[neonixie-l] Re: IV-15 / DM-160 -- Wire-up help needed
Fortunately they aren't much more complicated to drive. The DM-160 includes sample circuits and seems to be available here: https://frank.pocnet.net/sheets/009/d/DM160.pdf It needs 1V across the filament, +50V or so on the anode (referenced to the filament as it's a directly heated cathode.) and 0V connected to the grid via a 100K resistor. Note that the datasheet shows that the filament is driven with an AC voltage. This avoids having a DC voltage gradient across the filament relative to the grid and anode that would possibly cause it to light unevenly. It should work with DC and the filmanent should have been laid suitably (I.e. a single filament going up and back down the tube) such that it does light fairly evenly but you will need to consider that one end of the cathode will have a different voltage relative to the grid and this will affect the grid cutoff voltage. To just make it glow you can hook up* -f to 0V *and* +f to 1V.* The average voltage of the cathode is then 0.5V so you could hook the *g* *to 1V via a 1 Megohm resistor* (based on the example in fig.2 which shows how the grid can be slightly positive biased as long as the current is appropriately limited). Then hook the anode *a to +50V*. On Friday, January 5, 2024 at 7:02:04 AM UTC+10 HikariFaith wrote: > So I have a bunch of IV-15 / DM-160 VFD tubes I got a few months back (I > have a mix of both) and have been wanting to experiment with them a bit. > The problem is they're not as straightforward as the nixies I've been > working with, so I don't understand how to identify the individual > wires/pins on them, nor have the datasheets been helpful in knowing how to > turn them on or what voltage they need to turn on. Can I please get an > explanation of how to wire up these tubes? I really want to see how they > look in person. -- 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/6868ee74-25b0-4158-ae4c-5b9a897b4a0an%40googlegroups.com.
Re: [neonixie-l] Scope Clock SC200C
Given how far you have gone I'd lift pin 2 of U17 (leaving it unconnected) and measure the grid voltage. Then connect PIn 2 of U17 to POS5D and measure it again. The voltage should be more positive with the pin connected to POS5D. That would answer one and for all if the grid control is functional. It would also help to know which CRT model you have. On Thursday, October 28, 2021 at 12:39:19 PM UTC+10 GEK wrote: > I'm getting approximately: > Astig +124v > Focus/A2 -852v > Cathode/Bright-1210v > Grid -1262v > > The manual suggests that the Brightness has about -1300v, focus about > -900v and Astig +300v > I can adjust the Astig from 0 - 240 but the image is sharpest at 124v. > > - Gary > > On Wednesday, October 27, 2021 at 10:48:16 AM UTC-4 GEK wrote: > >> I probably do have a 10meg resistor down in my cellar, time to dig. I >> wasn't sure if I'd need to create an actual voltage divider with 2 >> resistors/ground wire so that's helpful. I'd hate to destroy a Fluke... >> >> On Wednesday, October 27, 2021 at 1:06:19 AM UTC-4 gregebert wrote: >> >>> Most DMMs have 10Meg input impedance, so you can put a 10meg resistor >>> in-series with your meter, and measure double the voltage. It wont be >>> exact, but pretty close. If you really need an exact measurement, then >>> measure a stable lower voltage without the resistor, then again with it. >>> Dividing those 2 measurements will give you a ratio close to 2.0, and you >>> can use that when measuring your high voltage. >>> >>> >>> On Tuesday, October 26, 2021 at 8:40:54 PM UTC-7 GEK wrote: >>> >>>> Thanks everyone for the hints, I'll look more closely at the HV - I'm a >>>> bit shy about measuring as I don't have a meter that will go to -1300v for >>>> the bright. >>>> >>>> - Gary >>>> >>>> On Tuesday, October 26, 2021 at 3:17:49 PM UTC-4 Bartek Ogryz wrote: >>>> >>>>> I'm not familiar with that project and that circuit, but based on my >>>>> experience in CRT TV repairs, if you have a proper blanking signal, >>>>> something must be wrong with HV as Tristan said. >>>>> Grid1 - negative voltage on this grid