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Open Source Russian Vacuum Fluorescent Tube Clock

Posted by kdawson on from the ice-blue dept.

ptorrone writes "Hacker extraordinaire Ladyada (whose open source hardware projects we have discussed before) has just published a complete how-to, with design document, on making your own open source Russian vacuum fluorescent clock. The vacuum fluorescent tubes aren't as dangerous as (high-voltage) Nixie tubes, and there seem to be more of them available in the world. If you're not interested in building a clock from scratch, you can also pick up a kit version. All the schematics, source code, and files are available on the project's page."

155 comments

  1. It has software? by Anonymous Coward · · Score: 2, Informative

    I've built Nixie clocks, and there shouldn't be any software involved at all. You can get clock ICs cheaply enough, a microprocessor is overkill for this kind of project.

    1. Re:It has software? by Locutus · · Score: 2, Insightful

      but it's hackable and they even saved a few bucks by using the microcontroller to create the HV to run the tube.
      The microcontroller is an atmega168, just like what's in the Arduino but I didn't see if it was straight C or Arduino code.

      LoB

      --
      "Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
    2. Re:It has software? by Sparr0 · · Score: 3, Insightful

      And what if I want to add a stopwatch or countdown timer mode to it? Or make it count in an alternate base or time system?

    3. Re:It has software? by X0563511 · · Score: 1

      How can this possibly be offtopic?

      Grandparent is a post saying "using that is overkill" - a direct response to the topic.

      Parent is a post saying "well yes, but what if..." which is a direct response to the direct response.

      It can't get any more on-topic than this! WTF!

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    4. Re:It has software? by Jurily · · Score: 1

      It can't get any more on-topic than this! WTF!

      Needs more car analogies.

    5. Re:It has software? by dangitman · · Score: 1

      So, one component uses some code. How does that make the whole clock open source?

      --
      ... and then they built the supercollider.
    6. Re:It has software? by node+3 · · Score: 1

      So, one component uses some code. How does that make the whole clock open source?

      Here is the source. Just because you don't compile it doesn't mean it's not open source, it just means it's not open source *software*.

    7. Re:It has software? by hot+soldering+iron · · Score: 2, Funny

      Or cowbell.

      --
      When you want something built, come see me. If you want correct grammar and spelling, get a F*ing liberal arts student.
    8. Re:It has software? by ladyada · · Score: 2, Informative

      if you read the design document, schematic and source you'll see theres a lot more in there than just a counter. theres day calculator, date, alarm, low power mode, RTC, HV boost, menu system with configuration, etc etc. a $2.50 microprocessor isnt overkill when you consider its doing -everything- except drive the HV VFD.

    9. Re:It has software? by Anonymous Coward · · Score: 0

      Nice kit but not exactly original. You can find these are all over ebay http://cgi.ebay.co.uk/6-DIGIT-VFD-CLOCK-2-ALARM-IDEAL-GIFT-NIXIE-TUBE-ERA-UK_W0QQitemZ260403291994QQcmdZViewItemQQptZUK_Consumer_VintageAudio_RL?hash=item3ca13ee75a&_trksid=p4634.c0.m14.l1262#ht_4458wt_941 but at least this one is open source

    10. Re:It has software? by Locutus · · Score: 1

      it's an exaggeration of the term "open source" but if you look at the pages linked then you should see what it's said the whole clock is open source.

      LadyAda publishes the circuit schematic as a PNG image file and in the original Eagle data file format. She publishes the board layout and the source code for the micro controller too.

      So what about this not being "open source" do you not get? The source data for everything is open to you.

      LoB

      --
      "Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
    11. Re:It has software? by dangitman · · Score: 1

      That's called a schematic or circuit diagram. It isn't "the source."

      --
      ... and then they built the supercollider.
    12. Re:It has software? by node+3 · · Score: 2, Insightful

      That's called a schematic or circuit diagram. It isn't "the source."

      It's not the source *code*.

      There are "open source" beers and colas. This is in that same vein. Making a big fuss over the word "source" is a bit silly.

    13. Re:It has software? by digitalunity · · Score: 2, Informative

      Open Source has grown beyond just a description of software, it's an ideology too.

      And indeed, if we were talking about Verilog or VHDL, indeed, the "schematic" might just be little different from source.

      --
      You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
  2. Anyone else? by Anonymous Coward · · Score: 0

    Sucking clock? Sorry, couldn't resist.

  3. In Soviet Russia by Anonymous Coward · · Score: 1, Funny

    Time measures you.

    1. Re:In Soviet Russia by Anonymous Coward · · Score: 0

      Hey Ladyada - where the fuck is my x0xb0x kit!? I've been wait listed for over a year now. I think it's actually going to be 2 years now.

      --Time

  4. And this is worth buidling because.. ???? by pearl298 · · Score: 0

    Gee I don't have a digital clock in my house yet ...

    1. Re:And this is worth buidling because.. ???? by Flaming+Cowpie · · Score: 2, Interesting

      Because most people don't the skills needed to actually build it. Go back to your corner.

      --
      Sigs? We don't need no steekin Sigs!
    2. Re:And this is worth buidling because.. ???? by Anonymous Coward · · Score: 3, Funny

      Most people don't the skills to write.

    3. Re:And this is worth buidling because.. ???? by Hal_Porter · · Score: 1

      I think he just accidentally out one word. We hacker genii often use language in a quirky way you neurotypicals don't grokq.

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    4. Re:And this is worth buidling because.. ???? by Opportunist · · Score: 4, Interesting

      Here's a gadget that is cool (from a geek point of view), that you can make yourself (provided you have the skills, you should as a geek), that makes other geeks go "ooooooh" in envy and awe, that glows in flurescent blue (that by itself is already enough) and you dismiss it as something you wouldn't want.

      Please drop your geek card in the shredder by the door on your way out, will ya?

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    5. Re:And this is worth buidling because.. ???? by Anonymous Coward · · Score: 0

      that makes other geeks go "ooooooh" in envy and awe

      If you are a 12 year old kid, assembling this would be a feat. However if you are any older it's just pointless. Why would you envy anybody who assembled a huge digital clock based on blueprints? Sure that was fun when we were kids but at some point you should realise: great I can assemble basic stuff, how about something useful now?

    6. Re:And this is worth buidling because.. ???? by Tetsujin · · Score: 1

      Gee I don't have a digital clock in my house yet ...

      The digital clocks in my house aren't vacuum-fluorescent displays.

      Now, you may be saying, "so who cares about VFDs?" - and from a functional standpoint this is a perfectly valid argument. There's nothing a VFD can do, in terms of practical, display-related functionality, that an LED display cannot do cheaper today. And, in fact, VFDs of any kind have various practical disadvantages - risk of breakage, cathode poisoning, etc.

      What VFDs do offer is a rather unique aesthetic - the quantity and quality of the light, the "glow" of the display. The segments work similarly to neon signs - inert gases charged with electricity until they give off light. It's art, basically. One might want a VFD-based clock for similar reasons why one might want a grandfather clock instead of a cheap wall clock from Staples. Probably the cheap clock is actually going to be better at telling time - but it's not just about telling time. It's about using this "job opening" around your house - the need for a timepiece - as an excuse to put something really cool on display.

