Re: [neonixie-l] Re: 14-digit nixie calculator project with clock function
Hello, I have been thinking about having a stab at a nixie calculator myself! My stumbling block was the keys (specifically, the key caps). What is your source for these? On Monday, 3 October 2022 at 08:58:58 UTC+1 newxito wrote: > No worries, this is a strictly limited edition, this thing is serial > number 1 of 1 :-) > I cheated a little bit; I just modified the original case and connected > the display part with a metal tube. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/034eb569-ea4b-49c1-ad2c-c6e81cc59c8fn%40googlegroups.com.
[neonixie-l] Re: Paging Lawrence Wilkins...
Rumours of Mr Wilkins' demise are, I am pleased to report, somewhat premature! Alive and well, and reporting in. Having some short term problems with my email address laurence.wilk...@dsl.pipex.com (ever since Pipex sold out to TalkTalk - downhill all the way :( ) Laurence On Saturday, 26 September 2020 at 19:42:55 UTC+1 Jon wrote: > Apologies Lawrence - the email address I have for you is bouncing. Are you > still active on here? I have a question about one of your (cool) clocks... > > Jon. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/7b6b0b9f-0821-41e6-8729-d306492b4b71n%40googlegroups.com.
[neonixie-l] Re: Cyclox II clock tube
It certainly is! :) Laurence Creator, Designer, Builder and Seller of around 250 CYCLOXes, worldwide. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/94b68c08-82ad-4140-a2a7-fed615de3001%40googlegroups.com.
Re: [neonixie-l] Re: Careful what you use to power your nixies...
The only thing you can safely assume with cheap goods from China, is that the seller is interested in your dollar, not your life. A not-foolproof test is simply to feel the weight of a charger body in your hand, when compared to a known, good (original equipment) specimin. The fake will often reveal themsleves by being lightweight - in every sense of the word. Unless you KNOW the provinance of the supply, assume any cheap Chinese charger is fake/dangerous. Do not believe ANY marking on them! The final acid test is to break them open and inspect them, although of course there is no going back from this! -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/0afba789-88bc-46e3-8050-e206e6149d63%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[neonixie-l] Re: IN-18 Tubes - Best place to get from?
Unless you've not turned the TV on for the last six months, you'll know that the Ukraine is in a state of some confusion, right now. The country is very split about its own future. This is MIGHT have an impact, somehere, on the chain of money/goods flowing from some parts of that country, to the West. I strongly recomend that you COMMUNICATE DIRECTLY with any supliers beforehand, to satisfy yourself that any transaction will not be impacted by the current sad events. As otherwise noted elsewhere, look for ebayers with solid feedback scores, and a history of selling this type of product; check past sales of IN18 nixie tubes in particular. Look for phrases like Date Matched and New, in box (NIB) or New Old Stock (NOS). *some *ebayers will sell you unmatched, randomly dated and well-used tubes, without pointing this out (which is naughty...) On Tuesday, 25 February 2014 15:16:45 UTC, Paul Parry wrote: Hi all, As someone quite new to Nixies, where would you recommend the best place to get some IN-18 tubes from? Direct from somewhere in Ukraine or off eBay? Cheers, Paul -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/46ff9d2e-01ea-4b9c-bec1-458d892a53cb%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: IN-18 Tubes - Best place to get from?
Well, Petro, I am truly glad to hear that! I really hope that things work out for the country On Tuesday, 25 February 2014 15:16:45 UTC, Paul Parry wrote: Hi all, As someone quite new to Nixies, where would you recommend the best place to get some IN-18 tubes from? Direct from somewhere in Ukraine or off eBay? Cheers, Paul -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/78e26376-2d26-4cb8-b9d0-73d9b9c5c275%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Math wizzards....
Bill, not unlike this one here, then! :) (my own design, of some five years back) http://www.youtube.com/watch?v=WgFVbnZrwYg I used a lookup table which the software consults at regular time intervals, once per display multiplex cycle, which was about every 6mS from memory. The table had about 170 entries in it for the full second. Once the table is done, there is no math in the software routine. It just looks up the value, and displays it. Incidently, you may find (as did I) that a swing of greater than about 60 degrees just doesn't look right. As you'll see, while I was at it, I made several other effects available to the user, all through lookup tables (no space efficient, but easier) Here is a simple sine wave spreadsheet. I've done it for steps of 5 degrees. You can change the number of LEDS in the swing in the yellow box - enjoy. Laurence On Saturday, 22 February 2014 15:31:04 UTC, Bill v wrote: Hello, I have built a clock controlled by a PIC with 6 numitrons in the centre. Around them is a circle of 60LEDs which are programmed to display a number of different patterns. I am currently working on a pendulum pattern which uses the lower 30 LEDs. I have the software done, the challenge is this: A pendulum has a period and an angular velocity that changes from 0 at the ends, and maximum in the center, following an equation. In the software I currently have 36 time slices (program steps, 0 to 35) in a half period of 107 clock cycles, for a total of 3852 cycles for one swing (left or right). Looking at one swing, my challenge now is to divide the 36 program steps of 107 clock cycles such that the total number of clock cycles remains 3852, but the actual number of clock cycles per step are divided such as to approximate the equation of one pendulum swing (left or right). Anyone willing to take a stab at this? Bill van Dijk -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/3e2253a3-117e-4157-83fb-5f6c1935%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. SINE table.xls Description: MS-Excel spreadsheet
[neonixie-l] Re: Found a drawerful of 7441s!
Yeah, be careful with those ones, David. They look like the lower voltage types. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/d4c243ea-e746-4cfe-af94-5895f46032c1%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Fascinating ebay sale ... apparently IN-18 production gear!
