SMD antennas use the surface of the PCB around the antenna as a ground plane to
radiate signal from, so it is the ground plane requirement not the physical dimensions
of the antenna that defines the space it needs. Antenova's radiated measurement
results show Agosti operating well on small ground planes of 40 x 20 mm, 70
x 25 mm and 80 x 30 mm, making it a good choice for small form factor
designs...
The Yagi–Uda antenna (usually referred to
as a Yagi), is a relatively simple to construct multielement structure consisting
of a combination of driven (director) and reflective (reflector) diploes. Careful
phasing of the configuration results in a directional radiation pattern that is
used often for long distance (DX) and direction finding work. It is also useful
in a dense signal environment where there is a need to exclude received signals
not emanating from a preferred source. Common (or what used to be) rooftop television
antennas were of the Yagi type and served not just to pull in distant stations,
but to help reject multipath signals that would cause ghost images on the screen.
The concept is the 1926 brainchild of Messrs. Shintaro Uda and Hidetsugu Yagi, both
of the Tohoku Imperial University, in Japan. The Yagi antenna described in this
1952 issue of Radio & Television News magazine is for VHF channels
2-13...
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 12,000 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.
Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
RF and Microwave Test and Measurement
Equipment including attenuators & terminations; coaxial cables, connectors &
adapters; o-scopes; power meters & sensors; signal generators; antenna, signal,
spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth &
WLAN testers; PIM testers; amplifiers; power dividers; antennas.
Tuesday the 16th
The items reported in the September 1967
issue of Electronics World magazine represent the beginning stages of many
technologies that are still in used today. The monolithic ferrite memory was a major
producibility improvement in what was formally hand-wired toroidal matrices of cores.
They were the first step in integrated memory (although we don't use magnets anymore
in ICs (just on hard drives). The Electronically Controlled Robot looks like something
from a modern Japanese university - without the skin, hair, and eyeballs. Note that
as today, supplying power is one of the biggest hurdles in making a human-looking
robot (umbilical required). The Solid State Camera "Tube" is one of the very first
solid state camera imaging chips. It had a whopping 2,500 pixels. The Computer-Directed
Drawing Machine converted a 2-dimensional drawing into a 3-dimensional perspective.
Shipboard Satellite Communications was at the time one of the first uses of satellites
for global communications, it being a big deal because...
San Francisco Circuits (SFC) has launched
a new industry focus page on
PCBs used in wearable devices. This new industry focus page on PCBs for wearable
devices covers how these devices require small form factors and how they are achieved.
It also includes the material selection process, design & layout best practices,
wearable device applications, and the future of materials for wearable technologies.
As technology advances and more innovative applications are developed for wearable
devices, the circuit boards used in these applications will require a manufacturer
that understands the demanding requirements of flex PCBs. Select wearable device
applications include: virtual reality headsets, fitness trackers, glucose monitoring
systems...
Have you had a rough week? If so - and even
if not - take a few minutes to get a laugh from these
electronics-themed comics from the pages of vintage Radio News magazines.
Beginning sometime in the late 1930s and early 1940s, single-panel topical comics
began appearing frequently in many hobby and even professional magazines. Sure,
comics showed up in magazines before that time, but they generally did not necessarily
have to do with the main subject of the publication. The Saturday Evening Post,
for example, had many single-panel comics, but they were on any random theme. I
can't go without commenting on the April 1946 comic since it reminds me of a situation
while in tech school at Keesler AFB in Biloxi, Mississippi, in 1979. I can't recall
exactly what the circuit was that the instructor was covering, but it involved tuning
to achieve a waveform with a null in the center of two bandpass regions similar
to this: ∩∩ . He and everyone
I worked with in the field after tech school referred to it as the "Dolly Parton
waveform." Such a scenario would never pass muster with the overly sensitive...
Joe
Madden, of mobile Experts, has an interesting article in the August issue of
Microwave Journal where he discusses, per the title, "The Ideal Band
for 6G." As with every increment in wireless technology, the pursuit of higher
per-channel bandwidth drives the center frequencies farther into the nether regions
of mm-wave and beyond. Aside from no having existing technology (i.e., integrated
circuits) to support commercialization of the high bands, lack of obstacle penetration
and greater signal strength drop-off (per
Friis equation) buggers
the system. Mr. Madden has a useful 3-D graph illustrating the aforementioned
limiting characteristics of the various frequency bands. He begins the article by
noting that the original stated motivation for 5G enabling higher bandwidth local
application is not really being realized, but instead is exploited by carriers to
handle more traffic..
For many years, Popular Electronics
magazine had a monthly column titled "Transistor
Topics" that reported on news in the world of those newfangled semiconductors.