      Now, to me personally, using 7-segment displays is simply a waste of time. It's not interesting. If I were to build a VFD clock of some kind I'd want Nixie tubes, which contain electrical contacts inside the tube in the shape of the different numbers. That, to me, would be a much more interesting and worthwhile display piece.

      --
      Bow-ties are cool.
    7. Re:And this is worth buidling because.. ???? by Flaming+Cowpie · · Score: 1

      Actually it's because I'm usually multitasking and thinking ahead to the next thing I'm doing and the fingers don't always keep up with the train of thought. Though, in retrospect, I like your reply better than mine.

      --
      Sigs? We don't need no steekin Sigs!
  5. What's russian about it? by Anonymous Coward · · Score: 0

    It's just a digital clock, aint it?

    1. Re:What's russian about it? by Trepidity · · Score: 1

      I was confused by that also, but it appears it's the particular variety of display tube that's Russian.

      --
      10 PRINT CHR$(205.5+RND(1)); : GOTO 10
  6. building from old parts by Thanshin · · Score: 4, Interesting

    A long time ago I redirected my child interest in destroying and rebuilding electronics to tinkering with virtual constructs.

    So I shouldn't be interested in "hardware hacking"; however, too many hours of fallout, too many zombie movies and too many post apocaliptic novels have given me a degree of interest in that part of the engineering poetry.

    Time to go find an open source rifle made from old car parts.

    1. Re:building from old parts by Unending · · Score: 1

      That would probably be a Sten.

    2. Re:building from old parts by R2.0 · · Score: 1

      Hmmm...

      AC compressor
      Exhaust pipe
      ignition system

      Yeah, I think a spud gun is doable.

      --
      "As God is my witness, I thought turkeys could fly." A. Carlson
    3. Re:building from old parts by Hurricane78 · · Score: 1

      Well, what do you think AK-47s in Afghanistan are made of? My father told me, that they rip(ped) off parts of bombs that did not explode, car parts, etc, and then used a small hammer and fire, to make real working AK-47s out of them. Horribly unprofessional and very impressive at the same time. ^^

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    4. Re:building from old parts by wallsg · · Score: 1

      It should fire rail road spikes and be made from a pressure cooker.

  7. Quite neat, actually. by John+Pfeiffer · · Score: 5, Insightful

    First off, LadyAda is awesome. I really don't need to say any more than that.

    I've been wanting to make something like this for a while now. A year or two ago, I bought a big box of the same old Soviet 'vacuum fluorescent indicator' tubes, but I was always having trouble working out the hardware involved, especially the power supply. Using a boost converter is a great idea which might have occurred to me if I had had any experience with them at the time. (Other projects have since taken priority)

    My enclosure design wasn't quite as...ah, 'conservative' as a nice simple laser-cut plexiglass box though :) http://media.giantpachinkomachineofdoom.com/blog/2008-06/images/clockwip3.png

    Now I'm going to have to take another try at it! :D

    --

    Friend: "The NIC is misconfigured..." Me: "No prob, I'll just telnet in and fix it." *Silence*
    1. Re:Quite neat, actually. by Pentium100 · · Score: 1

      I have made a nixie clock that uses counter chips and not some microcontroller. In any case, to get power for a VFD device you probably need a transformer with 3 outputs or 3 separate transformers. You need the anode voltage (depends on the display, probably 35-70VDC), power for your chips (5-12VDC) and power for the filament (usually 3VAC, it is important that this is AC).

      For my nixie clock I used two 220V/12V transformers. One takes in 220V from the outlet and transforms it to 12V (power for the chips), the other takes the 12V and transforms it back to about 200V.

      The only difficulty I see with VFDs is that hey are common cathode and the counter chips are usually active high so you need two transistors for each element. With nixies you only need one transistor per cathode. On the other hand my nixie clock does not use multiplexing so it has a higher total number of transistors (29).

    2. Re:Quite neat, actually. by DZign · · Score: 1

      I really like this project..

      One thing I'll test (if I ever have time) if the project can be adapted to run on pinball displays..
      Pinball machines in the 80ies also used this type of vacuum displays (Gottliebs had the nice blue ones like shown here), Bally/Stern/Williams had smaller red ones - 6 and 7 digits.

      I have enough of these pinball displays laying around (used ones can be found cheap from parts games on ebay and even new displays are still available from pinball parts shops).. so these are probably easier parts to find than these rare russian displays.
      And what will be cooler in a gameroom than to have a clock made out of pinball displays ?
      (maybe even put it in a fake backbox).

      --
      Learn about pinball machines on www.flippers.be
    3. Re:Quite neat, actually. by bitrex · · Score: 2, Informative

      They're not rare in Soviet Russia! Joking aside, these VFDs are not that rare. Like some kind of state-sponsored labor monster run amuck, these (and all kinds of other vacuum tubes) were produced by the trainload during the heyday of the Cold War. They can now be picked up for a few dollars on eBay from sellers in Russia and the former Soviet republics. Of course the US produced its fair share of tubes as well, but the vacuum tube era seems to have lasted much longer in Eastern Europe than here (particularly in military applications), and lots of the common NOS tubes in the US have been used up in guitar and stereo amps. In the strange world of vintage vacuum electronics it is often the more exotic looking items covered in Cyrillic that are cheap and cheerful, and the US and UK parts that are rare and coveted.

      It would be interesting to know what product these VFD tubes were initially intended for; maybe they were used in calculators given the number of digits. The US pretty much jumped directly from Nixies and Numitrons right to LEDs and LCDs, but I'm betting that in Eastern Europe the adoption of LED technology was more slow and there needed to be a display technology to fill the gap. I think my suspicions may be correct given this eBay aucion where a Russian manufactured VFD clock is for sale - the description says it supposedly was manufactured in 1982 when a similar product in the US would be LED for sure.

    4. Re:Quite neat, actually. by AmiMoJo · · Score: 1

      I would love to know where they are getting that case manufactured. I'm good with the electronics side, but hopeless when it comes to making cases.

      You can get PCBs manufactured cheaply in China now (Seeed Studio are good). For cases though the only real option seems to be people like Front Panel Express who only work with metal. I keep thinking about taking a basic woodworking course or something, but I have arthritis in my hands so it's not that simple.

      You would think that there would be someone doing low volume laser cut panels in plastic or wood, but everywhere I have looked they are either very, very expensive or want minimum quantities of 100 or more. I suppose AdaFruit are lucky in that they can sell lots of kits so it's not an issue.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    5. Re:Quite neat, actually. by zwarte+piet · · Score: 1

      Wicked!!

    6. Re:Quite neat, actually. by PhunkySchtuff · · Score: 2, Informative

      Have a look at Ponoko - they're great for making one-off items, like this case, from all sorts of laser-cut materials. I'm not affiliated with Ponoko, just a happy customer. Looking at the design of the case, if it wasn't laser-cut, it should have been - a case like that would be trivial to get sorted out with the precision of laser cutting...

      --
      Specialist Mac support for creative pros, Melbourne
    7. Re:Quite neat, actually. by Ageless · · Score: 1

      That case is really awesome. Did you ever make the case, or is that just a rendering? I'd love to have that clock on my desk :)

    8. Re:Quite neat, actually. by hjf · · Score: 1

      I'd like to see the circuit for your output driver, can you post it?