allows electrons to flow >>>>> (brighter picture), 0V blocks them (darkness). This grid can be driven by >>>>> the blanking signal, >>>>> Grid2 - is the screen grid, high voltage accelerates the electrons and >>>>> brightens the screen. If that voltage is too high, it can "force" >>>>> electrons >>>>> to flow, regardless of the Grid1 voltage. >>>>> Chceck the main power supply first - if it's voltage is too high, all >>>>> HV voltages will also be too high. >>>>> wtorek, 26 października 2021 o 05:02:21 UTC+2 Tristan napisał(a): >>>>> >>>>>> The brightness pot needing to be turned right up still suggests that >>>>>> you have a problem with grid voltage control. I'd expect to see some >>>>>> higher >>>>>> frequencies much higher than 60Hz on the BLNK- signal as well though. >>>>>> I'd >>>>>> be surprised if the problem was in the supply sections for the cathode >>>>>> or >>>>>> anode given that it is mostly working in your photo but there could be >>>>>> an >>>>>> issue with the specific section of the supply dedicated to the grid and >>>>>> it >>>>>> is referenced to the cathode. Although you have now replaced most of the >>>>>> potentially offending components unless you have an open winding on the >>>>>> transformer. You could check the resistance across pins 4,5 and 6 of the >>>>>> transformer. I'd expect them all to read fairly low. >>>>>> On Tuesday, October 26, 2021 at 10:20:26 AM UTC+10 GEK wrote: >>>>>> >>>>>>> Ok, so I'm stumped (again)... >>>>>>> >>>>>>> I have replaced D35-38, C52, C53, C54, C55, Q1, C51 and U17. >>>>>>> R67, F68, R69, R70 and R71 measure correctly in circuit. >>>>>>> I've confirmed pulsing on the BLNK- signal at 60hz >>>>>>> I've also swapped U5 (74HC74) and U4 (74HC151). >>>>>>> I've swapped the CRT. >>>>>>> >>>>>>> Curiously I need to have the Bright potentiometer (R11) at maximum >>>>>>
Re: [neonixie-l] Scope Clock SC200C
The brightness pot needing to be turned right up still suggests that you have a problem with grid voltage control. I'd expect to see some higher frequencies much higher than 60Hz on the BLNK- signal as well though. I'd be surprised if the problem was in the supply sections for the cathode or anode given that it is mostly working in your photo but there could be an issue with the specific section of the supply dedicated to the grid and it is referenced to the cathode. Although you have now replaced most of the potentially offending components unless you have an open winding on the transformer. You could check the resistance across pins 4,5 and 6 of the transformer. I'd expect them all to read fairly low. On Tuesday, October 26, 2021 at 10:20:26 AM UTC+10 GEK wrote: > Ok, so I'm stumped (again)... > > I have replaced D35-38, C52, C53, C54, C55, Q1, C51 and U17. > R67, F68, R69, R70 and R71 measure correctly in circuit. > I've confirmed pulsing on the BLNK- signal at 60hz > I've also swapped U5 (74HC74) and U4 (74HC151). > I've swapped the CRT. > > Curiously I need to have the Bright potentiometer (R11) at maximum to get > an image. > Could something in the High Voltage Supply be causing problems with the > blanking? > > On Thursday, October 21, 2021 at 3:05:10 PM UTC-4 Paul Andrews wrote: > >> Hah yes. I have one of its brethren that is even more 'eclectic'. >> >> On Wednesday, October 20, 2021 at 8:04:03 PM UTC-4 Terry S wrote: >> >>> >>> That may just be one of the worst PCB layouts I've ever seen. >>> On Wednesday, October 20, 2021 at 8:33:41 AM UTC-5 martin martin wrote: >>> >>>> Here's a simple one >>>> >>>> https://www.tindie.com/products/howchon/osc45-oscilloscope-clock-kit-for-many-crt-types/ >>>> >>>> >>>> >>>> >>>> >>>> ~ >>>> *mcve...