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Notices by hackaday (hackaday@apoil.org)

  1. hackaday (hackaday@apoil.org)'s status on Wednesday, 25-Apr-2018 16:01:05 EDT hackaday hackaday

    Forget your Nixies and Numitrons, Soviet-era pixel arrays are where it's at in vacuum displays! https://hackaday.com/2018/04/25/adventures-in-gas-filled-tube-arrays/ source: https://twitter.com/hackaday/status/989232843363639297

    In conversation Wednesday, 25-Apr-2018 16:01:05 EDT from apoil.org permalink

    Attachments

    1. Adventures In Gas Filled Tube Arrays
      By Brian Benchoff from Hackaday

      Vacuum tubes are awesome, and Nixies are even better. Numitrons are the new hotness, but there’s one type of tube out there that’s better than all the rest. It’s the ИГГ1-64/64M. This is a panel of tubes in a 64 by 64 grid, some with just green dots, some with green and orange, and even a red, green, blue 64 by 64 pixel matrix. They’re either phosphors or gas-filled tubes, but this is the king of all tube-based displays. Not even the RGB CRTs in a Jumbotron can match the absurdity of this tube array.

      [Muth] got his hands on a few of these panels, and finally he’s displaying images on them. It’s an amazing project that involved finding the documentation, translating it, driving the tubes with 360 Volts, and figuring out a way to drive 128 inputs from just a few microcontroller pins.

      First, the power supply. These panels require about 360 Volts to light up. This is significantly higher than what would usually be found in a Nixie clock or other normal tube-based display. That’s no problem, because a careful reading of the datasheet revealed a circuit that brings a normal-ish 180 Volt Nixie power supply up to the proper voltage. To drive these pixels, [Muth] settled on a rather large PIC18F microcontroller with eight tri-state buffers. The microcontroller takes data over a serial port and scans through the entire framebuffer. All in all, there are eight driver boards, 736 components, and 160 wires connecting everything together. It’s a lot of work, but now [Muth] has a 64×64 display that’s green and orange.

      You can check out a ‘pixel dust’ demo of this display in action below.

  2. hackaday (hackaday@apoil.org)'s status on Sunday, 22-Apr-2018 13:00:17 EDT hackaday hackaday

    Sometimes an upgrade works, sometimes it doesn't. What went wrong with this spot welder improvement? https://hackaday.com/2018/04/22/fail-of-the-week-the-spot-welder-upgrade-that-wasnt/ source: https://twitter.com/hackaday/status/988100183220244481

    In conversation Sunday, 22-Apr-2018 13:00:17 EDT from apoil.org permalink

    Attachments

    1. Fail of the Week: The Spot Welder Upgrade That Wasn’t
      By Dan Maloney from Hackaday

      Even when you build something really, really nice, there’s always room for improvement, right? As it turns out for this attempted upgrade to a DIY spot welder, not so much.

      You’ll no doubt recall [Mark Presling]’s remarkably polished and professional spot welder build that we featured some time ago. It’s a beauty, with a lot of thought and effort put into not only the fit and finish but the function as well. Still, [Mark] was not satisfied; he felt that the welder was a little underpowered, and the rewound microwave oven transformer was too noisy. Taking inspiration from an old industrial spot welder, he decided to rebuild the transformer by swapping the double loop of battery cable typically used as a secondary with a single loop of thick copper stock. Lacking the proper sized bar, though, he laminated multiple thin copper sheets together before forming the loop. On paper, the new secondary’s higher cross-sectional area should carry more current, but in practice, he saw no difference in the weld current or his results. It wasn’t all bad news, though — the welder is nearly silent now, and the replaced secondary windings were probably a safety issue anyway, since the cable insulation had started to melt.

      Given [Mark]’s obvious attention to detail, we have no doubt he’ll be tackling this again, and that he’ll eventually solve the problem. What suggestions would you make? Where did the upgrade go wrong? Was it the use of a laminated secondary rather than solid bar stock? Or perhaps this is the best this MOT can do? Sound off in the comments section.