Lend me your bargepole - I wouldn't touch this deal with my own! This doesn't stack up. You are only going to need one piece of don't-know-how, and you would be completely stumped, I reckon. Of course, this item has appeared on eBay before (was it with the same seller?), and it didn't sell then. Why? Good luck to anyone buying it and shipping it half way around the world, only to find that DHL (stands for Dropped, High-kicked and Launched) or your international carrier of choice haven't just delivered you a pile of broken silica tubes. On Monday, 6 May 2013 11:23:54 UTC+1, Zedsquared wrote: This is interesting! http://www.ebay.co.uk/itm/261172534593 I've not got the cash or inclination to buy but would love to hear what people make of this, it's a great insight into what goes on in manufacture. Does anyone know what the green machine with flames does? What's in the cans? (I'd guess getter compound maybe ). Looking at the QA so far it implies that the digits have to be made with the supplied know how ... photo etching techniques and recipies perhaps? Cheers, Robin. P.S.I guess I should introduce myself :) Hi, I'm Robin from the UK, a software and hardware computer guy with a nascent ebay nixie acquisition habit but only a few breadboard rigs actually built yet. Here's hello world from my first PIC and nixie setup: https://www.youtube.com/watch?v=AqxDZUYhl2s Day job is RD at a company fitting out emergency service command and control vehicles with tech, weekend job is pyrotechnician with skyburst. I'm currently spending most of my time in bed with a laptop due to a broken ankle, bah! -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/aOqNfnjD0UgJ. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Nixie Pinball Display - Schematic feedback
Hello Zitt, first of all, this sounds like an interesting and worthwhile application for nixie tubes! You are to be congratulated on that. I am not saying your design wont work, but you've asked for comments, so here are mine... I do feel that you may have over complicated the LED drivers a little bit. Seems like an awful lot of semiconductors in there!. First of all, consider wiring pairs of LEDs in series, or even quads in series, depending on what (12V?) power supplies you have to hand. Then current limit them through a series resistor, and wire multiple strings of this arrangement in parallel and then back to just the one switching transistor. The resistors R56/R57 in your anode drivers are probably a bit low - you've got the best part of 2mA of (expensive) HT flowing down there. The driver transistor q21 etc. won't need that much base drive. I've used values three times yours before, without any issue or ghosting, etc. You are multiplexing this display on a one of six basis. That means each nixie tube is only going to see juice for maybe 15% of the time. Even if you overdrive them, they will be on the dimmer end of their possible light output, and I would imagine that for your application nice, bright displays are somethiung of a prerequisite. You might want to consider designing the mux to be two sets of one of three. As I say, it will work as you've got it, but you may be disappointed in the results. Check the pin-outs of the nixie tubes - i think you can save maybe one or two pins (you still need the PCB holes, of course, but now electrical connection to some pins). I think 190V HT may be a bit too hot. You may find the displays will work fine at 180V, even 170V. The tube's actual striking voltage is probably around 150V. You will need to set the anode current limiting resistors to suit, of course. That's the thing about electronics, isn't it? there are often many ways of doing it! Keep us up to date with your progress -- You received this message because you are subscribed to the Google Groups neonixie-l group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/FpmphJB6vA0J. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Help needed to design Swithmode step-up converter, this time not so Nixie-related
BARBEQUE?? That came out of my fingers as Because... On Tuesday, 27 November 2012 19:30:50 UTC, MrNixie (UK) wrote: Hmm, I think you need to give us a bit more info - your proposed circuit, supply voltage, etc. The mosfet and inductor won't complain much at 100C, but your LEDs might start to! And any electrolytic caps wont be winning any Long Service awards at those temperatures... Is the Mosfet running at this temp barbecue it is dissipating power, or is just in a hot place to begin with? Make sure you are indeed switching the Mosfet cleanly - check the Vgs curves in the spec sheet. Remember that at high frequencies, the gate of a mosfet just looks like a capacitor - you really have to DRIVE current in to it - are you relying solely on the output of the SMPS IC? Re series and parallel LED combinations - general rule of thumb is to arrange your LED load closest to the supply voltage, so that your SMPS is not having to step up or down too far from the supply rail, in either direction. You will see losses if you go for a very low voltage but high current output, or vice-versa My two milliamps' worth - -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/Ovq4QPwz_uEJ. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Art imitates life?
The artist is catherine.pal...@bt.com drop her a line if you like! Laurence On Mar 5, 11:55 pm, coggs bob.coggesh...@gmail.com wrote: Beautiful. Is there a direct face-on set of renderings ? Would love to use these and link to her site. On Mar 5, 4:11 pm, MrNixie (UK) laurence.wilk...@dsl.pipex.com wrote: Good evening all, a past customer of my nixie clocks has an active interest in detailed computer image rendering of objects that take her interest. Latest object to receive the treatment is the glorious IN18 nixie tube. Just think - even when the last IN18 is gone, we'll still have these... http://www.palmyria.co.uk/misc/miscobjects.htm#in18 NOT photos! Laurence -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Art imitates life?
Good evening all, a past customer of my nixie clocks has an active interest in detailed computer image rendering of objects that take her interest. Latest object to receive the treatment is the glorious IN18 nixie tube. Just think - even when the last IN18 is gone, we'll still have these... http://www.palmyria.co.uk/misc/miscobjects.htm#in18 NOT photos! Laurence -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Dallas/Maxim TCXO question
Well, as I said earlier, two separate batches of these chips were each remarkably close to one-another, and all a tad slow, as it happened. Uncallibrated, my batches might loose 30-60 seconds per year, IMO. I am sure the manufacturing process includes some sort of hardware/laser trimming operation, but beyond that the single ageing register is all you need. Yes, if you want to tune these, you'll need another even more accurate reference counter, and then measure the 32kHz or 1 Hz output. It does take some time ( several minutes) to calibrate the oscillator, as it doesn't react instantly to changes in the value stored in the ageing register (at least, not in my application. i think you can invoke an update now command, but I've not bothered). If your software is anything like my software (!!) and your application doesn't work, it will be because of an issue with your I2C data/clock streams. And on top of that, you need to execute a short sequence of commands to load or retrieve data. The DS3231 is probably no different to any other I2C device in this regard, but the sequence of data bits is really critical. Start off really simply trying to retrieve data and build from there. A digital (storage) 'scope is ideal for double checking the waveform. Everything else you need is in the extensive device spec sheet. And don't forget those two pesky I2C pullup resistors! (I did...) On Feb 23, 9:51 pm, Frank Bemelman bemel...@franktechniek.nl wrote: I had a quick look at the datasheet, and it seems there is no tuning register, only an aging register. That resister you can use if you really want to recalibrate it, using the DS3231 32Khz output and your 32Khz reference derived from a caesium clock or something. I wonder how Maxim calibrates these chips? A hidden register perhaps, in hidden e2prom? Cheers, Frank -Oorspronkelijk bericht- From: Cobra007 Sent: Thursday, February 23, 2012 10:14 PM To: neonixie-l Subject: [neonixie-l] Re: Dallas/Maxim TCXO question So, what is the best way to calibrate these chips? How do you figure out the values for tuning register and aging register? I normally set the tuning register by comparison with a second time source over 1 week, usually that is good enough for about 10 seconds per year. But how do you figure out the value of the aging register within 1 week (or quicker)? Michel -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/neonixie-l?hl=en-GB. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Dallas/Maxim TCXO question