@gmail.com* >>>> >>>> >>>> On Wed, Oct 20, 2021 at 4:16 AM GEK wrote: >>>> >>>>> Will do, Hopefully parts will be here by Friday. I may try and >>>>> shotgun D35-38 and C52-53 before then as I should have spares around here. >>>>> >>>>> Finger's crossed! >>>>> >>>>> - Gary >>>>> >>>>> On Wednesday, October 20, 2021 at 1:19:58 AM UTC-4 Tristan wrote: >>>>> >>>>>> Hi Gary, >>>>>> >>>>>> That's a bit odd. While I'm no EE I would have expected that removing >>>>>> U17 would have blanked the display if the rest of the circuit was >>>>>> working >>>>>> correctly. It looks Q13 should be conducting without U17 fitted and the >>>>>> grid should become more negative with respect to the cathode to ensure >>>>>> cutoff. I think you may need to look at the D35-38 and C52 & C53. >>>>>> >>>>>> - Tristan >>>>>> >>>>>> On Wednesday, October 20, 2021 at 12:42:53 PM UTC+10 GEK wrote: >>>>>> >>>>>>> Tristan - >>>>>>> >>>>>>> Thanks for those hints. the BLNK signal is pulsing at 60hz, and I >>>>>>> swapped Q13 without any change. I also socketed U17 (6N137) while >>>>>>> waiting >>>>>>> for a replacement to arrive. Removing U17 from the circuit leaves the >>>>>>> display unchanged, so it does appear that the blanking circuit is the >>>>>>> culprit. >>>>>>> >>>>>>> I'll swap U17 once it arrives - and if that doesn't fix things start >>>>>>> shotgunning the passives. >>>>>>> >>>>>>> Thanks again for the guidance, very appreciated! >>>>>>> >>>>>>> - Gary >>>>>>> >>>>>>> On Tuesday, October 19, 2021 at 10:04:24 PM UTC-4 Tristan wrote: >>>>>>> >>>>>>>> Also the voltage between the cathode and the blanking section >>>>>>>> should be checked (I.e. the voltage across C51) and R65 and R67 should >>>>>>>> be >>>>>>>> checked (or potentially replaced along with C51 if shotgunning it). >>>>>>>> The >>>>>>>> rest of the high voltage supply appears to be working. >>>>>>>> >>>>>>>> - Tristan >>>>>>>> On Wednesday, October 20, 2021 at 11:50:56 AM
Re: [neonixie-l] Scope Clock SC200C
Hi Gary, That's a bit odd. While I'm no EE I would have expected that removing U17 would have blanked the display if the rest of the circuit was working correctly. It looks Q13 should be conducting without U17 fitted and the grid should become more negative with respect to the cathode to ensure cutoff. I think you may need to look at the D35-38 and C52 & C53. - Tristan On Wednesday, October 20, 2021 at 12:42:53 PM UTC+10 GEK wrote: > Tristan - > > Thanks for those hints. the BLNK signal is pulsing at 60hz, and I swapped > Q13 without any change. I also socketed U17 (6N137) while waiting for a > replacement to arrive. Removing U17 from the circuit leaves the display > unchanged, so it does appear that the blanking circuit is the culprit. > > I'll swap U17 once it arrives - and if that doesn't fix things start > shotgunning the passives. > > Thanks again for the guidance, very appreciated! > > - Gary > > On Tuesday, October 19, 2021 at 10:04:24 PM UTC-4 Tristan wrote: > >> Also the voltage between the cathode and the blanking section should be >> checked (I.e. the voltage across C51) and R65 and R67 should be checked (or >> potentially replaced along with C51 if shotgunning it). The rest of the >> high voltage supply appears to be working. >> >> - Tristan >> On Wednesday, October 20, 2021 at 11:50:56 AM UTC+10 Tristan wrote: >> >>> I agree. The blanking is not working and as a result the beam is also >>> faintly visible as it moves quickly between the characters as well drawing >>> the arcs. It would be a good idea to check the BLNK signal on a scope and >>> at least see that is is toggling but my money would be on the analogue >>> blanking section. Given the other side of the optoisolator in the blanking >>> section is at a fairly high negative voltage potential (as this reduces the >>> need for the deflection amps to handle higher voltages) you will need to be >>> careful when probing around there but I would start by checking the >>> voltages across C54 and C55 (as long as you are confident doing so safely >>> with the HV potential to ground). The correct voltages aren't specified on >>> the schematic but they will be based on the grid cutoff voltage of the >>> tube. If you wanted to avoid probing while the clock is on I'd be inclined >>> to shotgun replace that section starting with the power supply diodes, caps >>> and Q13 and then U17 and finally the passives and see how you go. >>> >>> - Tristan >>> On Tuesday, October 19, 2021 at 4:24:11 PM UTC+10 iavine wrote: >>> >>>> From what I remember: >>>> the characters are generated from circles, ellipses