To wit, this article from the April 1960 edition begins, "Each month, more and more
transistorized consumer products are developed as replacements for vacuum-tube designs."
The Heathkit TCR-1 clock radio is featured for its six-transistor superheterodyne
AM receiver circuit. A mechanical clock is still used since other than using Nixie
tubes, digital displays were not commercially available. The MOBIDIC "super" computer
is also covered for its total transistorization. At about 4 feet wide and 6 feet
tall, it is hard to believe that the "MOB" portion of the acronym stands for "mobile"...
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 ...
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.
Monday the 15th
Yes, the old days of over-the-air broadcasts
and analog television could be a pain. Perfect adjustment of the
antenna and TV controls one day could be totally useless the next day or even
later the same day. Atmospheric and physical variations can change suddenly and
significantly, affecting both radio and television. Proper separation and processing
of horizontal and vertical synchronization of the video, color and intensity, and
audio by the TV's electronic circuits depended on the right combination of antenna,
and lead-in cable. The advent of semiconductors in place of vacuum tubes helped
stabilize the television's role in viewing quality and lessened the overall irritation
level, and the introduction of cable-based and then satellite-based programming
distribution to reduce irritations to the point where most people never had a problem.
That said, I would happily return to the days of yore and suffer the aforementioned
inconveniences, to enjoy a time when the content was significantly less rude and
crude, and patriotic and traditional family-based shows were by far the rule rather
than the exception...
The RF Cafe
Blog has a built-in poll feature that I can use to solicit statistical information
from visitors. This week's question is, "Do You Work from Home?"
Since the beginning of the COVID scam, a lot of people transitioned from driving
to a facility every day to working either full-time or part-time from home. How
about you?
"As the amount of data stored in devices
and shared over the internet continuously increases, computer scientists worldwide
are trying to devise new approaches to secure communications and protect sensitive
information. Some of the most well-established and valuable approaches are cryptographic
techniques, which essentially encrypt (i.e., transform) data and texts exchanged
between two or more parties, so that only senders and receivers can view it in its
original form.
Physical unclonable functions (PUFs), devices that exploit 'random imperfections'
unavoidably introduced during the manufacturing of devices to give physical entities
unique 'fingerprints' (i.e., trust anchors). In recent years, these devices have
proved to be particularly valuable for creating cryptographic keys, which are instantly
erased as soon as they are used..."
This could be a modern day photo of an American
DHS (Department of Homeland Security) or an Israeli IDF (Israel Defense Forces)
agent displaying a body bomb found on an attempted suicide bomber after thwarting
an attack, but it's not. In actuality, it is a 1934
Burgess
battery advertisement that appeared in QST magazine with the intent of demonstrating
to Hams the kinds of research the company was doing. This design was called a "ribbon
battery," and it could conveniently be wired in a flexible manner with almost any
number of series and parallel connections to accommodate required voltage and current
combinations, including taps for multiple voltages needed for vacuum tube radios.
The packs could be "wrapped about one's body for portable receiver use." Hmmmm,
maybe that's what made me think of the body bomb...
I stayed up late on the night of of December
11, 2012 (early in the morning, actually) to watch the
FITSAT-1 CubeSat satellite flash its Morse code "HI DE NIWAKA JAPAN" message
via super-bright LEDs over eastern North America. It was scheduled to pass just
south of my location in Erie, Pennsylvania, at 1:14 AM, with a lights-on intensity
great enough to be easily seen with binoculars. FITSAT-1 is a project conceived
of and built by professors and students at the Fukuoka Institute of Technology (FIT)
in Japan. In addition to the LED visual display, the satellite also carries several
Amateur Radio payloads including a CW beacon on 437.250 MHz, a telemetry beacon
on 437.445 MHz and a high-speed data downlink on 5,840.0 MHz. The CubeSat
Project was developed by California Polytechnic State University and Stanford University's
Space Systems Development Lab. It creates launch opportunities for universities
previously unable to access space. A CubeSat is 10 cm on a side and may have
a mass of up to 1.33 kg. Launch vehicles sell space to CubeSats for around
$40,000, which makes them very affordable to place in orbit...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils available for RF, analog, and digital system and schematic
drawings! Every stencil symbol has been built to fit proportionally on the included
A-, B-, and C-size drawing page templates (or use your own page if preferred). Components
are provided for system block diagrams, conceptual drawings, schematics, test equipment,
racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
Innovative Power Products (IPP) has over
35 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband
couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools available,
resulting in unrivaled product performance. Applications in military, medical, industrial
and commercial markets are serviced around the world. Products listed on website
link to detailed mechanical drawings that contain electrical specifications as well
as performance data. Please take a couple minutes to visit their website and see
how IPP can help you today.
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)
|