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  1. #91
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    Three dimensional cams. I love the Mk1/Mk1a.

    https://en.wikipedia.org/wiki/Rangek...ical_functions for more fun computer history.


  2. #92
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    31st December 2009
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    Quote Originally Posted by Handeman View Post
    I learned a little about those types of computers and how they work while in the Navy in '81. The Fire Control computer for the 16" guns on the Battleships were still analog computers with the synchros, servos, electrical adders, etc. Those solved the fire control problem for the main guns and were in use well before WWII. I don't know if they solved differential equations, but they took a lot of inputs from dials and switches and instantly aimed the guns.
    Even the simplest PID servo controller solves a 2nd-order differential equation. The fire control systems started out fairly basic but evolved to include many more inputs, including ship-motion gyros, windage, etc. I was lucky to take two courses from Richard Miller in the late 70's. He worked for General Electric in Schenectady NY before and during WWII designing controllers for gun turrets. We had lab benches just as crazy looking as the one Winston posted (slightly more "modern"), plus large motors bolted to the floor. Still have the book he wrote and have used it over the years.

    -John

    NAR/TRA L3
    My LinkedIn Profile

  3. #93
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    Quote Originally Posted by Handeman View Post
    I learned a little about those types of computers and how they work while in the Navy in '81. The Fire Control computer for the 16" guns on the Battleships were still analog computers with the synchros, servos, electrical adders, etc. Those solved the fire control problem for the main guns and were in use well before WWII. I don't know if they solved differential equations, but they took a lot of inputs from dials and switches and instantly aimed the guns.
    While in the general area of the country to see a shuttle launch, I visited the USS Alabama museum and one of the tour locations was the fire control room. Your post led me to search for more info on 16" fire control and I found this very interesting article:

    Gears of war: When mechanical analog computers ruled the waves
    In some ways, the Navy's latest computers fall short of the power of 1930s tech
    Mar 2014

    https://arstechnica.com/information-...led-the-waves/
    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  4. #94
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    Quote Originally Posted by dhbarr View Post
    Three dimensional cams. I love the Mk1/Mk1a.

    https://en.wikipedia.org/wiki/Rangek...ical_functions for more fun computer history.
    Cool. Thanks for that link.
    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  5. #95
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    Beautiful:



    EUV Lithography Finally Ready for Chip Manufacturing
    This long-awaited technology will extend the life of Moore’s Law
    5 Jan 2018

    https://spectrum.ieee.org/semiconduc...-manufacturing

    Excerpt:

    EUV lithography’s reason for being is that it uses 13.5-nm light, which is much closer to the size of the final features to be printed. With it, manufacturers can turn three or four lithography steps into one. For its 7-nm EUV process, GlobalFoundries will replace 15 steps with just 5. John Lin, TSMC’s director of litho equipment and mask technology, says his company plans a similar reduction.

    While that will make the work at 7 nm faster and cheaper, it’s the nodes beyond where EUV will be absolutely crucial. “If you didn’t use EUV for 5 nm, it’d be more than 100 [lithographic steps],” says Patton. “That’d be insane.”

    Patton makes it sound as though EUV lithography arrived just in time, and in a way it has. But it has been a decades-long journey with many moments when one expert or another declared it dead. Its arrival in production now still seems a bit unbelievable to some observers.

    Throughout most of EUV’s history, the main problem has been the light source, and considering its complexity, that’s not surprising. In a vacuum chamber at one end of the machine, microscopic droplets of molten tin are fired in a stream as two laser blasts strike each of them sequentially. The first one hits the droplets so precisely that they flatten into misty discs. The second blasts them with so much power that they become little balls of plasma shining with EUV light.


    Light-source developers couldn’t provide the needed power for years, and they consistently overpromised and underdelivered. But now concerns about the light source have basically been put to rest. One source capable of outputting 205 watts of light is ready to ship, and ASML has demonstrated 250 W in the lab. “We are confident that ASML will achieve 250 W in the field in 2018,” says TSMC’s Lin.