or lines which in >>>> turn are created using sun or cosine waveforms >>>> To make a character the beam is blanked for certain parts eg C is a >>>> circle with a bit cut out. >>>> >>>> Looks like the blanking is not working as you’ve got a lot of circles >>>> and ellipses there. >>>> >>>> Looks cool though >>>> >>>> Cheers >>>> Ian V >>>> >>>> On 19 Oct 2021, at 06:08, Mac Doktor wrote: >>>> >>>> >>>> >>>> >>>> On Oct 18, 2021, at 7:53 PM, Gary Kaufman wrote: >>>> >>>> I've now got a stable, but scrambled display (see pic's). I think I >>>> have a problem with the shape generators but would appreciate any help or >>>> suggestions you could offer. >>>> >>>> >>>> Nah, that's just Cyrillic Neu Sans. >>>> >>>> >>>> Terry Bowman, KA4HJH >>>> "The Mac Doctor" >>>> >>>> "If only you could see what I've seen with your eyes."—Roy Batty, *Blade >>>> Runner* >>>> >>>> -- >>>> 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+...@googlegroups.com. >>>> To view this discussion on the web, visit >>>> https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com >>>> >>>> <https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com?utm_medium=email_source=footer> >>>> . >>>> >>>> -- 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/a94090c0-4c5c-4710-b9f7-a0736acc0947n%40googlegroups.com.
Re: [neonixie-l] Scope Clock SC200C
Also the voltage between the cathode and the blanking section should be checked (I.e. the voltage across C51) and R65 and R67 should be checked (or potentially replaced along with C51 if shotgunning it). The rest of the high voltage supply appears to be working. - Tristan On Wednesday, October 20, 2021 at 11:50:56 AM UTC+10 Tristan wrote: > I agree. The blanking is not working and as a result the beam is also > faintly visible as it moves quickly between the characters as well drawing > the arcs. It would be a good idea to check the BLNK signal on a scope and > at least see that is is toggling but my money would be on the analogue > blanking section. Given the other side of the optoisolator in the blanking > section is at a fairly high negative voltage potential (as this reduces the > need for the deflection amps to handle higher voltages) you will need to be > careful when probing around there but I would start by checking the > voltages across C54 and C55 (as long as you are confident doing so safely > with the HV potential to ground). The correct voltages aren't specified on > the schematic but they will be based on the grid cutoff voltage of the > tube. If you wanted to avoid probing while the clock is on I'd be inclined > to shotgun replace that section starting with the power supply diodes, caps > and Q13 and then U17 and finally the passives and see how you go. > > - Tristan > On Tuesday, October 19, 2021 at 4:24:11 PM UTC+10 iavine wrote: > >> From what I remember: >> the characters are generated from circles, ellipses or lines which in >> turn are created using sun or cosine waveforms >> To make a character the beam is blanked for certain parts eg C is a >> circle with a bit cut out. >> >> Looks like the blanking is not working as you’ve got a lot of circles and >> ellipses there. >> >> Looks cool though >> >> Cheers >> Ian V >> >> On 19 Oct 2021, at 06:08, Mac Doktor wrote: >> >> >> >> >> On Oct 18, 2021, at 7:53 PM, Gary Kaufman wrote: >> >> I've now got a stable, but scrambled display (see pic's). I think I have >> a problem with the shape generators but would appreciate any help or >> suggestions you could offer. >> >> >> Nah, that's just Cyrillic Neu Sans. >> >> >> Terry Bowman, KA4HJH >> "The Mac Doctor" >> >> "If only you could see what I've seen with your eyes."—Roy Batty, *Blade >> Runner* >> >> -- >> 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+...@googlegroups.com. >> To view this discussion on the web, visit >> https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com >> >> <https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com?utm_medium=email_source=footer> >> . >> >> -- 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/5bbcfc03-24d0-4ba5-b185-8c41f9b7bfeen%40googlegroups.com.