  3. hackaday (hackaday@apoil.org)'s status on Friday, 20-Apr-2018 15:32:46 EDT hackaday hackaday

    Andrew Sowa @JunesPhD is sharing all their PCB art creation secrets in the #HackChat. Our chats our now in public channels, so you can join the conversation just with a link click like this one -> https://hackaday.io/messages/room/2369 https://twitter.com/hackaday/status/987413717242470400/photo/1 source: https://twitter.com/hackaday/status/987413717242470400

    In conversation Friday, 20-Apr-2018 15:32:46 EDT from apoil.org permalink

    Attachments

    1. Public chat for Hack Chat | Hackaday.io
      Participate in the public chat for Hack Chat!
  4. hackaday (hackaday@apoil.org)'s status on Thursday, 12-Apr-2018 13:01:34 EDT hackaday hackaday

    Clive Sinclair was a prolific electronics author in addition to his well-known hardware like the ZX Spectrum. Let's get to know his writing! https://hackaday.com/2018/04/12/clive-sinclair-the-other-author/ source: https://twitter.com/hackaday/status/984476625432711168

    In conversation Thursday, 12-Apr-2018 13:01:34 EDT from apoil.org permalink

    Attachments

    1. Clive Sinclair, The Other Author
      By Jenny List from Hackaday

      A reasonable selection of the Hackaday readership will have had their first experiences of computing on an 8-bit machine in a black case, with the word “Sinclair” on it. Even if you haven’t work with one of these machines you probably know that the man behind them was the sometimes colourful inventor Clive (now Sir Clive) Sinclair.

      The finest in 1950s graphic design, applied to electronics books.

      He was the founder of an electronics company that promised big results from its relatively inexpensive electronic products. Radio receivers that could fit in a matchbox, transistorised component stereo systems, miniature televisions, and affordable calculators had all received the Sinclair treatment from the early-1960s onwards. But it was towards the end of the 1970s that one of his companies produced its first microcomputer.

      At the end of the 1950s, when the teenage Sinclair was already a prolific producer of electronics and in the early stages of starting his own electronics business, he took the entirely understandable route for a cash-strapped engineer and entrepreneur and began writing for a living. He wrote for electronics and radio magazines, later becoming assistant editor of the trade magazine Instrument Practice, and wrote electronic project books for Bernard’s Radio Manuals, and Bernard Babani Publishing. It is this period of his career that has caught our eye today, not simply for the famous association of the Sinclair name, but for the fascinating window his work gives us into the state of electronics at the time.

      Step back to a time when AM was king …

      How to identify a tip-body-dot resistor or a moulded mica capacitor.

      With a little persistence we were able to locate some of the early [Sinclair] work: 1959’s Practical Transistor Receivers Book 1, and 1962’s Modern Transistor Circuits For Beginners. They are both slimline paperback volumes roughly the size of an A4 or US Letter sheet, and contain 36 and 35 different circuits respectively.

      Practical Transistor Receivers was one of the first such books on transistor circuitry from this publisher, and was evidently intended to serve as a transistor primer for constructors who had never used the new devices. There is an extensive section on both the range of transistors and of diodes that were on the market in 1958 when it was written. This is an interesting read in itself, containing as it does a look at many long-disappeared names in the industry on both sides of the Atlantic. All the semiconductors are germanium, diodes are point-contact, all but a few transistors are PNP, and though there are no point-contact transistors by this stage in the decade all but a few surface barrier devices use alloy-diffusion construction. Gain and cut-off frequency figures are extremely low by today’s standards, these devices are still very much the earliest examples of their type.

      Modern Transistor Circuits For Beginners is pitched more towards people unfamiliar with electronics, and contains a chapter introducing the components of the day. There are the discrete components that will be familiar to readers in 2017, but also a table of colour codes with examples of devices you might not have encountered that use them. You know about resistors with coloured bands, but have you ever seen a tip-body-and-dot resistor?

      Probably the simplest possible transistor radio circuits.