    Even though most of the light is lost on its multireflector trip through the machine, that wattage will work even for the 5 nm node. But for 3 nm, analysts think that chipmakers will need 500 W, and maybe 1,000 W a couple generations further on for 1 nm. The former is doable through a combination of increasing the power of the drive lasers, improved efficiency at converting the laser energy to EUV light, and more precise stability and control. But the latter would require an absurd amount of power. The EUV tool and its associated drive lasers and other equipment I saw at GlobalFoundries draw about 1 megawatt to ultimately deliver just a few tens of watts of light power to the wafer. Caulfield tells me they had to add 10 percent to Fab 8’s power supply to accommodate the two EUV tools being installed for 2018.
    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  6. #96
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    31st January 2009
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    A problem with REALLY thin wires:

    Cobalt Could Untangle Chips’ Wiring Problems
    Intel and GlobalFoundries are replacing some copper connections with the resilient, conductive metal

    https://spectrum.ieee.org/semiconduc...iring-problems

    Today’s computer chips contain tens of kilometers of copper wiring, built up in 15 or so layers.

    As the semiconductor industry has shrunk the size of transistors, it has also had to make these interconnects thinner. Today, some wiring layers are so fine that [TINY] electrical currents can actually damage them. And chipmakers are running out of new ways to deal with this problem.

    Copper boasts lower resistivity than aluminum, tungsten, and even cobalt. However, copper is particularly vulnerable to another problem at small scales called electromigration. As electrons speed through ultrathin wires, they dislodge atoms in the metal, bumping them out of the way like a harried commuter jostling a tourist off the sidewalk.

    To protect copper interconnects, the thin wires are lined with other materials, such as tantalum nitride or even cobalt. “Copper moves easily, and you need a 1- to 2-nm barrier to contain it,” says Kevin Moraes, a product manager at Applied Materials, a supplier of semiconductor equipment.

    As copper interconnects get smaller, the tantalum nitride liner remains relatively thick—it’s difficult to make the liner much thinner than a nanometer or so, and it reaches a point where there’s more liner than wire. “The liner steals area from the copper and raises line resistance,” says Edelstein.

    At IEDM, Intel reported that moving to cobalt interconnects for the *finest-featured two layers of its 10-nm process technology, where interconnects are smallest, reduces electromigration by a factor of 5 to 10 and lowers resistance by a factor of 2. These improved interconnects should help the semiconductor industry shrink transistors ever further—without tripping over a wiring problem.
    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  7. #97
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    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  8. #98
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    21st May 2016
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    Got a coupon for a free SD card from microcenter, so I picked up a pi zero W. I'm thinking I'll set it up for on-board camera and maybe baro sensor for flight recording (not for recovery, as it has no clock and I don't think I'd rely on one for dd) Might have to cut a "Tux" sticker on my wife's cameo to add to the payload bay, or maybe a "Powered by Linux" sticker or something.
    ~Tom~

    NAR# 101538
    L1 - 12/17/17 Madcow Super Batray H170 @ MDRA

  9. #99
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    31st January 2009
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    From the comments:

    "Wow, I'm impressed you've been able to keep track of all those wires! How many times have you accidentally pulled out a wire you didn't mean to?"

    "1 time only actually! And it generated a bug that took me 2 days to find ?"

    "Replacing all the jumpers by short, straight wiring is one of the plans in the future Daniel It will improve my signals a lot. But for now they're ok!?"


    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  10. #100
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    10th July 2007
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    I went to an engineering exhibition back in 1977 and saw the first Pong game that come to Australia. Amazing. Had to queue up for about 15 minutes to get a turn at it.

    I also remember trying a Russian laser rifle at the same show. Built and weighed like an AK-47, but had a laser for target practise.
    TRA 13430, Level 3

    "Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

  11. #101
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    Robonaut Has Been Broken for Years, and Now NASA Is Bringing It Home
    A mysterious hardware problem has kept the ISS Robonaut out of action since at least 2015, so it's returning to Earth for a fix

    https://spectrum.ieee.org/automaton/...inging-it-home





    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  12. #102
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    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  13. #103
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    Why AMD is going to absolutely CREAM Intel in price/performance even more than now until Intel does this, too.