    9. Re:Quite neat, actually. by smellsofbikes · · Score: 1

      Boost converters are pretty easy to make, these days. But you can also use a diode/capacitor-based voltage doubler (tripler, quadrupler...) and get to the same place, which is often easier because you don't have to worry about finding a high-voltage switcher or building some sort of accurate voltage divider so a boost converter controller doesn't get fried through overvoltage. You can use LTSpice to model a doubler and make sure it's actually going to be able to produce the voltage/amperage you need with real-world components, as well. Or you could wind your own transformer on a toroid, if you're feeling particularly adventurous.

      --
      Nostalgia's not what it used to be.
    10. Re:Quite neat, actually. by ladyada · · Score: 1

      yes its a cool trick! sadly those circuits work only with AC. if you put DC in you'd be disappointed with the output :) there are DC 'switch cap' converters, they seem to show up in RS232 converters a lot

    11. Re:Quite neat, actually. by John+Pfeiffer · · Score: 1

      Just a rendering for now. Still trying to get my CNC machine built to cut the pieces. EVENTUALLY it will happen. :3

      --

      Friend: "The NIC is misconfigured..." Me: "No prob, I'll just telnet in and fix it." *Silence*
    12. Re:Quite neat, actually. by Pentium100 · · Score: 1

      Very simple: for each cathode you will need a MPSA42 transistor and a 1K resistor. Connect the collector of the transistor to the cathode of the nixie, emitter to ground and base through the 1K resistor to your control logic.

      Here's the schematic: http://img175.imageshack.us/img175/9999/nixie.gif

    13. Re:Quite neat, actually. by Ageless · · Score: 1

      I was trying to find a way to contact you privately but no dice. Anyway, I have a 3 axis CNC mill I've been learning how to use for a few months now. If you are interested, I'd love to cut these pieces out based on your design. Maybe I could make a set for me and one for you, or something. Get in touch if you are interested: jason@vonnieda.org

    14. Re:Quite neat, actually. by smellsofbikes · · Score: 1
      I'd assumed AC input, yeah. I should've said something about that. (Ya can do it with DC but then you've just reinvented the switching boost converter, which might not be what you intended.)

      Switchers that use caps rather than inductors are nice for several reasons, but I've not seen any that can handle higher (over 30VDC) voltage outputs. They may very well exist, but you run into the same issues you do with inductive boosters: you have to find silicon processes that can handle very high voltages, while handling low voltages efficiently, and that's somewhat tricky.

      By the way, thanks for all your hard work. I've used tutorial stuff on your website extensively for projects I've done.

      --
      Nostalgia's not what it used to be.
    15. Re:Quite neat, actually. by hjf · · Score: 1

      that's what I was thinking. does each segment draw more than 20mA? if not, you can forget the transistor and resistor altogether, just hook up the filament to the output pin, if you use Microchip PICs. they can source or sink current.

      anyway you say that you need 3VAC for the filament. how are you driving it? transistors don't work both ways, with that circuit you're rectifying AC. I think you need both an NPN and PNP to make the full-wave go through.

    16. Re:Quite neat, actually. by Pentium100 · · Score: 1

      This was for nixies, nixies do not have filaments, VFDs do and for them, you can get a transformer that outputs 3VAC.

      And you have to use transistors even if the number uses less than 20mA, because when it is unconnected, it has about 100V on it, which I assume the microchip would not like.

      Nixies have a common anode, so it's easy to drive them, VFDs have common cathode, so you need another PNP tranbsistor to provide the voltage.

  8. Cute, but how about this. by lurcher · · Score: 5, Interesting

    IMHO this has more geek points.

    1. Re:Cute, but how about this. by John+Pfeiffer · · Score: 2, Informative

      I don't know, man. The old IV-18 tubes are really wicked looking. You have a cylindrical glass vacuum tube, and inside it is a slab of glass with 7-segment digit phosphors, shiny silver traces, and extremely tiny, thin hexagonal grids infront of each digit. So, it basically looks like a glowing blue digital readout 'suspended' in a thin glass envelope.

      There's also the IV-27 which is larger and 13 digits instead of 8, and the IV-21 (I think it's 21) which is a tiny version of the IV-18.

      --

      Friend: "The NIC is misconfigured..." Me: "No prob, I'll just telnet in and fix it." *Silence*
    2. Re:Cute, but how about this. by Linker3000 · · Score: 1

      That's pretty neat - but, ooooh, I can feel the burn-in from here!

      --
      AT&ROFLMAO
    3. Re:Cute, but how about this. by Spy+Handler · · Score: 1

      Sorry, the green clock may be technically more advanced but it's too big and ugly. The blue Ladyada clock is sleeker and looks VERY cool.

    4. Re:Cute, but how about this. by Anonymous Coward · · Score: 2, Interesting

      IMHO this has more geek points.

      I see your bet, and I raise you one nixie clock built in a bottle.

    5. Re:Cute, but how about this. by Cannelloni · · Score: 1

      That, my good man, is just too cool! How did you find it?

      --
      Beauty is in the beholder of the eye.
    6. Re:Cute, but how about this. by lurcher · · Score: 1

      The place I use to buy parts for tube amps sells a kit of parts. (google Ask Jan First)

    7. Re:Cute, but how about this. by lurcher · · Score: 1

      May be a age thing, it reminded me of the Tek vector graphics terminal I used to use. (and of course asteroids)

    8. Re:Cute, but how about this. by Anonymous Coward · · Score: 1, Interesting

      Too big? You'll be wanting the CRT pocket watch version then.

      http://www.cathodecorner.com/sc60.html

      A little crt tube pocket watch 25mm by 75mm by 100mm. Lovely!

  9. four winds shotgun by Anonymous Coward · · Score: 0

    no need to get fancy with no machine gun, start with single shot first

    1. Re:four winds shotgun by Steauengeglase · · Score: 1

      Get out of here you filthy Lo Tek!

  10. [Oblig.] Yes, but by martas · · Score: 0

    ... does it run Linux?

    --
    weinersmith
    1. Re:[Oblig.] Yes, but by Opportunist · · Score: 1

      In Russian vacuum, Linux runs YOU.... Or something like that.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  11. I wanna buy one... by Anonymous Coward · · Score: 0

    Serious...

    Building it would take time i don't feel like using to do this. And relearning skills i've let slip by choice.

    But damm. That would look sharp for the entertainment center.

    Anyone know where to get one like the one pictured? Or close.. Nice sharp clean lines and simply a clock. One not suffering from feature creep like most alarm clocks.

  12. Not so retro by OrangeTide · · Score: 1

    Looks like the clock on my mom's 15 year old oven. Also looks like the display on a 10-15 year old VCR. If a teenager could remember it being new, then it's not retro. Sorry.

    Cool project though.

    --
    “Common sense is not so common.” — Voltaire
  13. bad-ass! by X0563511 · · Score: 1

    That is one bad-ass looking display. I didn't even know these existed... and I can see now that I would want to use them over normal LCD or LEDs, when given the space and power to use them. That looks fantastic!

    Stick a color filter over it for even more badassery!

    --
    For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
    1. Re:bad-ass! by Tetsujin · · Score: 1

      That is one bad-ass looking display. I didn't even know these existed... and I can see now that I would want to use them over normal LCD or LEDs, when given the space and power to use them. That looks fantastic!

