[neonixie-l] Re: SP-431 panaplex displays, looking for opinions on whether to desolder from module

[ZY]

I think they are these 
displays: https://www.tubeclockdb.com/on-ebay/179-babcock-sp-431
The camera angle is not great but yea the displays are quite big, with like 
2" high digits.

Good point with the socketed ICs. I might try that route first before 
soldering, but I'll also try to map out some of the input side to see what 
the actual logic is (if it counts or it's decoding or something).

In the end though if the actual PCB itself is not some valuable vintage 
thing, I'd rather desolder the it for my own clock as I can get a better 
form factor. The whole thing is very big, a bit dirty, and is very heavy so 
it doesn't really make a good display piece as is.
On Monday, 23 October 2023 at 12:24:40 UTC-4 gregebert wrote:

> NICE FIND !!! 
>
>   Based on the size-comparison with the DIP ICs/resistors, these look like 
> large displaysmaybe 2 inches tall ? If they really are that big then 
> you definitely want to make a gizmo, probably a clock, with these. It looks 
> like they are direct-drive, and since the IC's appear to be socketed you 
> might be able to remove them and do some individual segment testing to see 
> how healthy the displays are before you start the process of 
> reverse-engineering or redesigning a new board.
>
>
> On Monday, October 23, 2023 at 7:03:05 AM UTC-7 leo oel wrote:
>
>>
>> Hello
>> I made a "Clock" on a similar one, only I have the model SP-494 and SP-492
>> https://twitter.com/leoloel/status/1662535750393495552
>> a few photos
>> понедельник, 23 октября 2023 г. в 16:43:29 UTC+3, Adam Piórko: 
>>
>>> It looks like VFD displays. If the "plus" is lit, the module seems to be 
>>> functioning properly. If you enjoy reverse engineering, you can try to make 
>>> a clock from this module. Two things need to be discovered.
>>>
>>>1. How to send a digit? If it's a counter, it might be challenging. 
>>>Incrementing by +1 might be too slow, and digit changes will be visible.
>>>2. It's unknown if there's a reset to zero (reset function) - if 
>>>not, you'll have to add up to 99. 
>>>
>>> You can make a 24-hour clock out of it. There's no "AM/PM" - unless you 
>>> add it on the side or skip it.
>>>
>>>
>>> niedziela, 22 października 2023 o 13:47:29 UTC+2 ZY napisał(a):
>>>
>>>> Pictures attached
>>>>
>>>>

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[neonixie-l] SP-431 panaplex displays, looking for opinions on whether to desolder from module

[ZY]

Hello. I have this old and dusty module that contains 2x SP-431 panaplex 
displays. They seem to still have gas in them, but I can only get the plus 
sign and some keep-alive dots to turn on as I don't know the low-level 
logic of the module.

I'm wondering if I should just desolder the displays to use in a clock, or 
not desolder and try to restore functionality to the whole module? IMO I 
don't think the module itself has any value, and I think it's some counter 
for some lab equipment so it wouldn't really work for any clock even if I 
figure out the communications. But just in case it has any historical 
significance I'd thought I'd ask here first.

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Re: [neonixie-l] Re: AC VFD Filament Driver Question

[ZY]

On Sunday, 16 April 2023 at 02:50:44 UTC-4 petehand wrote:

I use H bridges for my VFD designs. The VFD heaters are designed to run as 
slow as 50Hz, as the thermal inertia is more than sufficient for a steady 
display. There will be no beating. I generally run them at about 200- 500 
Hz. The bias needed is negligible, just enough to make the anodes slightly 
negative relative to the heater - 1 volt is usually plenty. It is, as you 
say, equivalent to half the P-P AC voltage.


 What is your strategy for biasing, are you pulling the anodes negative or 
are you adding a DC bias to the filaments? I'd prefer not having to have a 
separate negative power supply so a positive bias on the filaments is 
ideal, but I'm not sure how to DC bias the h-bridge, I'm imagining a zener 
at the h-bridge ground would do it? I guess the problem is my H-bridge is 
an integrated IC, so it's Vout ground and digital ground are tied, adding a 
zener to the IC ground might mess with the digital logic.