    The advancements in general. Amazing:

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  14. #104
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    The widely used, 2 million dollar, 5,000 pound, 100 megabyte hard drive whose gyroscopic precession actually tipped a prototype military mobile computing center truck onto its side. How far we've come...:

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  15. #105
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    31st January 2009
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    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  16. #106
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    31st January 2009
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    First Lithographically Produced Home Made IC

    He made a dual differential amplifier IC.

    https://hackaday.com/2018/04/24/firs...-ic-announced/

    http://sam.zeloof.xyz/category/semiconductor/

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  17. #107
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    To achieve 7nm, a description from various articles. The completed system will go into limited operation this year at GlobalFoundries:

    This partially assembled Extreme Ultraviolet (EUV) scanner at ASML’s headquarters in Veldhoven, Netherlands, is one of the company’s more recent models. (Oct 2016)



    Nothing about it was easy. Physics offers few favors for engineers hoping to cast patterns with what are essentially X-rays. At 13.5 nm, the wavelength the company ultimately chose, light is readily absorbed by many materials. Even the air we breathe “is absolutely black,” absorbing every last bit of the radiation, van Dijsseldonk notes. So he and his colleagues realized early on that the only way an EUV scanner could work was in vacuum, with each wafer entering and leaving the scanner through an air lock.

    And then there’s the problem of bending the radiation. EUV is also absorbed by glass, so directing it through the machine would require a shift from lenses to mirrors. And not just any mirrors. A simple polished surface would not be nearly reflective enough, so they’d have to use Bragg reflectors—multilayer mirrors that can constructively reinforce many small reflections into a single, reasonably strong one.

    Today, the mirrors inside ASML’s EUV machines consist of 40 pairs of alternating silicon and molybdenum layers—each just a few nanometers thick. Zeiss, the company that developed these mirrors, constructs their aspheric surfaces with great precision. But at the end of the day, van Dijsseldonk says, “if you do it fantastically [well], you get a mirror with a reflectivity of 70 percent.” That level of reflectivity means that, for every pair of mirrors used in the system, the light is cut by half. And a scanner could easily require a dozen mirrors to take light from the source to the mask—itself a mirror—and then on to the wafer. After an EUV beam has traversed this gauntlet, less than 2 percent of the light may be left.

    The less light that reaches a wafer, the longer a wafer must remain in the scanner to be exposed. And in a fab, time means money. For EUV to make it into commercial use, it needs to be able to compete with the cost of existing lithographic methods. So the losses among the mirrors have to be compensated by a radiation source that is extremely bright. And that proved to be really, really hard to engineer.

    To create EUV light, Cymer uses an approach called laser-produced plasma, which fires 50,000 microscopic droplets a second of ultrapure molten tin across a vacuum chamber, hitting each with powerful CO2-laser light generated by a series of amplifiers derived from a design originally used for metal cutting. When a laser pulse hits a molten tin droplet, it heats it up into an EUV-emitting plasma. A collector mirror reflects light created in this process and casts it into the scanner. Because the approach generates EUV light as well as tin debris, hydrogen gas constantly flows across the collector mirror to keep it from being rapidly covered with a layer of tin.

    To create EUV light, molten tin droplets are flattened by one laser pulse and then converted to light-emitting plasma by a second pulse:




    “The first time I heard about it, I thought it was insane,” admits ASML’s Alberto Pirati, who joined the company’s EUV light-source program in early 2013. But little by little, the team achieved the seemingly impossible. One of the biggest breakthroughs came with the introduction of a technique the Cymer team began exploring before being acquired by ASML. They found that if they fired a “prepulse” before the main laser, they could flatten each tin droplet into a pancake, creating more surface area for the main laser to hit and increasing how much of the tin droplet was converted to plasma. The change has boosted the laser-to-EUV conversion efficiency from a meager 1 percent to some 5 percent. Earlier this year, thanks to the prepulse and other optimizations, ASML reported that it had reached 200 W in the lab. Another light-source developer, Gigaphoton, has also reported great progress. The long-awaited production target of 250 W no longer seems far off. But the true test of whether EUV is ready to go into production will happen in the labs and fabs—and spreadsheets—of ASML’s chipmaking customers.