Michel, no 100Hz output I am afraid, since the on board (embedded) crystal is 32.768KHz and of course 100Hz is not a sub multiple of this. 8.192KHz, 4.096KHz, 1.024KHz or 1Hz (which is what I use to interrupt the processor, and collect the latest time). The resolution of the on-chip ageing register is something like 3 seconds per bit per year. I set this as part of my nixie clock calibration. Interestingly, nearly all of the chips in my TWO most recent batches have needed almost the same ageing value! (-10 or 137, depending on whether you are counting up or down in the 8 bit register). If you are changing this register, it can take the chip up to a minute AND requires a change in temperature, before the oscillator will respond to the change, so you have to be patient. The DS3231 is only available in a 16 bit SO chip (SMD), but it is one of the easier SMD components to handle. The chip will run for a week on a 0.47F memory backup capacitor, too. Of course, the chip wont correct for DST. I do that in processor software, and write the new time back. So, if a DST change occurs while under battery power, your software needs to spot it and make the change, retrospectively, when main power is returned. The spec bangs on about incorporating a reset circuit, which I've never understood the need for. It looks to be a reset *OUTPUT* for other devices, rather than a DS3231 rest. Why? There is even an on-board temperature sensor. This is there primarily to apply the correct temperature compensation (it is the TC in TCXO!) to the crystal oscillator, but you can also read this register directly. However, in the case of a nixie clock, there are usually enough other watts floating about the board to raise this temperature a few variable degrees above ambient, so you cannot rely on this figure for room temperature - unless your application is REALLY low powered. Yes, a neat little chip, which rather renders other time references such as GPS or radio time codes unnecessary for all practical purposes. But then, I don't think of a nixie clock as just a practical time piece! Laurence On Feb 22, 10:46 pm, Cobra007 mic...@xiac.com wrote: Yes, you're right. Obviously I didn't know about this chip :-) It says there is an on-chip aging trim register. The DS3231 is in fact exactly the type of chip that I was after for my own clock! It has a programmable square wave output, need to check it out if I can get the frequency down to 100Hz, otherwise need external divider circuit. Michel On Feb 23, 1:04 am, Tidak Ada offl...@zeelandnet.nl wrote: Isn't it a TCXO is a Temperature Compensated X-tal Oscillator ? eric -Original Message- From: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] On Behalf Of Cobra007 Sent: woensdag 22 februari 2012 12:08 To: neonixie-l Subject: [neonixie-l] Re: Dallas/Maxim TCXO question Apart from temperature influences on the crystal, the frequency and stability also depend on what type of load capacitors you use. 1 second per day (99.999% accurate or 0.379Hz) is really not bad for an RTCC, a very fine tuned one uses a trimming capacitor and runs about 1 second per week. If you want to go more accurate than that, you will need to compensate for temperature and other influences. Michel On Feb 22, 4:02 pm, chuck richards chuc...@all2easy.net wrote: I have a few questions about the Dallas/Maxim 32KHZN/DIP TCXO ics: Has anyone out there in nixieland had much long-term experience with these? The reason I ask is because I've been using them now for about ten years and have noticed a few things about them. One thing I seem to notice is that they are not as accurate now as they were some years ago. I have one in a clock, and when new for the first few years it kept extremely accurate time. I kept well within 10 seconds per year then. More like +5 seconds in one year according to my old notes from actual running tests. It runs now about 20 to 30 seconds fast per year. Might that be due to crystal aging? And also, along the years I have gotten many batches of more free samples of these from Maxim. Some seem to be much more accurate than others. I just was testing one of them and it gains about one second in two days! I also ran across power rail noise affecting the accuracy of one of them in a clock I made. That problem was partially solved by putting a .1 uF ceramic disc cap. across the power input pins to it, and then putting 100 ohms in the +5 volt feed to it. In general, these do not seem as rock stable and accurate now as they once did. Any ideas what might be going on? Anyone else been using them? Thanks, Chuck $4.95/mo. National Dialup, Anti-Spam, Anti-Virus, 5mb personal web space. 5x faster dialup for only $9.95/mo. No contracts, No fees, No Kidding! Seehttp://www.All2Easy.netformoredetails! -- You received this message
[neonixie-l] Re: Dallas/Maxim TCXO question
Well, as a designer and manufacturer of nixie clocks which incorporate the fine Dallas 3231 Extremely Accurate on board TXCO RTC, I never have my own clocks running for more than a few weeks before I've pulled them to tinker with either the software or hardware! Instead I have to relay on reports from customers whose clocks drift by less than 5 seconds per year (once initially calibrated, which of course I do). Not sure about the longer term stability, though. There were lesser RTC devices, but I think the DS3231 tops the list for accuracy. Dallas used to run a real time demo site, showing how one of their development boards had run over several years, and I recall only gained 30 seconds in five years or so. Seems that site has gone, now? -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: hello from new guy
Brian, you might be tempted to run a couple of small NE2 colon bulbs in series, but you will probably find that their combined strike voltage is higher than your HT power supply - either straight away, or after a few months of bedding in. They just stop working! So, run the neons (each with their own series resistor) in parallel. These little NE2's are cheap, and prone to flicker. So buy a few spares, and run them in for a few days on your test bench at (say) 0.5mA each, and watch how they perform. Then select the best, stable ones. As John points out, only the cathode electrode will glow, so you might like to think about mounting/twisting the neon lamp so that the cathode faces forwards towards the viewer. Small point, but you'll see what I mean when you fire one up. Resistor values? Let's assume you've got 180V HT, and I'll go with John's maintain voltage of about 67V. So the resistor needs to drop the other 113V. Aim for about 0.5mA current initially, so according to Mr Ohm that's 226K, or 220K nearest E12 preferred value. That's your starting point, but don't be afraid to experiment with values between 47K (bright!) and 680K. The idea is to match the NE2 brightness in with your Nixies, so that the little fellas are not shouting look at me! all the time. I might also suggest... that you strap one NE2 and accompanying series resistor straight across your HT power supply, on the PCB, and close to the hot stuff. This will confirm and remind you whenever the HT is up and running, and just might prevent you sticking your finger where you shouldn't, just when you shouldn't! Listen to the voice of experience... :( And have fun :) On Dec 27, 11:54 pm, John Rehwinkel jreh...@mac.com wrote: Anyway, I'd like to use two neon lamps to display the colon between hours and minutes; do any of you have any suggestions for a lamp/tube that runs on a similar voltage as the nixies? Ordinary NE-2 bulbs seem to maintain at 67 volts or so, so a pair of 'em will generally run cheerfully from a nixie supply. You can also run them individually, with larger current limiting resistors. Running 'em on DC will only have one of the electrodes glow, which may or may not matter to you. There are various schemes to switch the power at a high frequency (so both electrodes appear lit) or a low frequency (so the colons dance at 1Hz or so). - Welcome aboard, John -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Old IN-18's !