      Stick a color filter over it for even more badassery!

      The 7-segment ones strike me as rather boring - though admittedly I haven't seen 7-segment fluorescent in person before...

      Nixie tubes or (for more general applications) dot-matrix VFDs seem more appealing to me...

      --
      Bow-ties are cool.
  14. 0.002% Accuracy means... by Anonymous Coward · · Score: 0

    it's wrong 99.998% of the time?

    assuming it means 99.998% accuracy, that means it skews by 2 seconds a day.. not that great IMO.

    Well, just nitpicking, would still love to have one of them.

    1. Re:0.002% Accuracy means... by Anonymous Coward · · Score: 0

      0.002% = 20ppm, which is a bog standard crystal.
      A decent precision watch crystal has <2ppm, giving ~1.2sec/week.
      I'd probably just add a radio clock receiver, also removes the need for set buttons.

    2. Re:0.002% Accuracy means... by ladyada · · Score: 1

      Ha! good luck adding a radio receiver to a clock with both a multiplexed display and 32khz boost converter. WWVB receivers wont work within 10 feet of this clock. (yes, we've tried it)

    3. Re:0.002% Accuracy means... by Tetsujin · · Score: 1

      Ha! good luck adding a radio receiver to a clock with both a multiplexed display and 32khz boost converter. WWVB receivers wont work within 10 feet of this clock. (yes, we've tried it)

      Interesting.

      How about GPS? Is it likewise afflicted with interference?

      --
      Bow-ties are cool.
  15. does everything need the open source buzz word? by Anonymous Coward · · Score: 0

      Nixie kits have been around for years, why now does it need the open source buzz word attached to it? Most electronic magazines will always include source for projects they list. They don't go around saying 'hey look at the open source article we wrote'

      These are great projects for the youngsters, nothing like remembering how you almost/did get the living shit shocked out of you. High voltage is fun for the whole family.

  16. or... by lxs · · Score: 3, Insightful

    You could just rip the clock out of an old VCR.

    1. Re:or... by Anonymous Coward · · Score: 1, Funny

      Sure, but why would you want a clock that only flashes "12:00"?

  17. Since when are nixies "high voltage"? by jcr · · Score: 1

    It's been a long time since I checked, but as I recall nixies only took 100v or so.

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
    1. Re:Since when are nixies "high voltage"? by iamdrscience · · Score: 1

      I dunno, as an electronics hobbiest, I generally consider "high voltage" to be any power source that would be dangerous to lick. 5V TTL? No problem. 9V battery? Fairly uncomforable. 18V power supply? Not dangerous, but uncomfortable enough that I wouldn't lick it more than once (and haven't). 120V-180V leading to a Nixie? High enough that I'm not going to try.

      I understand the standard may be different in industry.

    2. Re:Since when are nixies "high voltage"? by unitron · · Score: 1

      It's been a long time since I checked, but as I recall nixies only took 100v or so.

      170V DC

      --

      I see even classic Slashdot is now pretty much unusable on dial up anymore.

    3. Re:Since when are nixies "high voltage"? by Anonymous Coward · · Score: 0

      1) 9V - nice metaly taste
      2) 12V - mostly the same
      3) Car spark plug - numb face for 30 min.
      4) 220 - a hole in the tongue for a month.

      3 and 4 happened by accident.

    4. Re:Since when are nixies "high voltage"? by jcr · · Score: 1

      I generally consider "high voltage" to be any power source that would be dangerous to lick.

      I draw that line at voltage that will arc through a rubber-coated canvas glove.

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    5. Re:Since when are nixies "high voltage"? by Viol8 · · Score: 1

      How can you accidentaly lick a live spark plug FFS???

  18. My turn! by Anonymous Coward · · Score: 0

    I made this rather un-arty little project:
    http://d.furaffinity.net/art/vylbird/1228053352.vylbird_01010020.jpg
    And, because it's appearance isn't as good as I'd like, I more recently built this replacement:
    http://vyl.avians.net/misc/Glowydie2.jpg

    Electronic dice. The second one is configurable d6/12/20/100.

  19. 0.002% accuracy? by Arancaytar · · Score: 1, Informative

    I hope that is the error, not the accuracy. :P

    For a self-built clock, losing 1.728 seconds a day isn't too bad. But it's not that great either...

  20. But..... by thephydes · · Score: 1

    ....does it blend?

  21. Glowing tubes, mmm! by Suomi-Poika · · Score: 1

    I ordered it immediately after I saw the first picture. I have a nixie clock kit which has been laying half assembled for years. I haven't connected the tubes and I don't have a case for it. Now I get a complete kit where from I can copy some designs, what a bargain! Thank you LadyAda!

  22. "Open Source" hardware by dangitman · · Score: 3, Insightful

    I'm not sure that the "Open Source" moniker has any relevance to hardware projects like this. In software, the "source code" is the actual raw material that a complied application is made of. In hardware, the "source" is physical electronic components.

    I guess you could call the freely-available plans and schematics "the source" but that doesn't make much sense, because without hardware components, you can't compile it into a working device. So the term doesn't really apply, especially as we've had freely available electronic schematics for decades, and nobody ever called them "open source." This terminology just seems to be a way to seem cool and trendy.

    --
    ... and then they built the supercollider.
    1. Re:"Open Source" hardware by SlashWombat · · Score: 2, Interesting

      Truth is, how much simpler can electronics (and programming) get than a clock ... The basic "algorithm" once you get your reference frequency low enough (... generally 1 Hertz) is -> divide by 60 = seconds, divide by 60 = minutes, divide by 12 (or 24 if you prefer) = hours. Using a micro, you put the divides in an interrupt routine. You can chose to display at the end of the interrupt, or in the main loop.

      I have seen (smart) 12 year olds build digital clocks using the relevant TTL/CMOS dividers, with the displays being either LED or Nixie tubes. (The difference between LED or Nixie is in the type of display driver chip.)

      However, I wish the authors well. Don't see many people building anything electronic these days, probably because the price of consumer electronics is way lower than the price of just the parts! (IE: DVD player for under $20 is just one common item ... couldn't even make the case for that in any western country.)

    2. Re:"Open Source" hardware by Max+Romantschuk · · Score: 5, Insightful

      I respectfully disagree.

      RMS himself, the holy fanatic of free software, has compared swapping code to swapping recipes for cooking.

      Open source and by extension free software is about unrestricted access to the instructions for making something. If this something is a computer program, a piece of hardware, a meal, a knitted sweater or a bottle rocket is irrelevant.

      Granted, the term open source as understood by this community is most often applied to software. But the open source model can be successfully applied to any instructions that can be shared and improved upon. I dare you to dig a little, there is a lot more of this "open source" stuff out there than software.

      --
      .: Max Romantschuk :: http://max.romantschuk.fi/
    3. Re:"Open Source" hardware by dangitman · · Score: 1

      I dare you to dig a little, there is a lot more of this "open source" stuff out there than software.

      I'm well aware of it, I spent my teen and pre-teen years building electronics from freely-available plans. But we never called it "open source" back then, so why start now?

      Likewise, with your RMS example, nobody calls swapping recipes "open source," it's just swapping recipes, or "cooking."