I tried adding a zener for my transformer to bias it and it seems to work 
here with a simulated 30V grid being turned on:
https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIeMDIWBBJwLIiylRx5WWY6+oaWMGhSAixato7MNBwwWEgiWooXBApiGkUESCo+2DpcSCxqMchFLFgsMmsELEg2rFHcNhxmGIkFf3EiMiIE8WTYisK8ihkRIMfXnwkvnalgohfRxXIGwW5RR43O7ZaEPGGXViQRgIuF0ZFZJBZRD-WJoyogESZHHQ+IlPLE3T6PSlKlwsl6BjU0S5M54hGE2FnDnsxkornrfH2dHE+mk0rYoJpNkYpGw86pAkCiXc3LytJCwW81X5R4XDFYrLJaggABeKAAdigUmgILboJBiMD4LZ4PIEOhVtIWsYfcYweBwDwTT9xFMQaGBeIzZbrbxhi9Q5BwyBgQGomkKvEnkIOBQ5DwAEoprQSTBURg2gyBUp5wKRaBqAAOUB2+KT0hrdeC7aZLekSa7sQ1Ep7EuSAGdzuTi4wkoEAGYAQwANuOUGdM5hrrckgrt6WJFDdLn85Dbrp93zdb4rnr-gB7QIQURIay0VjKQL3FM8R9sZ96FgkhuLIkwBuIbBuAAYgAlsui4ALYWgALr+H4QKsYCOGA9Afr0ehptAZDIGhtYASQ+BGIoEAgSAABCMGLmuAAmAA644AGpoPOcGIShaFTGm4DYUUazyEiCCuLgNBjMg4BERIBGCW4DFMWgADGACuKQpPxQA

A DAC with an opamp buffer on the center tap would be interesting, but 
wouldn't that opamp be taking a lot of current with some larger VFDs?


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[neonixie-l] Re: AC VFD Filament Driver Question

[ZY]

I'm playing around a bit more with some active filter designs so it won't 
be load dependent, but 100khz seems a bit high for this application. Going 
a lower frequency would require I select a different/larger transformer 
since my current would be too high.
On Saturday, 15 April 2023 at 03:26:46 UTC-4 ZY wrote:

> I wanted to try to avoid having a AC line in my design if possible. I did 
> have to break out my old ECE notes, and I designed a different filter. 
> Turns out my original RC filter requires a much larger resistor to limit 
> the primary side current, but that raises input resistance too high for my 
> 40 ohm loads.
>
> Using a different filter I had some more success:
>
> https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIeMDIWBBJwLIiylRx5WWY6+oaWMGhSAixato6zfzIiESJuJCxIWoRIEDQcYiwKSHbIMgQqWDkRiamSWfnF5bkqRWYYiQV-cT6iBPFkgSIKcRK8u70sKuPwQMjoNViKwseZERBH5PP4SJ4IF5BLy3e6lGF6SBXIESXqXbJo5IAYxRF0QmHOGL0lghxlJ8gQ6HG1RGuBGiGYFFsGUIyKQWVOrAWGKOdEYePR-OSsV5lRAIkyUiOHPiDwkktiun0elKSqFyukDHV3OFXI54u1Yshes1HLV+v59j5WTVsplpUFPAANjjRWyJR8WsZMJMWgwiCMEORbrBqBQhMlnb9yqjBYpjCVFNMtmAFksKCssJQgmkRfzc7ljqlDe7zQX8mlLaLK6bCwB7QIQURIay0ViKC6GDgUHj1tiN56SNwIL5xvt6Nvd3vvcZgRwpthsKbjxstSDwZA8IA
>
> However the problem is the output voltage is somewhat determined by the 
> load. So if a filament burns out it can cause a cascade failure on the 
> other filaments as the voltage rises. I guess monitoring the AC line would 
> be possible but this complicates my design a bit, and I'd need a monitor 
> that could do negative currents/voltages if my bias is not high enough. If 
> such an IC exists I'd be interested, but I don't really have access to a 
> FPGA if that's what it takes.
>
> It also seems it's easy to hit resonance with particular filter LC values, 
> boosting the voltage higher which feels a bit dangerous for the filaments.
>
> Maybe just not having the filter would be the safest approach here. 
> However I'm not at all experienced in filter design especially when there 
> is a low impedance load involved, so maybe there's a better approach that 
> I'm not using.
>
> On Saturday, 15 April 2023 at 02:03:39 UTC-4 gregebert wrote:
>
>> I use a mains-powered 2.5VAC center-tapped transformer for my NIMO clock, 
>> and apply a DC bias to the center-tap. Basically the same as your approach, 
>> but not running at 100kHz. The DC bias comes from a DAC (with an OP-amp 
>> buffer), so I can use software to control the offset, rather than a pot. No 
>> need for LC filters, etc.
>>
>> The transformer is rated at 3amps, even though 6 NIMO tubes only require 
>> 1.2amps max. Also, each tube has it's own fuse and series resistor to 
>> reduce the inrush current. The software-controlled DAC is also necessary so 
>> I can have the FPGA monitor analog signals to check the fuses, filaments, 
>> and resistors, and that has to be timed correctly to the AC line and the 
>> offset has to be different for making these measurements than for regular 
>> operation. It was probably overkill, but I enjoyed the design challenge.
>>
>> On Friday, April 14, 2023 at 2:25:57 PM UTC-7 ZY wrote:
>>
>>> Hello. I'm working on a driver for my VFD filaments. Say I need a 
>>> Vfilament of 1.6V, and a current of 40mA, such as with a small VFD.
>>>
>>> So far I have a square wave driver set up, basically for my two filament 
>>> pins I can alternate the two pins between 1.6 and 0 with some H bridge at 
>>> maybe 100KHz. If I connect the filament load to this, it's the equivalent 
>>> of using a 3.2V Vpp square wave biased at 0v. See Sim Link 1. I put two 40 
>>> ohm resistors as a stand in for 2 VFD tubes filaments in parallel.
>>>
>>> However, I'd like to add some sort of smoothing and DC bias. I was 
>>> thinking of using a small transformer, such as this one:
>>> https://www.mouser.com/datasheet/2/445/750315240-3096542.pdf
>>> Applying a 100KHz RC low pass filter to the output, and approximating 
>>> the turn ratio at 1:1 (it's 1:1.1 in the datasheet but ignoring that for 
>>> now), I have a simulation below as Sim Link 2.
>>>
>>> The problem here is I seem to be wasting a huge amount of power just 
>>> driving the transformer on the primary size. The plot on the very far left 
>>> shows I'm delivering 2.2A to the transformer. I guess I could find a larger 
>>> transformer with a higher inductance, or increase my switching frequency, 
>>> but I'm not sure if I'm on the right design path here.
>>>
&

[neonixie-l] Re: AC VFD Filament Driver Question

[ZY]

I wanted to try to avoid having a AC line in my design if possible. I did 
have to break out my old ECE notes, and I designed a different filter. 
Turns out my original RC filter requires a much larger resistor to limit 
the primary side current, but that raises input resistance too high for my 
40 ohm loads.

Using a different filter I had some more success:
https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIeMDIWBBJwLIiylRx5WWY6+oaWMGhSAixato6zfzIiESJuJCxIWoRIEDQcYiwKSHbIMgQqWDkRiamSWfnF5bkqRWYYiQV-cT6iBPFkgSIKcRK8u70sKuPwQMjoNViKwseZERBH5PP4SJ4IF5BLy3e6lGF6SBXIESXqXbJo5IAYxRF0QmHOGL0lghxlJ8gQ6HG1RGuBGiGYFFsGUIyKQWVOrAWGKOdEYePR-OSsV5lRAIkyUiOHPiDwkktiun0elKSqFyukDHV3OFXI54u1Yshes1HLV+v59j5WTVsplpUFPAANjjRWyJR8WsZMJMWgwiCMEORbrBqBQhMlnb9yqjBYpjCVFNMtmAFksKCssJQgmkRfzc7ljqlDe7zQX8mlLaLK6bCwB7QIQURIay0ViKC6GDgUHj1tiN56SNwIL5xvt6Nvd3vvcZgRwpthsKbjxstSDwZA8IA