Re: [neonixie-l] Scope Clock SC200C
I agree. The blanking is not working and as a result the beam is also faintly visible as it moves quickly between the characters as well drawing the arcs. It would be a good idea to check the BLNK signal on a scope and at least see that is is toggling but my money would be on the analogue blanking section. Given the other side of the optoisolator in the blanking section is at a fairly high negative voltage potential (as this reduces the need for the deflection amps to handle higher voltages) you will need to be careful when probing around there but I would start by checking the voltages across C54 and C55 (as long as you are confident doing so safely with the HV potential to ground). The correct voltages aren't specified on the schematic but they will be based on the grid cutoff voltage of the tube. If you wanted to avoid probing while the clock is on I'd be inclined to shotgun replace that section starting with the power supply diodes, caps and Q13 and then U17 and finally the passives and see how you go. - Tristan On Tuesday, October 19, 2021 at 4:24:11 PM UTC+10 iavine wrote: > From what I remember: > the characters are generated from circles, ellipses or lines which in turn > are created using sun or cosine waveforms > To make a character the beam is blanked for certain parts eg C is a circle > with a bit cut out. > > Looks like the blanking is not working as you’ve got a lot of circles and > ellipses there. > > Looks cool though > > Cheers > Ian V > > On 19 Oct 2021, at 06:08, Mac Doktor wrote: > > > > > On Oct 18, 2021, at 7:53 PM, Gary Kaufman wrote: > > I've now got a stable, but scrambled display (see pic's). I think I have > a problem with the shape generators but would appreciate any help or > suggestions you could offer. > > > Nah, that's just Cyrillic Neu Sans. > > > Terry Bowman, KA4HJH > "The Mac Doctor" > > "If only you could see what I've seen with your eyes."—Roy Batty, *Blade > Runner* > > -- > 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+...@googlegroups.com. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com > > <https://groups.google.com/d/msgid/neonixie-l/3FBEDB26-E97C-44E2-B088-BDA7DAE4A020%40gmail.com?utm_medium=email_source=footer> > . > > -- 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/f4b9e20a-d7e1-448b-b5a4-174a4d2eccd9n%40googlegroups.com.
[neonixie-l] Re: Dot matrix display
I started development of a clock using some similar displays (except 256x64 pixels). https://sites.google.com/site/tristansideas/electronics/pinball-display-clock Sadly a lack of time has prevented me from finishing the project so far. They can pretty much be driven from the SPI peripheral of most micros. I used an MSP430 for testing. This allowed each row of display data to be shifted in using one of the DMA channels with minimal interrupt/CPU usage just to latch each row keep track of the number of rows. I was able to achieve 4 levels of grey pretty easily. The chip on the dev board I used didn't have RAM to hold the entire frame buffer so I was using an external SPI SRAM (also DMA driven). This was not intended to be the long term design and I would use a part with enough RAM on board. I've been thinking of driving them from a BeagleBone Black. Simply because the PRU's available would be capable of doing the real time processing required. Trammel Hudson used this method to drive a Mac-SE display and only minimal changes would be required to run a DMD. https://trmm.net/Mac-SE_video That's not to discourage the use of an FPGA. Even without one I was able to exceed the 200Hz maximum using the MSP430 (they still seem to work at > 200Hz). These displays do use a fair amount of power. They can get warm. They also have a tendency to produce a high pitched whine when operating. They did run in pinball machines in arcades pretty much non-stop but they do wear out eventually. There are LED based replacements available now but that lacks a certain something that you can only get from neon. -- 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/354a9fb0-9304-4e9e-913e-e24a1df5f38a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[neonixie-l] Re: IV-17 tube filament voltage difference (DC drive)