      It is especially interesting that both books deal with exactly the same subject of simple AM radio receivers, despite the title of Modern Transistor Circuits leading the reader to believe otherwise. Electronics was entirely synonymous with radio and audio at the amateur level at the time, and this book follows a trend that is evident from the list of other titles from the same publisher on the back cover.

      The circuits start with the very simplest receivers which are not much more than a crystal set with an audio stage added, and move through tuned-radio-frequency designs to regenerative and super-regenerative receivers. Modern Transistor Circuits has a few layout diagrams for good measure, to aid the beginner in identifying transistor leads.

      Another feature of these circuits is that they show an obvious heritage from the tube-based circuits that anyone involved in electronics would have been familiar with at the time. Transformers are used as inter-stage coupling where we would now use a capacitor or a level shifting circuit, and power amplifiers are high-impedance single-ended designs. The super-regenerative circuit has a quench oscillator using a sizeable LC tuned circuit, where an RC oscillator of some type would almost certainly be placed in a modern take on the same design.

      … and transistors cost an arm and a leg.

      This simple three-transistor radio wouldn’t cost much with today’s equivalents, but back in 1960 it could have been a major outlay.

      Nearly sixty years ago a transistor was an exotic and expensive device. Equivalents for an OC71 audio transistor appear in an advert in the back of Modern Transistor Circuits for 5 shillings and 9 pence, which with a bit of conversion to decimal currency and taking into account the inflation of the intervening years, equates to £6.03, or $8.45 in 2018 terms. Today I can buy a tape of 40 2N3904 silicon transistors with a gain figure in the several hundreds and a cut-off frequency in the high VHF range for that price from a retail supplier, and of course for similar prices I can also benefit from five decades of integrated circuit development. It’s possible then that radio circuits were the main outlet for electronics enthusiasts at the time because they were something that could deliver a reasonable result from a circuit with relatively few components, anything requiring multiple devices would have soon bankrupted anyone wanting to try them.

      A Sinclair miniature radio in the Science Museum, London. Frankie Roberto [CC BY 2.0].The [Sinclair] business developed through the decade with radio kits that brought to the fore his love of miniaturisation that would become the signature of products bearing the name. You can see the further development of some of the radios in these books with his rise to public prominence through his long progression of tiny radios designed to fit in a matchbox, a theme to which he returned in the 1990s with an FM radio in an earpiece. In the 1970s came the calculators and the miniature televisions, followed into the 1980s through a separate Sinclair company by the home computers that would eventually be sold to Amstrad. He is infamous for his mid-1980s C5 three-wheeled electric buggy, but he pursued his interest in alternative transport into the 1990s with a succession of folding bicycles of unusual design, and an electric drive add-on for conventional bicycles.

      Footnote: though Sir Clive Sinclair is a published author and famous name in the world of home computers, it is fair to say that he is not the Clive Sinclair, author. That honour must go to Clive Sinclair, the prolific British novelist, who sadly died at the start of March 2018.

  5. hackaday (hackaday@apoil.org)'s status on Tuesday, 03-Apr-2018 13:01:45 EDT hackaday hackaday

    Meet the woman who fought long and hard to put a telescope in space. https://hackaday.com/2018/04/03/nancy-grace-roman-mother-of-the-hubble/ source: https://twitter.com/hackaday/status/981215182885216259

    In conversation Tuesday, 03-Apr-2018 13:01:45 EDT from apoil.org permalink

    Attachments

    1. Nancy Grace Roman, Mother of the Hubble
      By Kristina Panos from Hackaday

      When she was four years old, Nancy Grace Roman loved drawing pictures of the Moon. By the time she was forty, she was in charge of convincing the U.S. government to fund a space telescope that would give us the clearest, sharpest pictures of the Moon that anyone had ever seen. Her interest in astronomy was always academic, and she herself never owned a telescope. But without Nancy, there would be no Hubble.

      Goodnight, Moon

      A view of the Milky Way from Reno, Nevada. Via Lonely Speck

      Nancy was born May 16, 1925 in Nashville, Tennessee. Her father was a geophysicist, and the family moved around often. Nancy’s parents influenced her scientific curiosities, but they also satisfied them. Her father handled the hard science questions, and Nancy’s mother, who was quite interested in the natural world, would point out birds, plants, and constellations to her.