However the problem is the output voltage is somewhat determined by the 
load. So if a filament burns out it can cause a cascade failure on the 
other filaments as the voltage rises. I guess monitoring the AC line would 
be possible but this complicates my design a bit, and I'd need a monitor 
that could do negative currents/voltages if my bias is not high enough. If 
such an IC exists I'd be interested, but I don't really have access to a 
FPGA if that's what it takes.

It also seems it's easy to hit resonance with particular filter LC values, 
boosting the voltage higher which feels a bit dangerous for the filaments.

Maybe just not having the filter would be the safest approach here. However 
I'm not at all experienced in filter design especially when there is a low 
impedance load involved, so maybe there's a better approach that I'm not 
using.

On Saturday, 15 April 2023 at 02:03:39 UTC-4 gregebert wrote:

> I use a mains-powered 2.5VAC center-tapped transformer for my NIMO clock, 
> and apply a DC bias to the center-tap. Basically the same as your approach, 
> but not running at 100kHz. The DC bias comes from a DAC (with an OP-amp 
> buffer), so I can use software to control the offset, rather than a pot. No 
> need for LC filters, etc.
>
> The transformer is rated at 3amps, even though 6 NIMO tubes only require 
> 1.2amps max. Also, each tube has it's own fuse and series resistor to 
> reduce the inrush current. The software-controlled DAC is also necessary so 
> I can have the FPGA monitor analog signals to check the fuses, filaments, 
> and resistors, and that has to be timed correctly to the AC line and the 
> offset has to be different for making these measurements than for regular 
> operation. It was probably overkill, but I enjoyed the design challenge.
>
> On Friday, April 14, 2023 at 2:25:57 PM UTC-7 ZY wrote:
>
>> Hello. I'm working on a driver for my VFD filaments. Say I need a 
>> Vfilament of 1.6V, and a current of 40mA, such as with a small VFD.
>>
>> So far I have a square wave driver set up, basically for my two filament 
>> pins I can alternate the two pins between 1.6 and 0 with some H bridge at 
>> maybe 100KHz. If I connect the filament load to this, it's the equivalent 
>> of using a 3.2V Vpp square wave biased at 0v. See Sim Link 1. I put two 40 
>> ohm resistors as a stand in for 2 VFD tubes filaments in parallel.
>>
>> However, I'd like to add some sort of smoothing and DC bias. I was 
>> thinking of using a small transformer, such as this one:
>> https://www.mouser.com/datasheet/2/445/750315240-3096542.pdf
>> Applying a 100KHz RC low pass filter to the output, and approximating the 
>> turn ratio at 1:1 (it's 1:1.1 in the datasheet but ignoring that for now), 
>> I have a simulation below as Sim Link 2.
>>
>> The problem here is I seem to be wasting a huge amount of power just 
>> driving the transformer on the primary size. The plot on the very far left 
>> shows I'm delivering 2.2A to the transformer. I guess I could find a larger 
>> transformer with a higher inductance, or increase my switching frequency, 
>> but I'm not sure if I'm on the right design path here.
>>
>> Also, it seems like some of my issues stem from my LC filter. If I remove 
>> that, the simulation shows more reasonable primary currents of 100mA. See 
>> Sim Link 2. I don't really remember my ECE courses from a long time ago, so 
>> I'm not sure what is going on here.
>>
>> Anyone have any suggestions?
>>
>>
>> Sim Link 1:
>>
>> https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAH

[neonixie-l] AC VFD Filament Driver Question

[ZY]

Hello. I'm working on a driver for my VFD filaments. Say I need a Vfilament 
of 1.6V, and a current of 40mA, such as with a small VFD.