You are making me blush :) Running partial fail IN18's at up to 15 mA for several hours will SOMETIMES resurrect or part restore them, but I have not yet found this to be a long term solution. YMMV of course. At least, during this process, you can read a book (possibly even get a TAN) from the light your straining IN18 gives off. Else selectively assign them to tens- seconds, tens-minutes and tens-seconds roles, of course. Happy new year to you all On Dec 25, 12:07 pm, Mefistofelix markpeters...@btinternet.com wrote: Merry Christmas Everyone ! I have 8 old IN-18's that have seen better days. When inserted into one of Mr Nixie(UK)'s excellent Cyclox 3 time pieces using it as a testbed, in daytime bright mode most of the cathodes light, but some have slight dark areas in the middle of the digits. When in night/dim mode this problem becomes more pronounced with only small lengths of some of the digts lighting up at all. Do you think this is 'cathode poisoning' (wot I have heard of) or just gradual deteriation caused by contamination of the gas ? Any ideas how to save them ? Maybe 6 hours in a low oven with the turkey ? - or should they be consigned to being connected to higher voltage to cause a festive bang and flash ? - If so what power do you suggest to make the most spectacular effect ?... (Please do not try this at home or at least when the wife is watching) M -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Internal cathode short-circuit?
Here's an even more exciting way of (sometimes!) reinvigorating a shorted tube. Chances are that a piece of debris or bent/moved wire has bridged two of the Cathodes. You should be able to find which two, by going around the base of the nixie tube, testing for any continuity (may be a short, or a few ohms) between each pair of wires - not just adjacent ones. This is best done with the device out of circuit if possible, or if in circuit with any ICs removed (you DID socket your ICs, didn't you? Of course you did...). DOUBLE CHECK that any continuity that you find is between cathodes and not a heater/getter or two common anode wires. Do this by comparing any shorts you find against the same wires of a good tube. Now get a power supply capable of delivering more than 24V at a couple of amps. Apply this briefly across the two shorted pins. With luck, this will blow the short circuit away, like a fuse going (you may even see a small flash). I have used this to good effect on a mix of nixie tubes (including IN18 and IN8's). LET ME REPEAT That this won't fix every case, and MAY make matters worse (blowing a cathode open circuit, if you are unlucky). But if the nixie tube is already otherwise unusable, what have you got to lose? Laurence WWW.MrNixie.com On Dec 18, 11:04 am, jb-electronics webmas...@jb-electronics.de wrote: Any idea how to fix this? Buy a few more tubes and replace the defective ones. Sometimes it helps to gently shake the tube. In some cases (not in yours, though) you could use the defective tube on a place in your application where it only needs to display the functioning digits. So say digits 5 and 7 are connected, but you only need digits 0,1,2 (i.e. the tens of hours in a clock). Jens -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: MC34063 component choice for +475V @ 50mA output, help needed!
Jeepers, Buddy! 475V at 50mA? Did you check your life insurance? Not popular for supplies in the few-watts range, but if you need this sort of power maybe a valve amp transformer is going to be your better bet? -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: 555 based HV supply question
No doubt these 555 power supplies can work, but the efficiency can be poor, and there is no current overload protection. If you can live with the extra wasted power (means a heat sink, for your numbers) and can trust yourself never to short the power supply out, then these circuits will deliver. But you will never beat a custom SMPS IC with a generic 30 year old one IMHO. On Nov 21, 5:50 pm, chuck richards chuc...@all2easy.net wrote: All of the recent discussion about the little boost converter HV supply is getting me interested in trying the idea. I looked around on the web and came across a few schematics for it. It uses a 555 timer ic as the controller, and I see that various frequencies are used. Looks like rounding up the FET, the diode, and the inductor would be no big deal. But, are these things really any good? Will one of them hold decent regulation when running (6) nixies? My estimated total current at 170 volts DC would be about 2.2 mA per tube. That would be about 13.2 mA total. Is it worth experimenting with? I ask, because it seems quite tough to beat John Taylor's model 1363 and 1364 power supplies. I have one of his 1364 supplies here, and it's really slick! Thanks. Chuck Richards $4.95/mo. National Dialup, Anti-Spam, Anti-Virus, 5mb personal web space. 5x faster dialup for only $9.95/mo. No contracts, No fees, No Kidding! Seehttp://www.All2Easy.netfor more details! -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Mostek MK50250N chip and using it for nixie or VFD clocks.
Hello, That chip uses upside down (i.e negative 12V) supply, so you have to keep your wits about you! I suggest that it is a non-starter for nixie conventional tubes, as its output is designed for a seven segment display. At a push, you might be able to design something to drive seven segment VFDs. But the chip output currents are low - you will need buffer chips to drive the VFD voltages. The recommended 74591/74592 driver chips still look to be available - why not build a retro LED clock, to the reference design? But for Nixie/VFD's? Hmm. Unless you have a passion for this chip, I wouldn't start from here I guess you have this - http://www.datasheetarchive.com/MK50250N-datasheet.html Laurence On Oct 22, 2:23 am, neutron spin mrstan...@charter.net wrote: Hello, Has anyone had any luck using the MK50250N chip? What about the driver circuitry used ?...Thanks.. Robert W8UUU -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Disposable camera as power supply