      --
      ... and then they built the supercollider.
    4. Re:"Open Source" hardware by Anonymous Coward · · Score: 0

      RMS himself, the holy fanatic of free software, has compared swapping code to swapping recipes for cooking.

      Open source and by extension free software is about unrestricted access to the instructions for making something.

      Hi Max Romantschuk,

      You appear to be discussing "open source" and "free software" as if they were the same movement.

      The official definition of "open source software" (which is published by the Open Source Initiative and too long to cite here) was derived indirectly from our criteria for free software. It is not the same; it is a little looser in some respects, so open source supporters have accepted a few licenses that we consider unacceptably restrictive of the users. Nonetheless, it is fairly close to our definition in practice.

      However, the obvious meaning for the expression "open source software" is "You can look at the source code," and most people seem to think that's what it means. That is a much weaker criterion than free software, and much weaker than the official definition of open source. It includes many programs that are neither free nor open source.

      Since that obvious meaning for "open source" is not the meaning that its advocates intend, the result is that most people misunderstand the term. Here is how writer Neal Stephenson defined "open source":

              Linux is "open source" software meaning, simply, that anyone can get copies of its source code files.

      I don't think he deliberately sought to reject or dispute the "official" definition. I think he simply applied the conventions of the English language to come up with a meaning for the term. The state of Kansas published a similar definition:

              Make use of open-source software (OSS). OSS is software for which the source code is freely and publicly available, though the specific licensing agreements vary as to what one is allowed to do with that code.

      The New York Times has stretched the term to refer to user beta testing -- letting a few users try an early version and give confidential feedback -- which proprietary software developers have practiced for decades.

      Open source supporters try to deal with this by pointing to their official definition, but that corrective approach is less effective for them than it is for us. The term "free software" has two natural meanings, one of which is the intended meaning, so a person who has grasped the idea of "free speech, not free beer" will not get it wrong again. But "open source" has only one natural meaning, which is different from the meaning its supporters intend. So there is no succinct way to explain and justify the official definition of "open source." That makes for worse confusion.

      In conclusion, as the advocates of open source draw new users into our community, we free software activists have to work even more to bring the issue of freedom to those new users' attention. We have to say, "It's free software and it gives you freedom!" -- more and louder than ever. Every time you say "free software" rather than "open source," you help our campaign.

      Thanks,
      Robo-RMS

    5. Re:"Open Source" hardware by zwarte+piet · · Score: 1

      Ah yes, In those days Philips used to include the schematics of their radio's. I made my own by using their schematics.

    6. Re:"Open Source" hardware by Ephemeriis · · Score: 1

      I'm not sure that the "Open Source" moniker has any relevance to hardware projects like this. In software, the "source code" is the actual raw material that a complied application is made of. In hardware, the "source" is physical electronic components.

      I guess you could call the freely-available plans and schematics "the source" but that doesn't make much sense, because without hardware components, you can't compile it into a working device. So the term doesn't really apply, especially as we've had freely available electronic schematics for decades, and nobody ever called them "open source." This terminology just seems to be a way to seem cool and trendy.

      So, what can you do with the source code to a piece of software if you have no hardware? If someone just hands you a stack of paper with source code printed on it, and you've got no computer to run it on, what good is it?

      Or maybe we're the hardware. Source code is instructions that tell hardware what to do... These are instructions that tell us how to build a clock... Not much different from the control programs that run industrial robots.

      Regardless, I think the term applies. OSS is about the freedom to distribute and modify source code. These instructions are available for modification and distribution - unlike the instructions on how to build the RCA clock/radio I've got sitting on my bedstand. Someone else out there might take these instructions and expand upon them by adding an AM/FM tuner or something.

      --
      "Work is the curse of the drinking classes." -Oscar Wilde
    7. Re:"Open Source" hardware by KFW · · Score: 1

      I spent my teen and pre-teen years building electronics from freely-available plans. But we never called it "open source" back then, so why start now?

      Um, because we have a good general purpose term for it now that wasn't in use when you were a pre-teen? /K

    8. Re:"Open Source" hardware by Anonymous Coward · · Score: 0

      Open source means sharing their thoughts without anything in return. The "source" is the "intellect" involve in making some physical/virtual things work for a purpose.

    9. Re:"Open Source" hardware by NixieBunny · · Score: 1

      You wouldn't say that if you've ever tried to understand or repair an item for which all that documentation is not available.

      There has also been open source software for decades, but it wasn't called open source either. It was called a user library.

      --
      The determined Real Programmer can write Fortran programs in any language.
    10. Re:"Open Source" hardware by ladyada · · Score: 1

      if it was just a timer divider, it would be a rather boring clock! if you read the design document, schem or source code you'll see theres a lot more in there than just a counter :)

    11. Re:"Open Source" hardware by Tetsujin · · Score: 1

      I spent my teen and pre-teen years building electronics from freely-available plans. But we never called it "open source" back then, so why start now?

      Um, because we have a good general purpose term for it now that wasn't in use when you were a pre-teen? /K

      Because it explicitly conveys the notion that in addition to having open access to this (copyrighted) circuit design information, you also have a degree of freedom in how you may use it?

      --
      Bow-ties are cool.
    12. Re:"Open Source" hardware by dangitman · · Score: 1

      No, it's a very poor general-purpose term, because it dilutes the meaning of "open source" in software. We already have plenty of perfectly good terms for homebrew electronics, so why do we need to misuse this term?

      --
      ... and then they built the supercollider.
    13. Re:"Open Source" hardware by dangitman · · Score: 1

      Because it explicitly conveys the notion that in addition to having open access to this (copyrighted) circuit design information, you also have a degree of freedom in how you may use it?

      But when was that ever not the case?

      --
      ... and then they built the supercollider.
    14. Re:"Open Source" hardware by dangitman · · Score: 1

      You wouldn't say that if you've ever tried to understand or repair an item for which all that documentation is not available.

      Yes I would, and yes I have.

      Documentation is not the same thing as "open source" it's documentation. By this logic, my DVD player is Open Source, because it comes with documentation in the form of a user manual.

      --
      ... and then they built the supercollider.
  23. Oh come on, get a clue. by Viol8 · · Score: 2, Insightful

    I had a digital watch in 1979 that could do a stopwatch and day of the week. Do you honestly think it had a programmed CPU in it? It was all hardwired TTL logic on a single chip. You can do quite a lot with hardware alone - ask the creators of Pong.

    1. Re:Oh come on, get a clue. by Norwell+Bob · · Score: 1

      Mod this guy up... he's absolutely correct and to mod him a "troll" is just ignorant.

    2. Re:Oh come on, get a clue. by Thoughts+from+Englan · · Score: 2, Informative

      Fair point but the beauty of using a microcontroler is that you can reconfigure the system to specific needs without having to redesign the hardware every time. This is pretty much what microprocessors were intended for until various people thought "Hey I can make a general purpose machine out of these"

      --
      That was supposed to be "Thoughts from England" ... Oh well.
    3. Re:Oh come on, get a clue. by Anonymous Coward · · Score: 0

      You can do quite a lot with hardware alone - ask the creators of Pong.

      Software is just more-easily-variable hardware schematics. The maths aint different.

      The cost of a microprocessor is totally insignificant for a project like this.