So far I have a square wave driver set up, basically for my two filament 
pins I can alternate the two pins between 1.6 and 0 with some H bridge at 
maybe 100KHz. If I connect the filament load to this, it's the equivalent 
of using a 3.2V Vpp square wave biased at 0v. See Sim Link 1. I put two 40 
ohm resistors as a stand in for 2 VFD tubes filaments in parallel.

However, I'd like to add some sort of smoothing and DC bias. I was thinking 
of using a small transformer, such as this one:
https://www.mouser.com/datasheet/2/445/750315240-3096542.pdf
Applying a 100KHz RC low pass filter to the output, and approximating the 
turn ratio at 1:1 (it's 1:1.1 in the datasheet but ignoring that for now), 
I have a simulation below as Sim Link 2.

The problem here is I seem to be wasting a huge amount of power just 
driving the transformer on the primary size. The plot on the very far left 
shows I'm delivering 2.2A to the transformer. I guess I could find a larger 
transformer with a higher inductance, or increase my switching frequency, 
but I'm not sure if I'm on the right design path here.

Also, it seems like some of my issues stem from my LC filter. If I remove 
that, the simulation shows more reasonable primary currents of 100mA. See 
Sim Link 2. I don't really remember my ECE courses from a long time ago, so 
I'm not sure what is going on here.

Anyone have any suggestions?


Sim Link 1:
https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIYiQV-cSIyIgTxZNjS8sRMJCy6oOqyiuy25LS6RibujsKChpzxPuLm1kgerKHwLKq2+IQSCSkC3X09ZY35pekGTdFcgt3ZzAjT8fOxk7H5q6yai53lxeWm5IB7QIhRJGtaViKcqGDgUHhfNg-PRYSRuBDQNg4LCQvSAsEQ8BQcCOMD0QE4CAyRRYSDwZA8IA

Sim Link 2:
https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIeMDIWBBJwLIiylRx5WWY6+oaWMGhSAixato7MNGbEWAYsCgRZMGosLOaseiIie2ItSARSGRbp2aR5skXhokVmGIkFf3FZ3eOggSIhvVKr8SWqw-BAyOg1WIrCvOuvoI+fkQSa4PIJeO43b73RYvA6nSrZeHJAAOIBEmUwaL0DBAbiiXkx+lRWEwCGhUQ+ZDOASQE1yqUOonKlMR4B4AGMJMy+pyqeJXsZ2oxmrAtHZ4IMiIRILpqu16XQhVkFQk+YcDjScuJledkrFtUqJlldaxIIqMcTEQdzvESnkpFahITbViDAdnU7Sjr2RCJCTPUbFMYIDgiIgMuQyKT8JJyIG5QB7QLB8AbWhsNgWVWqig8RNsZNLSRuBBvRQQCBanG51jPSDgRxgeg1nAV54thjIaujNuHfDNyw41lAA

Sim Link 3, no LC Filter:
https://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCDsB0AcYCYCsBTAtLEAGaBOWuYALFrgGwDMFRSSkSZIuuISrWr6YYAUAG7hE4Mh24IQRTB3FgscudjiKpipP0HiKZTGJDJG08PIU4pSitGJgkuBGSQUkBSLgqqeAcw3DRQsLexsT28tHSESDkieAHdvSXAA+KweACdWBB0M9J0AjhIeMDIWBBJwLIiylRx5WWY6+oaWMGhSAixato6zRGsiOyJILApEXEgyCDRq2AQKWG1ISAQ7OhE2SZbp2fnF5bGhxWYYiQV-cSIyIgTxZIEiCnESvPu9LCrj8EDI6DVYisKnmQiIK-Z7-CTPBCvIJeO4PUqwvSLT5Hc6XRCYJBZdFBAAOIBEmUwBL0DBAbiiXmJ+nxUIQSKivwuV2yzOSaRWlVYY1ZxyOmJy4g5p2BXMY2P5nOSsSFWWJ2KlzPijwkUiOumpyupCs1pOVwuSAGM9PDMHqsl9jBApmQRAhRhQsJJRrgsNcWu0USdykz5TwAPaBK3gJDWWisRSXQwcCj+8NByGSNxsHAyPThmMBtgQSDgRxgejhnAQVM4MjIWNgNxBkj4QuWMngHhAA