...erm, not sure what you are referring to, there. Inductors are rated for their inductance (obviously!), and their peak current before saturation (also their DC resistance, Q factor, resonant frequency, etc., but those criteria will be less important in most smal SMPS power supply designs, as long as the inductance and current capacity are right). I have not seen an inductor rated in Watts before! VERY rough calcs - Assume you want 180V out at 15 mA, that's 2.7W output power You'll be doing well if the design returns 80% efficiency, so that's 3.4 W input power Assume a 12V primary supply, so that's an AVERAGE draw of 300mA (I keep rounding the numbers) If the duty cycle of the driving transistor is 50%, (and the current is a linear ramp), then the PEAK current will be FOUR TIMES the average, so over 1Amp peak. If your chosen inductor can't handle that current, it will saturate; the circuit efficiency will drop and the inductor will get HOT. On Oct 11, 1:51 pm, Imbanon imba.a...@gmail.com wrote: Many thanks for that explenation, I did not know how to read these. I got my hands on a 100uH inductor of 0.5W for the circuit I posted. Is that enough or should I get one with bigger wattage? Thanks On Oct 9, 8:17 pm, MrNixie (UK) laurence.wilk...@dsl.pipex.com wrote: That little simple 555 circuit is fairly standard and basic, and will work. It wont give top performance, but who cares? Stick closely to the advised components, particularity for the main FET, switching diode (NOT a IN4007 clone!) and inductor. Keep the layout reasonably compact. DON'T touch the metal tab of the FET when it is running! I like the warning: enough energy to potential(LY?) kill a person should they be connected between the high voltage output and ground in the right way, so be careful when working on this circuit! I think they meant - if connected in the WRONG way! But the warning stands. The Inductor in the other ready-made circuit I mentioned carries the number 221. This is the same as resistor coding, and in this case is the value in MicroHenries - 2, 2 and one zero; so 220uH. Anything in the range 100uH - 330uH will kinda work in these circuits, but needs to be able to handle the peak current, without saturating. On Oct 9, 6:22 pm, daddyvan2005 daddyvan2...@yahoo.com wrote: I bought one of these in the link above and like it. If Lance still sells them. I use it for bench testing/proto work. It#39;s adjustable which makes it nice for certain apps. John Taylorwww.tayloredge.comhasareal nice module that#39;s pretty much plug and play and works real well also adjustable. Koswww.kosbo.comalsosellsone. In all I found that having one for the bench was required because once you start playing with neon your hooked. Plus you should be checking those nixies before installing them the be sure they actually work. From: Imbanon lt;imba.a...@gmail.comgt; To: neonixie-l lt;neonixie-l@googlegroups.comgt; Sent: Sunday, October 9, 2011 10:08 AM Subject: [neonixie-l] Re: Disposable camera as power supply Thanks for your reply guys! And so I have gave up on my current supply, and decided to make my own. I didn#39;t want to make my own as I thought that it will be the most expensive option, but I was wrong. Seems like all these pre-made supplys are around 20 bucks, a bit less, and for that kind of money I can make 5 of thesehttp://www.ledsales.com.au/kits/nixie_supply.pdf,andstillhave a lot of spare parts! Does anyone have any experience with these? Are they alright? Thanks again! On Oct 9, 6:25 pm, quot;MrNixie (UK)quot; lt;laurence.wilk...@dsl.pipex.comgt; wrote: gt; A couple of points. gt; gt; You are going to need more than 0.2-0.3 mA to fully light a nixie gt; tube. Otherwise, you will see gaps in the numerals. gt; gt; A camera flash power supply has DREADFUL efficiency, is usually gt; designed to work from a 1.5V battery, and does so by pulling HUGE gt; currents - often over 1 amp. Here are the reasons why. gt; gt; Assume you need a 200V power supply, and at about 6 mA. That#39;s 1.2W gt; out. The simple circuit found in cameras will be no better than 50% gt; efficient, so that#39;s at least 2W in. Even with a fully charged gt; battery, that#39;s 2/1.5 OVER ONE AMP in!! so you#39;ve got to build a power gt; supply capable of delivering over an amp, at one and a half volts, gt; just to pamper to your camera circuit. Why bother? gt; gt; John points out several alternatives; I would further add that I have gt; seen small custom-built power supply modules on eBay that will run gt; from a much more convenient 12V or thereabouts, and return much better gt; efficiencies. If you are wary of building your own, then certainly gt; look at one of these: gt; gt;http://www.ebay.co.uk/itm
[neonixie-l] Re: Disposable camera as power supply
A couple of points. You are going to need more than 0.2-0.3 mA to fully light a nixie tube. Otherwise, you will see gaps in the numerals. A camera flash power supply has DREADFUL efficiency, is usually designed to work from a 1.5V battery, and does so by pulling HUGE currents - often over 1 amp. Here are the reasons why. Assume you need a 200V power supply, and at about 6 mA. That's 1.2W out. The simple circuit found in cameras will be no better than 50% efficient, so that's at least 2W in. Even with a fully charged battery, that's 2/1.5 OVER ONE AMP in!! so you've got to build a power supply capable of delivering over an amp, at one and a half volts, just to pamper to your camera circuit. Why bother? John points out several alternatives; I would further add that I have seen small custom-built power supply modules on eBay that will run from a much more convenient 12V or thereabouts, and return much better efficiencies. If you are wary of building your own, then certainly look at one of these: http://www.ebay.co.uk/itm/NIXIE-TUBE-POWER-SUPPLY-MODULE-CLOCK-2-OUTPUTS-/250871015688?pt=UK_Consumer_VintageAudio_RLhash=item3a6913e908 ALSO! A camera flash power supply will be designed to charge a much larger capacitor (for the flash) than these custom supplies like the ones above, and this is capable of giving you a much bigger BELT when you put yourself across that open circuit 330V, than a smaller, current limited 180V supply. And, no matter how careful you are, sooner or later you will do this! Alas, I know this... :( Laurence (AKA MrNixie, UK) On Oct 9, 3:08 am, John Rehwinkel jreh...@mac.com wrote: I've just got my IN-14 tubes and started experimenting on my first nixie project - the clock, of course! For now I am using a disposable camera as my power supply. Shorted out with an amp meter, it gives a steady 12.8mA at 330V, which is better than expected. More accurately, it pushes 12.8mA through a short at zero volts. I'm guessing the 330V is no load. So in-between, you're getting less than 330 volts at less than 12.8mA. So my question is; should I continue bothering with this power supply (should it even be used for 6 tubes) and try to fix my schematics, or just make my own power supply which I am not so fond of. I'm guessing the camera supply just isn't up to the job, sad to say, but likely. So there are a few ways you could proceed. If there are more where that came from, you could use six camera supplies, one for each tube. That might work, and would be amusing. Otherwise, you'd have to come up with the voltage some other way. The easiest way is probably to buy a ready-made supply like the Tayloredge ones. They're small, reliable, and very cost effective at $13 apiece, and you don't have to make your own. Alternatively, if you're using an AC supply, you can use a transformer in reverse to step-up the voltage, and rectify that. Three parts (transformer, diode, and capacitor) and you're there (you can steal the capacitor and probably the diode from the camera supply). Can driving nixies at such low voltage and current damage my nixies? Yes, running them underdriven like that can lead to cathode poisoning. It can be reversed, but it's disappointing when it happens. - John KG4L -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Disposable camera as power supply