    4. Re:Oh come on, get a clue. by Cid+Highwind · · Score: 2, Insightful

      Microcontroller? about a buck
      Open source clock firmware? free
      1970s era TTL clock chips? good luck finding those (and the displays they're designed to drive) on eBay...


      You can do a lot with hardware alone, it's just not usually an efficient use of time, board space, power, or money anymore.

      --
      0 1 - just my two bits
    5. Re:Oh come on, get a clue. by Cassini2 · · Score: 1

      Most of those old digital watch chips used a surprisingly microprocessorish architecture, and MOS (maybe even CMOS). I can almost guarantee that chip was not done with standard TTL, or even LSTTL. Your watch probably borrows from the 4004 type pre-computer architectures floating around at the time.

      There are two big reasons why a standard TTL architecture is not the way to go. Firstly, TTL consumes a great deal of power, which isn't optimal for a watch.

      The second reason to use a CPU-style architecture is that the LCD and/or LED (for really old digital watches) displays are multiplexed. You could build a full multiplexer to drive the displays, or your could use a data-bus like architecture. Once you have a databus, then it becomes a question of how you want to increment/decrement the counters, and if a central 4-bit adder is better than a series of counter chains floating around the chip. Either way, the counters are going to be registers, and the data will be multiplexed on the data bus to drive the LCDs. For programming, several AND-OR logic circuits are required to do the BCD counting arithmetic, the BCD to seven segment decode functions, and the function sequencing. We could discuss if the design merits the full "programmed CPU" designation, but the design will have enough stuff to look surprisingly like an early computer/counting machine/calculator design.

    6. Re:Oh come on, get a clue. by COMON$ · · Score: 1

      Exactly, any CS or engineering student (let alone a professional) worth their salt can build a clock with nothing but a breadboard capacitors and a couple nand gates.

      --
      CS: It is all sink or swim...oh and did I mention there are sharks in that water?
    7. Re:Oh come on, get a clue. by Viol8 · · Score: 1

      "Firstly, TTL consumes a great deal of power, which isn't optimal for a watch. "

      CPU cores in those days weren't exactly known for their frugality. And most ran on 5V , not the 1V available from a watch battery.

      What you describe I'm sure was possible but the watch I had was one of the very first that followed the LED generation of watches. I very much doubt it had anything approaching a 4004 in it - why embed 10K transistors to create a CPU core when you can get away with a tenth of that using hard wired logic? To use my other example - compare the number of transitors required to make pong , then compare that with the number that pong would have required if it had been built around a CPU. Of course the law of diminishing returns applies and at some level of functionality hard wiring would require more components but a watch isn't that level.

    8. Re:Oh come on, get a clue. by Cassini2 · · Score: 1

      I just finished looking at a paper on the subject from 1972. In 1972, wrist watches were already using special bipolar transistor circuits for low power consumption. Standard TTL was unsuitable for the application. There was already a widespread drive to switch to CMOS, starting with RCA in 1967.

      The first early LSI watch chip was an Intel 5810 CMOS chip, and it is likely that is the chip in your 1979 LED wrist watch. Specifically, the Intel prototype boards used LEDs as the display for this chip.

      Given the chip comes from Intel, the inventors of the 4004, it is likely that there are at least some subtle design queues taken from the other Intel products. Simply put, the architecture of a wrist watch design, specifically the multiplexed displays, really lends itself to a certain type of solution that resembles a computer design. A central data bus connecting the registers/counters saves transistors in the overall design.

  24. Yeah , but "Open Source" is a trendy right-on term by Viol8 · · Score: 1

    at this moment in time , and goes down well with the we-hate-MS-stallman/linus/raymond[delete as applicable]-is-god fanboys which is what you need to get a story posted on slashdot.

  25. Trying to get hold of the parts is difficult by Viol8 · · Score: 1

    Back in the 80s you could walk into a Tandys (Radioshack in the states) and just buy components. Now all the Tandys are gone and Maplins has hardly any components in store - you need to mail order everything which is a bit off putting for people who just want to dabble. Well, IMO anyway.

  26. Which brings me to the question... by CarpetShark · · Score: 4, Funny

    The vacuum fluorescent tubes aren't as dangerous as (high-voltage) Nixie tubes

    Why not? Can nothing be done to correct this?

  27. What's so dangerous about nixies? by croftj · · Score: 1

    Sheesh a hacker who is afraid of 170V at low current, is a wimp. If the PS is properly designed to NOT be a bug zapper, then it may tingle, but it will hardly hurt you. Under the best circumstances if it can put out more than 50MA it is way overkill for a nixie clock. Even 20MA gives plenty of headroom.

      You want to see a real neat clock, checkout http://www.nixieneon.com./ I haven't touted it as Opensource, but the code is GPL. It does come with complete schematics and a good assy manual.

    --
    -- Many men would appreciate a woman's mind more if they could fondle it
    1. Re:What's so dangerous about nixies? by zwarte+piet · · Score: 1

      Jeez, my wall socket does 240Volts @ 16 amps and that hasn't managed to kill me. And it tried many times.

  28. Over half the "female" geeks are men by Anonymous Coward · · Score: 2, Funny

    Has anyone else noticed that actual female geeks are outnumbered by trannies? linuxchix.org is all ex-men, not an actual born woman as far as the eye can see. Yeah, that's how to fix gender imbalance: declare the men as women. And you thought it was a const, not a variable.

  29. Upgrade time? by maroberts · · Score: 1

    Looks like the clock on my mom's 15 year old oven. Also looks like the display on a 10-15 year old VCR
    Sounds like an excuse for the oven or microwave to "malfunction" so you can scavenge it for parts....

    --

    Donte Alistair Anderson Roberts - hi son!
    Karma: Chameleon

    1. Re:Upgrade time? by OrangeTide · · Score: 1

      Then how will my Mom bake me pie?

      --
      “Common sense is not so common.” — Voltaire
  30. Wheres the nuke? by bl8n8r · · Score: 2, Funny

    I wonder what happened to the nuke that was sitting behind the timer.

    --
    boycott slashdot February 10th - 17th check out: altSlashdot.org
  31. Oh Cool by Anonymous Coward · · Score: 0

    VFD aren't very cool, they are everywhere and you can find them in everything from cars and calculators and stereos made from the late 70's.

    Sorry they just aren't as cool as Nixies.

    I will continue to watch ladyada.net for more leet hax, i mean, obvious applications of commodity parts.

  32. when you absolutely need to.. by el_tedward · · Score: 1

    Has this guy by chance made a guide on how to construct a jetpack velociraptor with scissors?

    1. Re:when you absolutely need to.. by Anonymous Coward · · Score: 0

      Has this guy by chance made a .......

      from what I understand the guy is actually a girl - ladyada = Lady Ada

  33. Russian precision..... by Anonymous Coward · · Score: 0

    In russia people are way more laid back...
    http://www.ladyada.net/make/icetube/ --> Precision watch crystal keeps time with 0.002% accuracy!

  34. A few glitches in the vodka by Ancient_Hacker · · Score: 1

    Nice looking clock, but:

    Using a microcontroller to supply the BOOST clock is a poor idea. If the software stumbles and leaves the BOOST line high, you have a dead short across the power supply.