If the transformer lacks a real center-tap then a virtual center-tap can be used instead. Simply use a pair of resistors of a reasonable value, say 470ohm as a divider across the secondary of the transformer and use the center of the divider instead to bias the cathodes instead. If you were running an even number of tubes in series you could use the middle filament connection instead. On Sunday, November 15, 2015 at 7:17:16 AM UTC+10, Chaos Hydra wrote: > > yeah, that's what I need to do next, reduce the background illumination of > those tubes. I will look into this. Thanks. > > On Saturday, November 14, 2015 at 4:33:27 AM UTC-5, Dekatron42 wrote: >> >> I am glad it works better now! >> >> Have a look at paragraph 6.2 in the Noritake link, there they use a zener >> diode to bias the center tap, you can usually just use a string of ordinary >> diodes to try out what bias voltage that you need for your design to have a >> proper cut-off voltage. >> >> Then when you know that cut-off voltage you can either use one zener with >> the nearest voltage or you can use two (or a string of diodes) and then you >> can short part of this diode chain to have an effective dimming capability >> - the Russians (probably others too) used this way of dimming the VFD >> displays in clocks for night usage. >> >> So using a center-tapped transformer has its good sides. >> >> /Martin >> >> On Saturday, 14 November 2015 03:30:41 UTC+1, Chaos Hydra wrote: >>> >>> I made a clean cut on the trace and patched in a 10VAC transformer. That >>> solved the overheating filament problem and now has a decent brightness >>> overall. The only problem is: the certer tubes' "off segments" are quite >>> bright. It is kind of difficult to read sometimes. >>> >>> On Friday, November 13, 2015 at 2:52:28 AM UTC-5, gregebert wrote: It's worth trying 1 cut between the 12VDC supply and the filament chain, and applying AC between GND and the cut-trace. It may not give you the best results, but it could produce less variation in brightness. -- 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/5521c211-e766-4c0f-85a5-82353b78b3f5%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [neonixie-l] Re: Any one have a dutchtronix kit or PCB?
If they fail that quickly and the damage is concentrated in the center then it sounds like it could be also be ion damage to the phosphor as opposed to an issue with the phosphor itself. I'm not sure how good the vacuum is on some soviet tubes in general (I suspect it varied from factory to factory if not day to day) and most electrostatic CRT's of this era don't seem to have an an aluminium layer or an ion trap to protect the phosphor. On Wednesday, June 3, 2015 at 6:46:45 PM UTC+1, petehand wrote: I was shishlakji on the old group, it's the same clock. Here is the schematic. The M62354 DAC may need a little explanation. It's a voltage output serial input DAC. The voltage reference is floating - does not need to be ground at one end - this is unusual in DACs. Here the reference is the voltage across diode D7. I jacked it up off ground for proper biasing of the long tail pairs, but I ended up giving them a negative supply, so any old DAC would do now. I have no idea where you could get a M62354 today -I just happened to have some in my junk box. The 3LO1 tube life is definitely a phosphor problem. The phosphor layer is so thin it's practically transparent and the brightness fades from the center, where the beam traces over it most frequently. Towards the end of life the center doesn't glow and only the tips of the hands are visible. I don't know what such a short life tube could have been used for - perhaps an instrument on a weapon when they expected the next war to be over in 24 hours. -- 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/9cc90220-c884-4090-9fa2-1ca8dd6b9733%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [neonixie-l] Sputtering ?