      For two years, the family lived on the outskirts of Reno, Nevada. The wide expanse of desert and low levels of light pollution made stargazing easy, and Nancy was hooked. She formed an astronomy club with some neighborhood girls, and they met once a week in the Romans’ backyard to study constellations. Nancy would later reminisce that her experience in Reno was the single greatest influence on her future career.

      By the time Nancy was ready for high school, she was dead-set on becoming an astronomer despite a near-complete lack of support from her teachers. When she asked her guidance counselor for permission to take a second semester of Algebra instead of a fifth semester of Latin, the counselor was appalled. She looked down her nose at Nancy and sneered, “What lady would take mathematics instead of Latin?”

      Reaching for the Stars

      For college, Nancy chose Swarthmore. They had a strong astronomy program founded by Susan Cunningham, who’d studied under Maria Mitchell at Vassar. Unfortunately, World War II was in full swing, and many of the teachers had left to help with the war effort.

      The Cunningham Observatory. Via Swarthmore

      The school’s observatory was in a sad, neglected state and was being used as a silo for onion storage by some locals. Determined to study the cosmos, Nancy and another student took the telescopes apart, cleaned and reassembled them, and made adjustments so they would work better.

       

      Nancy graduated with a BA of Astronomy in 1946 and went to the University of Chicago for her PhD. After graduating, she stayed on to work at the university’s Yerkes Observatory in Wisconsin. One day, as she was trying to determine the relationship between the composition of a star and its location within a galaxy, she observed a star with unusual emission spectra. It seemed a bit strange, but she didn’t think much of it. She wrote a two-page note about it and went back to work. The star she observed, a binary system later named AG Draconis, would turn out to be her lucky star. It only exhibits such bursts of activity for about 100 days every 10 or 15 years.

      While Nancy greatly enjoyed teaching and research, she figured that a woman would never get tenure at a research institution. She changed her specialization to stay close to research and took a position in the radio astronomy program of the U.S. Naval Research Laboratory (NRL) in Washington.

      A few years into this post, she received an unexpected invitation to attend the dedication of a new observatory in Armenia. The new observatory’s director had read her two-page note about that unusual star she’d seen at Yerkes and was intrigued by her discovery, so he invited her to take the place of someone who’d had to drop out.

      Nancy only had about four weeks to get permission from the Navy and secure entry into the Soviet Union during the Cold War, but she managed. The news of her invitation traveled quickly around the NRL, and they asked her to speak about her trip and lecture her colleagues when she returned.

      NASA Brass

      Nancy with a model of an Orbiting Solar Observatory. Via NASA

      Nancy enjoyed lecturing about astronomy to an audience already versed in engineering and physics because she could explore the topics more deeply. She gained a lot of recognition and notoriety from giving these lectures, and when NASA was formed in 1958, the powers that be came to her to recommend someone who could start a space astronomy program. Nancy took this as a suggestion that she submit her own name. It was difficult to leave research, but she couldn’t resist the opportunity to influence the future of astronomy for decades to come.

       

      Nancy was the first female executive employed by NASA. She was responsible for developing several space astronomy programs, budgeting them, and seeing them through to completion. She oversaw the development of astronomical satellites and was involved in launching three Orbiting Solar Observatories that used gamma and x-rays to study the Sun from low-Earth orbit.

      One of her duties was taking the temperature of the astronomy community. She traveled all over the U.S. with NASA engineers in tow to find out what astronomers wanted most from the newly formed organization. The engineers were there to verify the feasibility of their wishes. Most of them said they wanted a telescope in space, but they didn’t all agree. Many respected astronomers were anti-space, and believed that everything could be done better from the ground as long as they kept building bigger and better telescopes. Before Nancy convinced Congress, she had to convince the astronomy community.

      Mother of the Hubble

      Nancy has often compared Earth’s atmosphere to an old stained glass window. We can see through it, but dust particles and irregularities in the glass distort the view and obscure a lot of detail. Earth’s atmosphere acts the same way; it blocks some light completely, and distorts the light that does get through.