    Perhaps fortunately, this might drag the power to the CPU low enough to cause it to reboot, which might restore operation. Or the low voltage might cause it to hang.

    Sometimes good old hardware is the right solution.

    1. Re:A few glitches in the vodka by ladyada · · Score: 2, Informative

      the PWM is hardware controlled and there's a WDT its as reliable as any 'off the shelf' chip...even 555's latch up if set up wrong ;)

    2. Re:A few glitches in the vodka by Ancient_Hacker · · Score: 1

      Pardon me, but is not the PWM software controlled?

      And what happens if:

      (1) The initialization code gets hung up for some reason before the PWM is programmed? You're okay if the outputs unconditionally default to LOW, but if they default to high or tri-state, kaboom.

      (2) What if the code goes off into the boonies and starts executing random code? I've had this happen where the random code just happened to have some "write to interrupt controller and disk" op codes! Lost everything. But at least I did not start a fire.

      Having done more than a bit of real-time programming, I've learned that it's a bad idea to start something in software that you had better be able to finish or something very bad happens.

      One-sixth of a schmitt trigger and one resistor and one capacitor make a simple, totally bulletproof and unhangable oscillator. That would be a much better choice IMHO.

    3. Re:A few glitches in the vodka by ladyada · · Score: 2, Informative

      it is firmware controlled but its set once, its not like an interrupt has to go off at the exact right time. AVRs are pretty good about not freaking out as long as you have BOD set and a WDT (which it does). also, to make the clock display brightness adjustable you cant just use an RC oscillator...how would you set the PWM duty cycle? could it *possibly* screw up? sure. just like logic chips sometimes die or glitch. but its not medical equipment, theres no interlocks, its a DIY desk clock kit in a plastic enclosure.

    4. Re:A few glitches in the vodka by Anonymous Coward · · Score: 0

      That's what watchdogs are for, maybe?

      I didn't RTFA, but many micros have timers, and usually the timers will operate whether the software does or not, barring outright corruption of timer configuration registers by "wandering" software. I'd use a timer output for that. My most recent experience is on Z8 Encore!, and there you can even overclock it to a point where the core goes haywire and doesn't properly execute code anymore, but the timer is still working, with its config registers intact.

      The software for such a clock, if properly implemented, can be rather easily formally proven not to ever stumble. You can run a simplistic VM (a small state machine, really) to manage the clock's operation. Then all you have to show is that the VM won't mess with timer registers no matter how shitty the state table is, and you're done. This is not rocket science, really.

    5. Re:A few glitches in the vodka by bitrex · · Score: 1

      Adding basic overcurrent protection to the boost converter would be a pretty easy mod that might address what Ancient Hacker is talking about - a current sense resistor in series with the switching transistor and an optocoupler could be used to pull down the drive line to ground if the BOOST line gets stuck high. There would have to be a current limiting resistor in series with the BOOST line, which wouldn't be a problem as a FET is being used as the switching device. This would also provide some measure of output overcurrent protection as the average current through the inductor and FET tracks the output current.

    6. Re:A few glitches in the vodka by Ancient_Hacker · · Score: 1

      It's thinking like this that gets my ulcer going.
      What happens if:

            You substitute a "compatible" microprocessor which just so happens to have been "enhanced" with the option to tri-state the I/O lines on powerup?

              Your cat brushes against the acrylic case and sets off a 5500V static discharge, toggling one bit of the PC?

      A nearby lightning strike sends a glitch down the AC line and by capacitive coupling toggles a bit in a register.

      A drunk driver hits a power pole three miles away and the AC power glitches for just long enough to drop the supply voltage to scramble a register.

          A weak cosmic ray strikes the chip, toggling some register bits.

      --------------

      Is the reasonable response to any of these events a dead short across the power supply, smoke, and possibly fire?

      Cmon folks, try thinking just a teensy bit outside of "the CPU and program can never goof up" box.

    7. Re:A few glitches in the vodka by ladyada · · Score: 1

      ancient hacker, the chip has a 'always on WDT' and the only place the dog is kicked is a function where we also set the timer & port registers fresh. if a register freaks out, say the one that has the port direction or the PC, then either the dogkicker will be called (and reset the registers) every 2 seconds OR the chip is completely latched in which case the WDT will reset the chip. same with the BOD, which cuts in at 1.8V (the chip can run down to 1.8V) however, there is -always- a possibility for cosmic waves, so our design accomdates a pulldown to the fet gate and a 200mA 0.1 polyfuse after the DC jack. all shipping kits have this (we'll update the schem shortly). experimenting with wreaking havoc on the FET and causing a dead-short, the fuse kicks in and 'stabilizes' below the rated DC current for the inductor and FET. thanks for helping us think about all this again, if you're still reading this send us a note support@adafruit and we'll send you out a kit once we ship the first round of orders out.

    8. Re:A few glitches in the vodka by Ancient_Hacker · · Score: 1

      Thanks for the reply. It's heartwarming to see a company responding to potential customers.

        You might consider a less fatal solution that does not involve the irreversible blowing of expensive fuses:

      Between the BOOST output from the microprocessor and the gate of the MOSFET, put a 0.01uF capacitor in series, and a 100K ohm resistor from gate to ground. Total cost: about 15 cents. (The cheapest fuse I can find costs a bit more than that.)

          With this kind of AC coupling, the ONLY way the MOSFET can get turned on is if the micro puts out a positive-going edge. The RC time constant is about 1/1000 of a second, so even if the output gets stuck high, the gate will go low within a millisecond.

      Sometimes those old analog components are real lifesavers!

      Regards,

      A_H

    9. Re:A few glitches in the vodka by Anonymous Coward · · Score: 0

      You might consider a less fatal solution that does not involve the irreversible blowing of expensive fuses:

      The OP said "polyfuse". These are self-resetting polymer fuses, not irreversible devices. Example: http://www.circuitprotection.com/polyswitch.asp

      Once one of these trips, disconnect power for a while and it will reset itself. No circuit repair required.

      With this kind of AC coupling, the ONLY way the MOSFET can get turned on is if the micro puts out a positive-going edge. The RC time constant is about 1/1000 of a second, so even if the output gets stuck high, the gate will go low within a millisecond.

      Um, I'm afraid you just defeated the pulse-[b]width[/b] modulation. Your idea might work fine if it was frequency modulation, but from thread context it isn't.

    10. Re:A few glitches in the vodka by Ancient_Hacker · · Score: 1

      >The OP said "polyfuse". These are self-resetting polymer fuses, not irreversible devices. Example: http://www.circuitprotection.com/polyswitch.asp [circuitprotection.com]

      I guess my brain refused to see "polyfuse", because it's a very ridiculous solution, for many reasons:

      (1) Those devices are thermal-- which means it takes a considerable fraction of a second for it to ramp up in resistance. The microprocessor can't tolerate power dips for more than a microsecond or so, so this solution is about half a million times too slow.

      (2) PTC's are expensive-- like 60 cents in quantity.

      (3) At best this is a band-aid-- it does not prevent the problem, it just keeps a fire from starting.

      >Um, I'm afraid you just defeated the pulse-[b]width[/b] modulation.

      Nope. I chose the time constant so it will faithfully pass any PWM going on. I'm assuming they're using a typical PWM frequency of 5 to 50 KHz. If it's below that, which is unlikely, one would trim the resistor value upwards.