Beat me to it. I have observed this affect on ZM1040 tubes. -- 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/732d69fc-13b5-4389-ab62-ab593e2fa8c4%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[neonixie-l] Re: ZM1251
I've had some success with a 256 x 64 version of one of these displays. https://sites.google.com/site/tristansideas/electronics/pinball-display-clock You can achieve grayscale by using several sub-frames. It's a pity there hasn't been much spare time to work on that particular project and finish it off. On Thursday, July 11, 2013 7:49:18 AM UTC+10, greg...@hotmail.com wrote: I'm posting the datasheet I found on the web for the 128x32 display, manufactured by Vishay. Nixie tubes contain a single anode, and multiple cathodes that glow. The neon matrix device uses multiplexed anodes and cathodes. To illuminate pixels, a single particular row is energized, and so are the columns for each pixel that is to be illuminated. The electric field around an energized row is not sufficient in itself to illuminate a pixel (same is true for a column). But when an energized row meets an energized column, there is sufficient field-strength to initiate a discharge. I believe that adjacent unenergized rows and columns have low-enough leakage so that a discharge cannot spread. You may recall that the sustaining field for a discharge is significantly lower than required to initiate it. -- 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/93a746bc-6ad0-48bd-8df0-67f414418c89%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Dekatron frequency counter and 6909 issue
I have one 6909 and have been wondering the same thing. There is a section on gas permeation in the book Vacuum Sealing Techniques by Alexander Roth and from reading it would seem that while the hydrogen can permeate the glass envelope, the low pressure within means that gasses (helium and neon in particular) can more readily permeate into the glass envelope from the outside atmosphere. Lower temperatures will certainly reduce the rate of permeation but increasing the pressure (with compressed air at least) would probably just lead to increased contamination of the internal gas fill with atmospheric gasses. I would think the best way to preserve the fill would be to have the same atmosphere external to the envelope as there is internally (not so easy). Failing that, keeping them cold should help but I wouldn't expect miracles. -- 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/10f2fd5e-50c5-4d53-b034-e54a1f73f6cc%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] B-7971
It's probably wishful thinking but I'd like to track down a single B-7971. I'm in the process of building a clock and one of four tubes I have is a little reluctant on a couple of segments. Perhaps it can be revived with some extra current? https://lh3.googleusercontent.com/-8NEKtUWdNM0/UT7EOGsMeRI/AAM/1fztdRJxA4I/s1600/8543980711_ddb29c28ad_k.jpg -- 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/-/iC0UiX-ppGoJ. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Looking for VFDs
Have you seen here? http://store.reuseum.com/Itron_Noritake_FG165S1_VFD_p/noritake-07-001.htm -- 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/-/Q-cNAjVG2kgJ. For more options, visit https://groups.google.com/groups/opt_out.
[neonixie-l] Re: Photographing VFDs...
My first nixie/vfd photos were terrible. Recent attempts have been much better. There's some great advice here already but I figured I'd throw in my 2c. As stated you need to adjust the lighting to the level required to correctly expose the rest of the structure and set up the camera to correctly expose the lit segments. I used well diffused off camera flashes for this but lamps would work too. Something like a sheet of thin paper can be used as a makeshift diffuser in that case. Moving the lamps to adjust the levels. The other advice I would offer is to stop down the lens a fair way (set a high f number) so the depth of field is as wide as you can get it (there are limits that affect sharpness but usually it's not a problem). This will ensure as much of the tube is in sharp pfocus as possible. Without a flash it will probably result in a longer exposure time so a tripod or some way to steady the camera is a good idea. - Regards, Tristan -- 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: Nixie tube photographing
Having spent some time photographing the IN-18 blue dot phenomenon I can say that it is a matter of balancing the ambient (or flash) light with the emitted light. If getting up close it is a good idea to manually set a small aperture (high F number) and using a longer exposure so the depth of field is maximized. Using the aperture priority mode and tweaking the exposure compensation is ideal for this purpose. As stated, a tripod is also highly recommended. Particularly with the longer exposure. Here are some sample images: http://home.people.net.au/~technics/IMG_8152.JPG http://home.people.net.au/~technics/IMG_8157.JPG http://home.people.net.au/~technics/IMG_8174.JPG http://home.people.net.au/~technics/IMG_8176.JPG These were taken with the camera on a tripod using natural light on one side and a diffused external flash on the other. The output of the flash was adjusted to balance the emitted and reflected light as desired. Hope that helps. -- 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.