    The list price of ASML’s newest EUV machine exceeds €100 million, more than twice that of an average 193-nm scanner, says spokesperson Niclas Mika. It is about the height and width of a New York City bus and is shipped in multiple 747s. Customer estimates suggest such a machine, run at mass-production levels, could consume some 1.5 megawatts or so of electricity.




    The fab space is astonishing to see in person. You know academically how complex these things are, but seeing them is something different:



    A primary remaining obstacle to rapid wafer production using EUV:

    Next EUV Challenge: Pellicles
    Protecting photomasks at high temperatures is proving difficult and expensive.

    https://semiengineering.com/next-euv...nge-pellicles/

    Basically, a pellicle is a thin, transparent membrane that covers a photomask during the production flow. The pellicle is a dust cover, as it prevents particles and contaminates from falling on the mask. It also must be transparent enough to allow light to transmit from the lithography scanner to the mask.

    EUV pellicles are required to put EUV lithography into mass production, at least for logic chips. If a particle lands on an EUV mask, the scanner would likely print an unwanted defect on a wafer.

    And just one defect is a disaster, especially for logic. “If we have one defect, that means the whole die is gone,” said Banqiu Wu, principal member of the technical staff and chief technology officer for the Mask and TSV Etch Division at Applied Materials.

    ASML’s polysilicon-based EUV pellicle, which is just 50nm thick, must withstand an enormous amount of heat. When EUV light hits the pellicle, the temperature of the membrane will heat up anywhere from 600 to 1,000 degrees Celsius. The melting point of silicon is 1,414 degrees Celsius.

    In theory, the pellicle will dissipate the heat. But at those temperatures, there are also fears that the EUV pellicle could deteriorate during processing, causing damage to the EUV mask and scanner.

    Pellicles are an important part of the IC-manufacturing supply chain. Today’s optical photomasks consist of an opaque layer of chrome on a glass substrate. In the production flow, a scanner tends to generate unwanted particles and contaminates. So for decades, the industry has used a pellicle on the mask. The pellicle for an optical mask is based on a thin polymer material.

    EUV masks are different than traditional photomasks. An EUV mask blank consists of 40 to 50 alternating layers of silicon and molybdenum. The multi-layer stack serves as a mirror or reflector for EUV light.

    Once the EUV mask is fabricated, it is placed in an EUV lithography scanner. The tool projects light through the mask, which, in turn, patterns the images on a wafer.


    However:

    Extreme UV chip defects may force a new approach to processor design
    27 Feb 2018

    https://arstechnica.com/gadgets/2018...p-fabricating/

    Chips built with extreme ultraviolet (EUV) light are plagued with random defects with no obvious solution, according to research presented at a chipmakers' conference reported in EETimes. The EUV hardware seems to work acceptably for 7nm or larger processes, but below this scale, small defects are cropping up that ruin the chip and prove hard to detect.

    If these problems can't be ironed out, they may force a different approach to chip design. Chips that combine memory with processing elements and chips based on neural networks are more resilient to manufacturing defects, as the individual bad elements can be disabled while still salvaging the chip as a whole. IBM's True North neuron-simulating processor has a grid of 4096 elements, each combining some memory with some compute power, and last week researchers published that they had built "memtransistors." These combine transistors with memristors (devices that change their resistance depending on their "memory" of how much electric charge has passed through them). These hybrids integrate computation and memory at a very low level.
    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  18. #108
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    31st January 2009
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    Home made IC info continued:

    http://sam.zeloof.xyz/first-ic/

    Excerpts:

    Design

    I designed the Z1 amplifier looking for a simple chip to test and tweak my process. Layout was done in Magic VLSI for a 4 mask PMOS process (active/doped area, gate oxide, contact window, and top metal.) PMOS has advantages over NMOS as far as mobile ionic contamination that lends it to being fabricated in a garage. The masks are designed in 16:9 aspect ratio for easy projection.