That little simple 555 circuit is fairly standard and basic, and will work. It wont give top performance, but who cares? Stick closely to the advised components, particularity for the main FET, switching diode (NOT a IN4007 clone!) and inductor. Keep the layout reasonably compact. DON'T touch the metal tab of the FET when it is running! I like the warning: enough energy to potential(LY?) kill a person should they be connected between the high voltage output and ground in the right way, so be careful when working on this circuit! I think they meant - if connected in the WRONG way! But the warning stands. The Inductor in the other ready-made circuit I mentioned carries the number 221. This is the same as resistor coding, and in this case is the value in MicroHenries - 2, 2 and one zero; so 220uH. Anything in the range 100uH - 330uH will kinda work in these circuits, but needs to be able to handle the peak current, without saturating. On Oct 9, 6:22 pm, daddyvan2005 daddyvan2...@yahoo.com wrote: I bought one of these in the link above and like it. If Lance still sells them. I use it for bench testing/proto work. It#39;s adjustable which makes it nice for certain apps. John Taylorwww.tayloredge.comhas a real nice module that#39;s pretty much plug and play and works real well also adjustable. Koswww.kosbo.comalso sells one. In all I found that having one for the bench was required because once you start playing with neon your hooked. Plus you should be checking those nixies before installing them the be sure they actually work. From: Imbanon lt;imba.a...@gmail.comgt; To: neonixie-l lt;neonixie-l@googlegroups.comgt; Sent: Sunday, October 9, 2011 10:08 AM Subject: [neonixie-l] Re: Disposable camera as power supply Thanks for your reply guys! And so I have gave up on my current supply, and decided to make my own. I didn#39;t want to make my own as I thought that it will be the most expensive option, but I was wrong. Seems like all these pre-made supplys are around 20 bucks, a bit less, and for that kind of money I can make 5 of thesehttp://www.ledsales.com.au/kits/nixie_supply.pdf,and still have a lot of spare parts! Does anyone have any experience with these? Are they alright? Thanks again! On Oct 9, 6:25 pm, quot;MrNixie (UK)quot; lt;laurence.wilk...@dsl.pipex.comgt; wrote: gt; A couple of points. gt; gt; You are going to need more than 0.2-0.3 mA to fully light a nixie gt; tube. Otherwise, you will see gaps in the numerals. gt; gt; A camera flash power supply has DREADFUL efficiency, is usually gt; designed to work from a 1.5V battery, and does so by pulling HUGE gt; currents - often over 1 amp. Here are the reasons why. gt; gt; Assume you need a 200V power supply, and at about 6 mA. That#39;s 1.2W gt; out. The simple circuit found in cameras will be no better than 50% gt; efficient, so that#39;s at least 2W in. Even with a fully charged gt; battery, that#39;s 2/1.5 OVER ONE AMP in!! so you#39;ve got to build a power gt; supply capable of delivering over an amp, at one and a half volts, gt; just to pamper to your camera circuit. Why bother? gt; gt; John points out several alternatives; I would further add that I have gt; seen small custom-built power supply modules on eBay that will run gt; from a much more convenient 12V or thereabouts, and return much better gt; efficiencies. If you are wary of building your own, then certainly gt; look at one of these: gt; gt;http://www.ebay.co.uk/itm/NIXIE-TUBE-POWER-SUPPLY-MODULE-CLOCK-2-OUTP... gt; gt; ALSO! A camera flash power supply will be designed to charge a much gt; larger capacitor (for the flash) than these custom supplies like the gt; ones above, and this is capable of giving you a much bigger BELT when gt; you put yourself across that open circuit 330V, than a smaller, gt; current limited 180V supply. And, no matter how careful you are, gt; sooner or later you will do this! Alas, I know this... :( gt; gt; Laurence (AKA MrNixie, UK) gt; gt; On Oct 9, 3:08 am, John Rehwinkel lt;jreh...@mac.comgt; wrote: gt; gt; gt; gt; gt; gt; gt; gt; gt; gt; I#39;ve just got my IN-14 tubes and started experimenting on my first gt; gt; gt; nixie project - the clock, of course! For now I am using a disposable gt; gt; gt; camera as my power supply. Shorted out with an amp meter, it gives a gt; gt; gt; steady 12.8mA at 330V, which is better than expected. gt; gt; gt; More accurately, it pushes 12.8mA through a short at zero volts. I#39;m guessing gt; gt; the 330V is no load. So in-between, you#39;re getting less than 330 volts at less gt; gt; than 12.8mA. gt; gt; gt; gt; So my question is; should I continue bothering with this power supply gt; gt; gt; (should it even be used for 6 tubes) and try to fix my schematics, or gt; gt; gt; just make my own power supply which I am not so fond of. gt; gt; gt; I#39;m guessing the camera
[neonixie-l] Re: Large VFD 7 x 9 dot matrix displays not as they seem???
Thanks to everyone for their replies. Speaking as someone who DOES know a thing or two about driving multiplexed nixie and VFD displays (several hundred such clocks sold), I can now confirm that, if these items are not exactly duds, they are NOT capable of being driven in a 7x9 addressable display format. Grids 1 and 9 are internally SHORTED TOGETHER via a cross bar, which looks like it was intended to help in the construction and alignment of the display, with a view to being broken off before the glass seal was complete. Also, grids 2 to 8 are simply NOT CONNECTED internally! You wouldn't really be able to pick this out from the ebay photos, but it is plain to see with a display in your hand, and with an eyeglass. The eBay listing is therefore incorrect when it states connectivity to some grids. I have no strong opinion or even interest as to their origin, but they are date stamped in Russian with an April 1998 date. I suggest you avoid, while I attempt to communicate with the seller. Laurence On Jul 19, 7:12 am, marcin marcin.r.adam...@gmail.com wrote: If the pinout of the tubes is not as in the auction description and the seller fails to answer your email start the 'Resolve a problem' with ebay. It should prompt the seller to take notice. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Large VFD 7 x 9 dot matrix displays not as they seem???