      BTW there is one possible issue with my R/C solution, where if it runs at an extreme duty cycle, might require one more 4 cent component. Funny that you have not mentioned that, being a PWM expert and all.

    11. Re:A few glitches in the vodka by ladyada · · Score: 1

      We decided on going with a PTC because it protects the entire circuit. So, even if by some assembly error the FET was pinned high, the PTC would not pass more current than the FET and inductor are rated for at continuous DC. And PTCs are pretty cheap nowadays, ~20 cents each. :)

  35. What's really awesome ... by SpooForBrains · · Score: 1

    ... to me anyway, is not just the project itself, but the sheer care taken with the instructions. There's no assumption that you know anything, which for someone like me - who last did electronics at school some 16 years ago - makes this project actually doable.

    --
    "The dew has clearly fallen with a particularly sickening thud this morning"
    1. Re:What's really awesome ... by Anonymous Coward · · Score: 0

      If you're interested in more electronics projects with detailed explanations, take a look at the NerdKits tutorials, which have been featured many times before on Slashdot (DIY Sound Level Meter, Hackable Microcontroller-Powered Valentines Day Card, iPhone-controlled R/C car, and others).

  36. Low-power RTC by lemaymd · · Score: 1

    It's funny that in a clock centered on a massive vacuum tube they highlight their low-power RTC! Amdahl's law...

    1. Re:Low-power RTC by ladyada · · Score: 2, Informative

      Yup! If you look at the schematics or design document you will see how this works - its described in detail there but basically: If power is unplugged, the microcontroller kills the display and runs at 50uA off of a coin cell for a couple of weeks until power is restored. the low power RTC is used when theres a blackout or the clock is moved, etc. Its a big pet peeve, all clocks should do this!

    2. Re:Low-power RTC by lemaymd · · Score: 1

      Ah, that is a cool feature! That is the most amazing-looking clock I've ever seen, btw. Nice work!

  37. Wait, these are retro now!? Awesome! by Lemming+Mark · · Score: 1

    When I went away to university in 2000, I intended to use my digital wristwatch as an alarm clock. My Dad insisted that I should have something more substantial to wake me up - as a result I inherited his old bedside clock from ... the 80s, perhaps? Ancient, huge, unsubtle - one of its most noticeable features was a glowing digital display that was clearly not LED based. I had rather assumed it was some sort of fluorescent display but I've never seen another one like it. Looking at this clock the display is quite obviously the same stuff. So my ancient alarm clock has now become cool?! Awesome! Only trouble is that it broke a couple of years ago, so I don't get to ride the retro wave :-(

    A shame, since the continuous, vicious sawtooth soundwave it produced instead of a "beep beep" could be heard from other floors in the building and would continue without a break for upwards of 30 minutes if you didn't wake up and hit the thing. For years that had me bolt fully awake in an instant with my fight-or-flight reflexes fully primed, wondering what the awful noise was and ready to sprint to lectures. They don't make 'em like they used to.

    I feel old now!

  38. Here's the Mad Libs version by Profane+MuthaFucka · · Score: 1

    I had a _______ in 1979 that could do a _______ and _______. Do you honestly think it had a programmed CPU in it? It was all hardwired _______ on a single _____. You can do quite a lot with ______ alone - ask the creators of _____.

    --
    Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
    1. Re:Here's the Mad Libs version by Anonymous Coward · · Score: 0

      I had a _booger_ in 1979 that could do a _fart_ and _barf_. Do you honestly think it had a programmed CPU in it? It was all hardwired _butt_ on a single _cootie_. You can do quite a lot with _snot_ alone - ask the creators of _poo_.

  39. Where is the timing input for GPS/NTP? by Anonymous Coward · · Score: 1

    In this day and age, the ability to use an external reference time source would seem important. Sparkfun make a nice board to drive an LCD clock that has an on-board GPS module and I am building a clock based on that now. If this clock had that, I'd buy the kit in a heartbeat.

  40. OpenSourceRussianVacuumFluorescentTubeClocks! by RevWaldo · · Score: 1

    Open Source Russian Vacuum Fluorescent Tube Clocks!
    Open Source Russian Vacuum Fluorescent Tube Clocks!
    Open Source Russian Vacuum Fluorescent Tube Clocks!

    Hi, I'm Al Hvorostovsky, President and CEO of Al Hvorostovsky's Open Source Russian Vacuum Fluorescent Tube Clock Emporium and Warehouse! Thanks to massive Soviet-era overproduction, I am now currently overstocked on Open Source Russian Vacuum Fluorescent Tube Clocks, and I am passing the savings on to you!!!

    Create that retro look in your living room! Makes a great night lite for the baby's room!* A great gift for steampunks! "Hunt for Red October" re-enactments! Have an EMP-proof clock for your bomb shelter! Whatever your Open Source Russian Vacuum Fluorescent Tube Clock needs are! So come on down to Open Source Russian Vacuum Fluorescent Tube Clock Emporium and Warehouse! Just of the main road in Chernyshevsk.

    *Keep out of the reach of children and pets.

    --
    Prisencolinensinainciusol. Ol Rait!
    1. Re:OpenSourceRussianVacuumFluorescentTubeClocks! by ae1294 · · Score: 1

      Have an EMP-proof clock for your bomb shelter!

      Sadly I don't believe this clock would be EMP-proof :-(

  41. Did this in EE291 in like, 1986 by slyborg · · Score: 1

    I'm really perplexed why making an ancient VFD clock is on the first page of /. I mean, cute project, but I could see this in Make or something, not here.

  42. it's nice but by Anonymous Coward · · Score: 0

    can it do twitter??

  43. Who wants to build me one? Contract bids? by popo · · Score: 1

    I'm serious. I dig it. And I have zero (hardware/electronics) technical capabilities. Anyone want to put a pricetag on a custom built one?

    Bids?

    --
    ------ The best brain training is now totally free : )
  44. The all tube digital clock. by Animats · · Score: 4, Interesting

    That's not retro; it has a CPU in it. Look at this all vacuum tube digital clock where all the logic is tubes. 103 tubes.

  45. Oh my by Anonymous Coward · · Score: 0

    That is the best joke ever ! I almost peed myself laughing. Keep them coming, they are so fresh and original.

  46. In Soviet Russia, the clock protects you (really!) by D4C5CE · · Score: 1
    From TFA:

    Clear plastic enclosure protects clock from you and you from clock

  47. Site Layout by ae1294 · · Score: 1

    Just clicked on the main site and was somewhat surprised by the layout. I don't think I've ever seem someone use that pattern for a website before.

    Needless to say, It's been bookmarked for later dissection...

    ... Props all around to Ladyada ...

    1. Re:Site Layout by etherelithic · · Score: 1

      It's based off the Sephirotic Tree of Life. I blame too much evangelion for this sort of knowledge.

    2. Re:Site Layout by ae1294 · · Score: 1

      It's based off the Sephirotic Tree of Life. I blame too much evangelion for this sort of knowledge.

      I'm aware of its origin as well as the many other places one might come into contact with it, except, I really wasn't aware that it was being popularized in cartoons, err I mean Anime....

      Wasn't really looking to discuss that stuff here on slashdot for obvious reasons...