    The feature (gate) size is approximately 175µm although there are test features as small as 2µm on the chip. Each amplifier section (center and right) contain 3 transistors (2 for long-tailed differential pair and one as current source/load resistor) which means a total of 6 FETs on the IC. The left portion of the IC contains resistors, capacitors, diodes, and other test features used to characterize the fabrication process. Each node of the differential pairs is broken out to a separate pin on the lead frame so it can be analyzed and external biasing can be added as necessary.

    Fabrication

    There are 66 individual fabrication steps to make this chip and it takes approximately 12 hours for a full run. The process yield can be as high as 80% for these large features, but is largely dependent on my coffee intake that day. I have also made Youtube videos covering semiconductor fabrication theory and discrete MOSFET fabrication.

    50mm Si wafers are scored into 5.08 x 3.175mm dies (~16mm^2 area) with a Epilog fiber laser. This die size is chosen to fit into a Kyocera 24pin DIP carrier.

    Lithography process details

    The active area mask is exposed with my Mark IV maskless photolithography stepper at 365nm UV and the pattern is developed in KOH solution.






    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  19. #109
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    31st January 2009
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    VCF EAST: THE DESKTOP ENIAC
    24 May 2018

    https://hackaday.com/2018/05/24/vcf-...desktop-eniac/

    ENIAC: THE WAY WE WERE

    https://hackaday.com/2017/01/31/eniac-the-way-we-were/

    ENIAC: Then and Now

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  20. #110
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    17th May 2018
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    Boston, M.A
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    The price is quite lofty but the design is amazing! Interesting electronic indeed. Could inspire some of the technical minds.

  21. #111
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    Inside Intel's first product: the 3101 RAM chip held just 64 bits

    http://www.righto.com/2017/07/inside...-3101-ram.html

    Layers were hand drawn, checked with magnifying glasses, manually checked for design rules and layout vs. schematic checks. The final layout was cut out of Rubylith, and painstakingly checked for peeling and cutting errors. Actually, Intel's first RAM chip held only 63 bits. There was a mistake peeling the Rubylith mask so one address was inoperative. See "Recollections of Early Chip Development at Intel", Andrew M. Volk, Peter A. Stoll, and Paul Metrovich. 90% of chip errors when ICs were laid out in this way were due to those manual peeling errors.

    Rubylith layout of an IC:



    The 3101 RAM chip:



    Carver A. Mead, Ph.D., Moore Professor of Engineering & Applied Science, Emeritus, Caltech, presents, “The History of VLSI,” at the University of Washington on February 1, 2011. He describes how the layout and design process was automated even before it was absolutely essential to do so due to increasing chip complexity. He just thought the manual process was way too much of a PITA.

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  22. #112
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    VERY impressive. Beautiful execution of an extremely complex process.

    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

  23. #113
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    Re-creating the First Flip-Flop
    The fundamental building block of modern digital design turns 100
    25 May 2018

    https://spectrum.ieee.org/geek-life/...first-flipflop

    Many engineers are familiar with the names of Lee de Forest, who invented the amplifying vacuum tube, or John Bardeen, Walter Brattain, and William Shockley, who invented the transistor. Yet few know the names of William Eccles and F.W. Jordan, who applied for a patent for the flip-flop 100 years ago, in June 1918. The flip-flop is a crucial building block of digital circuits: It acts as an electronic toggle switch that can be set to stay on or off even after an initial electrical control signal has ceased. This allows circuits to remember and synchronize their states, and thus allows them to perform sequential logic.

    The flip-flop was created in the predigital age as a trigger relay for radio designs. Its existence was popularized by an article in the December 1919 issue of The Radio Review [PDF], and two decades later, the flip-flop would find its way into the Colossus computer [PDF], used in England to break German wartime ciphers, and into the ENIAC in the United States.

    Modern flip-flops are built in countless numbers out of transistors in integrated circuits, but, as the centenary of the flip-flop approached, I decided to replicate Eccles and Jordan’s original circuit as closely as possible.


    A 100TH BIRTHDAY CELEBRATION FOR THE FLIP FLOP

    https://hackaday.com/2018/06/04/a-10...the-flip-flop/


    "I don't make jokes. I just watch the government and report the facts." - Will Rogers

    "If you don't read the newspaper, you're uninformed. If you read the newspaper, you're misinformed." - Mark Twain

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