That's the next option. On VERY close inspection, I can now see that not all of the leads into the device are connected! :( On Jul 18, 8:54 pm, Nicholas Stock nickst...@gmail.com wrote: I've looked at these on eBay a few times and often considered buying a few for experimentation6 of them would make a really cool word clock...shame to hear that they might be defective...can you return them (I know it's a hassle..). Nick On Mon, Jul 18, 2011 at 12:44 PM, MrNixie (UK) laurence.wilk...@dsl.pipex.com wrote: Hmm - I might have just made an expensive mistake (or just be unlucky so far). Has anyone bought any of the exquisite-looking huge 7 x 9 dot matrix display off ebay? I can't get them to run correctly. On closer inspection, they strike me as mis-manufactured items, all with the same bizarre fault (problem with the assembly machine?) Several of the grids do not appear to be connected to the external pins. Those grids which are connected appear to be shorted together. Under a lens, this is clear to see. Anyone else had any experience? Laurence -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: PicKit 3
Hello, what about this from the UK? http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItemitem=150464234759 Or even this one from China. Half the price, twice the risk! Take your pick (PIC?) http://cgi.ebay.co.uk/Clone-Microchip-Development-Programmer-Mini-PICKIT-3-/370526894163?_trksid=p4340.m263_trkparms=algo%3DSIC%26its%3DI%252BC%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D15%26pmod%3D150464234759%26ps%3D63%26clkid%3D1415835694672055006 Actually, I've bought stuff from Sure Electronics before, and had no problem. Microchip have made the PIC Kit open source, so other companies can (and do) easily copy it. I guess Microchip aren't bothered - the only reason you'd by a clone programmer is to program more genuine Microchips... Regards Laurence On Jul 17, 8:06 am, jb-electronics webmas...@jb-electronics.de wrote: Hi folks, I need your help: I finally convinced myself of getting a PicKit 3 from MicroChip. They have it readily available in the US, but not here in Europe, I would have to wait till September. Is there someone willing to purchase the PicKit 3 as well as the hookup cable (AC164110) http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGEnodeI...http://www.microchipdirect.com/productsearch.aspx?Keywords=AC164110 for me and then send it to Germany? I can pay in advance via PayPal. I would be very glad if someone from the states could help me. Best regards, thanks in advance, Jens -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Keeping your clock accurate
See how active this thread is, and how many options you have! My two cents (sorry - pence) Longer term (days, weeks), a mains referenced clock will be your best bet - your utility suppliers see to that in the longer term, for the benefit of the many MILLIONS of legacy mechancial devices that use the AC mains as their only reference. However, such a clock will gain and loose a few seconds throughout different times of the day, when the grid slows down a little under heavey load (think car going up hill), then speeds up again to make good the lost time during the night and late mornings. If you want good absoute time, all the time, even with the actual of day time itself, then GPS or WWVB/MSF time code receivers are the way to go. But beware - radio signals can be unreliable, you will still need a way of maintaining time locally in the event that your external source fails for some reason. Also, you are looking at more cost, more wires, more software. Simple Crystal oscillators that are designed just to clock your CPU can be PANTS (quaint English expression meaning not particulay good). They will let you down in three ways; absolute frequency, long term drift and Temperature. Sure, some clever software can correct for absolute frequency errors once you know what the error is, but no simple solutions that I have seen will accomodate temperature drift, which can be significant. Which brings us to Temperature Controlled Crystal Oscillators (TXCO). These can be bought now as IC's that run cold (no heating requirements). The on-board precision crystal is already laser tuned to be pretty damn near spot on (and is also still controllable in absolute terms using internal software settings), AND an onboard temperature sensor adjusts the capacitance across the crystal to compensate for temp changes. Check out the DS3231 from Maxim. It is only available as an SMD part, I beleive, but I have hand soldered these without issue. This little device is quite capable of offering better than 15 seconds a year accuracy - more if you have the time to fine tune it in the first place. Maxim call it Extremely Accurate, which for a general clock, it is. It leaves similar simpler crystal controlled RTCs in the dust for accuracy. And you get battery backup, of course. I have built clocks around ALL of the above options. They all work, within the limits mentioned. My favourite is now the DS3231. For all practical purposes (of mine), it makes the GPS or WWVB route somewhat redundant. That was probably THREE cents' worth :) On Jun 2, 3:39 am, threeneurons threeneur...@yahoo.com wrote: in the US, line frequencies are its adjusted whenever it hits 20s/10s of error. :http://en.wikipedia.org/wiki/Utility_frequency. - Robert I've used line frequency for decades, and I only touch those clocks twice a year. And usually that's only to adjust the hour (Daylight Saving). Rarely touch the minutes button. The correction scheme described on Wiki should be satisfactory for long term accuracy. Short term, who cares. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Keeping your clock accurate
CORRECTION! TXCO stands for Temperature COMPENSATED Crystal Oscillator - NOT Temperature CONTROLLED one. The chip uses no power to control the temperature, it merely compensates the crystal capacitors to ALLOW for it. Must read own notes before hitting send - sorry. On Jun 2, 10:01 am, MrNixie (UK) laurence.wilk...@dsl.pipex.com wrote: See how active this thread is, and how many options you have! My two cents (sorry - pence) Longer term (days, weeks), a mains referenced clock will be your best bet - your utility suppliers see to that in the longer term, for the benefit of the many MILLIONS of legacy mechancial devices that use the AC mains as their only reference. However, such a clock will gain and loose a few seconds throughout different times of the day, when the grid slows down a little under heavey load (think car going up hill), then speeds up again to make good the lost time during the night and late mornings. If you want good absoute time, all the time, even with the actual of day time itself, then GPS or WWVB/MSF time code receivers are the way to go. But beware - radio signals can be unreliable, you will still need a way of maintaining time locally in the event that your external source fails for some reason. Also, you are looking at more cost, more wires, more software. Simple Crystal oscillators that are designed just to clock your CPU can be PANTS (quaint English expression meaning not particulay good). They will let you down in three ways; absolute frequency, long term drift and Temperature. Sure, some clever software can correct for absolute frequency errors once you know what the error is, but no simple solutions that I have seen will accomodate temperature drift, which can be significant. Which brings us to Temperature Controlled Crystal Oscillators (TXCO). These can be bought now as IC's that run cold (no heating requirements). The on-board precision crystal is already laser tuned to be pretty damn near spot on (and is also still controllable in absolute terms using internal software settings), AND an onboard temperature sensor adjusts the capacitance across the crystal to compensate for temp changes. Check out the DS3231 from Maxim. It is only available as an SMD part, I beleive, but I have hand soldered these without issue. This little device is quite capable of offering better than 15 seconds a year accuracy - more if you have the time to fine tune it in the first place. Maxim call it Extremely Accurate, which for a general clock, it is. It leaves similar simpler crystal controlled RTCs in the dust for accuracy. And you get battery backup, of course. I have built clocks around ALL of the above options. They all work, within the limits mentioned. My favourite is now the DS3231. For all practical purposes (of mine), it makes the GPS or WWVB route somewhat redundant. That was probably THREE cents' worth :) On Jun 2, 3:39 am, threeneurons threeneur...@yahoo.com wrote: in the US, line frequencies are its adjusted whenever it hits 20s/10s of error. :http://en.wikipedia.org/wiki/Utility_frequency. - Robert I've used line frequency for decades, and I only touch those clocks twice a year. And usually that's only to adjust the hour (Daylight Saving). Rarely touch the minutes button. The correction scheme described on Wiki should be satisfactory for long term accuracy. Short term, who cares. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Appropriate duty cycle for IN-12s and similar Nixies?