      Hubble’s image of the Eagle Nebula giving birth to stars. Via NASA.

      Much of the light that gets blocked is crucial to furthering our understanding of the universe because it allows us to measure the speeds of stars and galaxies. Putting a telescope above the atmosphere seemed to be the leap that science needed.

      The idea of putting a telescope in space was not a new one. A Princeton professor, Lyman Spitzer, had first proposed the idea in 1946, but there were too many technological challenges to overcome first.

      As Nancy found out, there were human challenges as well. It would cost a great deal of money and require a lot of time and research to even design a space telescope. But the money came first. Nancy and NASA had to convince Congress that launching a telescope into space was worth every penny because of the promise of advancing our understanding of the universe.

      She and her superiors held many dog-and-pony-show dinners for men with political power who lacked scientific backgrounds. For ten years, she wrote congressional testimony that was then given to Congress by her male counterparts. Funding the Hubble was a hard road, and NASA was rejected many times. Even after Congress approved, there were plenty of vocal naysayers.

      Mother, Should I Trust the Government?

      Nancy retired from NASA in 1979 and tried to leave the project in capable hands, but it suffered major financial, engineering, and management problems that went beyond any single person’s control. The proposed Hubble launch was set for 1983, then 1986, but was further delayed by the Challenger disaster. It was finally put into orbit on April 24, 1990.

      Nancy credits her successes to a mixture of luck, determination, and her ability to speak and write well. She was never discouraged by the educators who insisted that she had no place in astronomy or physics. She simply knew it was what she wanted to do, and she believed in herself.

      What mattered most to Nancy was advancing space exploration. She has had a very active retirement, traveling all over to teach and lecture. She is an outspoken advocate for women in the sciences, and takes every opportunity to encourage girls who are interested in astronomy.

  6. hackaday (hackaday@apoil.org)'s status on Monday, 02-Apr-2018 11:30:11 EDT hackaday hackaday

    What is the sound of one robot preparing tea? https://hackaday.com/2018/04/02/zen-and-the-art-of-japanese-tea-robots/ source: https://twitter.com/hackaday/status/980829748980051970

    In conversation Monday, 02-Apr-2018 11:30:11 EDT from apoil.org permalink

    Attachments

    1. Zen and the Art of Japanese Tea Robots
      By Christopher Wang from Hackaday

      In Japan, tea ceremony (cha-dou) is revered as a way to a gain deeper insights into life and philosophy. Traditional Japanese tea ceremony practitioners put in long hours to master the intricacies and details of pouring tea. The road to becoming a tea master is crucial as it develops the practitioner’s mental state as well as physical technique.

      However if you don’t have time to master the “way of tea”, then you can build a bot and automate your zen experience. That’s exactly what the people at Ano Labs did when they built their Japanese Tea Ceremony Robot #151A.

      The Japanese hacking scene is really interesting because there’s an aesthetic to creating very technical things that perform tasks that aren’t particularly useful. Another example would be this Lego Bubble Wrap Popper:

  7. hackaday (hackaday@apoil.org)'s status on Friday, 13-Oct-2017 11:30:49 EDT hackaday hackaday

    Follow build of ultimate hardware controller for Oberheim Matrix 1000 synth: https://hackaday.io/project/10768-matrix-midi-controller #hackadayio https://twitter.com/hackaday/status/918861580284125184/photo/1 source: https://twitter.com/hackaday/status/918861580284125184

    In conversation Friday, 13-Oct-2017 11:30:49 EDT from apoil.org permalink

    Attachments

    1. Matrix Midi Controller
      The Matrix-1000 synth is a powerful analogue polyphonic synthesizer trapped in a 1HU rack module. It doesn't offer any means to edit the myriad of parameters that define a sound (or "patch" in synth talk). In 2000, I wrote and published a succesful software solution for this problem (Matrix 2001 for Windows XP). I've been eyeing the Arduino for a while and recently decided to take the plunge and buy some kit so I would be able to determine if building a dedicated hardware controller is feasible for an electronics newbie like me.
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