Robert, I forecast a lively discussion, here! Many people will have their own views. David Forbes' comment about life expectancy being a function of the CUBE of the current is new to me, but I have no reason to doubt it. I get the feel that driving the tube 1:6 is just too much, but that 1:3 or 1:2 works OK. I have built all types. My own anecdotal findings are that steadily driven display are brighter than multiplexed display **even for the same average current** Mulitplexing does open up the possibilty for display dimming and fading. It also opens up the possibility for flicker, and the dreaded singing tubes! Thing is - just try it. But you probably wont notice any impact on life expectancy for many years... LW On Jun 1, 8:13 pm, Robert Sexton rob...@kudra.com wrote: Hello all, I'm working on some Nixie-driving circuitry, and I noticed in one of my data sheets that they called out a spec for filament duty cycle. There seem to be plenty of multiplexed designs out there, too, so the tubes obviously work when not continuously driven. Does anybody have suggestions on what power input is appropriate for a good appearance? I'm sure there are implications for tube life in there as well. I can build a drive system based upon either discrete or multiplexed drivers, and I'm wondering if there are non-obvious tradoffs here. - Robert -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Supertex HV7022
I spoke to a technical guy at Supertex in the UK a few months back. He said that they were working on a 5V version, though I haven't seen or heard any further. There are other reports that these devices will actually run fine from 5V, rather than 12V, logic levels, though I haven't tried this myself. Might be worth experimenting. I have used HV9308's which are designed for 5V logic inputs, but only switch 80-90V tops, so you have to be careful. That's OK if you've got (say) 180V supply, then there will never be less than 120V dropped through the nixie, leaving the HV9308 just to switch the last 60V or so to ground. It works. Two of these 32 bitters in cascade drive six nixies unmultiplexed, but because I also like to transition/fade the display, required quite a bit of work to optimise the software to get the refresh rate I needed. It basically means shuffling out alternating patterns of 64 bits, 200 times a second! Power consumption of the HV9308s is not a problem at all - less than 10 mA from Vcc. *** On May 29, 1:16 am, Robert Sexton rob...@kudra.com wrote: A reall hungry device might consume 30mA @ 1.8v. My biggest problem with the supertex device is the strange logic levels. It looks like the economics is a wash. The lower chip count is an improvement, but you'll also need to add a 12v rail to your device for level shifting. That may undo the simplicity advantages of the supertex solution -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Supertex HV7022
Just one other thing - if anyone DOES try running these current generation Supertex chips at 5V rather than 12V, it is very likely that they will only do so at a somewhat lower clock speed. Don't expect to pump 8MHz into them at these low voltages! LW On May 29, 10:13 pm, kosbo.com k...@kosbo.com wrote: How busy we are! it takes over 2 months to get first reply on my post... ;-) CPLD is good and for sure you can make bits registers there easily, but I have not seen any CPLD , which could manage 250v outputs and up to 1.5A total ground current ... I have got a few HV7022 samples and making prototype now, where I hope to use just chip outputs to control both nixie tubes anodes and cathodes. I hope I can control it with just standard TTL 5V levels, as absolute supply maximum voltage range for Vdd is -0.3 to +15V, so 5v is good enough within this range... I'll let you know first test results within a few days... Best regards, Konstantinwww.kosbo.com On 27 May, 07:22, Robert Sexton rob...@kudra.com wrote: Thats an interesting device, but it looks like it wants 12V control logic. You can build a 60-bit shift register from a CPLD for about $3. -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Ghosting on IN-14s even with long blanking period.
Hmm, so i ain't so smart at uploading images! try again... https://docs.google.com/leaf?id=0B3KTZNOahiFEZGY5NGJmMWUtNDE5Mi00NTgzLWI1NWQtMmMxZDQ3MTg3ZmUysort=namelayout=listnum=50 (but basically, it is a very similar idea to David Forbes Anode drivers). LW On Feb 6, 5:39 pm, will ossumguyw...@gmail.com wrote: Also, as for current leakage, remember that my DMM literally shows like 6mV from anode to ground when the anode is off, but then for some reason whenever the 7 on the other tube lights up, the anode voltage shoots up, and the same thing happens to a smaller extent with the decimal points. On Feb 6, 11:15 am, will ossumguyw...@gmail.com wrote: Hey MrNixie, I can't seem to access your link. And indeed, now is a time when I find myself wishing for a good scope. I'm trying to contact a guy on craigslist right now for one. I was able to switch my MOSFET pretty well with a totem-pole assembly (two 100 ohm resistors connected to PNP and NPN transistors, both joined at the emitters and connected directly to the gate of the MOSFET). So yes, two resistors and two transistors, but I've already gone and used them. BTW, I'm actually using an IRF730 in my circuit, I saved the IRF740 in case I needed to switch a bigger load. On Feb 6, 5:40 am, MrNixie (UK) laurence.wilk...@dsl.pipex.com wrote: Will, This is the point (in case you hadn't noticed!) when a 'scope comes in real handy! You really want to pursue that - I use mine a lot for fault finding my designs! It will pay for itself in your time, Teach you loads and reduce frustrations. I think your issue is not an AC (i.e. transistors not switching off in time) issue, but a DC (leakage currents) one. I might suggest a different arrangement for your anode drivers, tho. This is my own tried and tested arrangement: https://docs.google.com/leaf?id=0B3KTZNOahiFEZGY5NGJmMWUtNDE5Mi00NTgz... (i hope you can see that?) Also, I can save you at least two resistors and two transistors in your HT power supply. Junk that crappy old chestnut of a FET IRF740 (pah!) and get a decent low Vgs one from the likes of Toshiba 2SK3562, to name but one. These switch cleanly with a gate voltage of 5V, supplied STRAIGHT from your controller IC. Laurence -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
[neonixie-l] Re: Ghosting on IN-14s even with long blanking period.
Will, This is the point (in case you hadn't noticed!) when a 'scope comes in real handy! You really want to pursue that - I use mine a lot for fault finding my designs! It will pay for itself in your time, Teach you loads and reduce frustrations. I think your issue is not an AC (i.e. transistors not switching off in time) issue, but a DC (leakage currents) one. I might suggest a different arrangement for your anode drivers, tho. This is my own tried and tested arrangement: https://docs.google.com/leaf?id=0B3KTZNOahiFEZGY5NGJmMWUtNDE5Mi00NTgzLWI1NWQtMmMxZDQ3MTg3ZmUysort=namelayout=listnum=50 (i hope you can see that?) Also, I can save you at least two resistors and two transistors in your HT power supply. Junk that crappy old chestnut of a FET IRF740 (pah!) and get a decent low Vgs one from the likes of Toshiba 2SK3562, to name but one. These switch cleanly with a gate voltage of 5V, supplied STRAIGHT from your controller IC. Laurence -- You received this message because you are subscribed to the Google Groups neonixie-l group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