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Re: [neonixie-l] Re: Nixie Clock - Direct Drive HV5530

[ZY]

Don't numitrons have pretty high shoot-through current? I'd expect 100mA of 
current going into the IC pins at each off-on transition. Which would 
probably be fine since it's only for a few milliseconds and as you 
mentioned it's been fine for years, but it's technically out of spec.

On Monday, 15 August 2022 at 13:56:56 UTC-4 Mark Moulding wrote:

> I almost invariably use daisy-chained 74HC595s in my clocks.  I use 
> Numitrons rather than Nixies, which can be direct-driven with 5 volts, and 
> an 8051 variant (AT89C4051) because I have lots of them and a tool chain 
> I'm comfortable with; they're programmed in C.  To drive the clock, data, 
> and load lines, I just directly bit-bang the micro outputs in code, and the 
> '595s are fast enough that I don't need to worry about timing - I just go 
> as fast as I can.  I never bothered to do a timing analysis because I 
> figured I wasn't at all close to the timing limits of the parts.  Another 
> pin from the microprocessor is used to apply a PWM signal to the output 
> enable of the '595s to provide dimming of the display.
>
> Also, the '595s have a high output drive capability - they're rated at 35 
> mA, so driving the individual segments of the Numitrons (~20 mA each) is no 
> problem.  I have many thousands of hours on several different clocks, over 
> more than a decade, with zero failures of either the drivers or the tubes.  
> (Occasionally, I'll lose a power supply...)
> ~~
> Mark Moulding
>
> On Monday, August 15, 2022 at 7:46:03 AM UTC-7 nixiebunny wrote:
>
>> The most sensible low-cost direct drive arrangement in terms of parts 
>> count and board layout is SOIC 74HC595 shift registers and SN75468 HV 
>> driver arrays. 
>> There's a Chinese Zirrfa 6 digit clock board that uses this approach. 
>>
>>
>> On Mon, Aug 15, 2022, 7:09 AM David Pye  wrote:
>>
>>> Given the price of these custom drivers, I wonder whether some cheap arm 
>>> microcontrollers with serial interface and mpsa42 type transistors would be 
>>> a decent replacement.  
>>>
>>

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Re: [neonixie-l] eBay Paranoia

[ZY]

I've been buying from ebay/aliexpress/etsy with no issues, I probably have 
500+ transactions over the past 10 years. But as with all internet orders, 
I do have the occasional missing item or broken item sent to me. I've 
gotten my money back every single time, ebay/aliexpress would 99% of the 
time side with the buyer and they'll give you an instant refund.

I also sell on ebay, I think they give you the option now for fees like 
shipping costs to be deducted directly from the sale instead of debting 
from the bank.

I would trust these large internet vendors with my CC info more than the 
restaurant I go to tbh, these large companies have been operating for years 
and have millions of dollars pouring into security. The restaurant nearby 
who takes my credit card could just be skimming my info at the counter for 
all I know. I guess it's a US thing, in Canada they bring the small 
handheld CC machine to you so your CC never leaves your hands.

On Sunday, 3 April 2022 at 07:31:59 UTC-4 Robert G. Schaffrath wrote:

> My biggest issues with eBay in the past were not receiving and item though 
> it was a rare occurrence. I would contact eBay and they would tell me to 
> contact PayPal. Contacted PayPal and they would tell me to contact eBay. 
> One big circle j__k. Since the amounts had been under USD$10, I just wrote 
> it off. But it has always made me very leery of buying anything on eBay 
> though I have not had any issues for many years. When I first opened my 
> PayPal account, I too worried about them having my checking account. In the 
> end, I opened a second checking account at a different bank right near me 
> where I already had a savings account. I keep very little money in the 
> account as I can easily transfer money from savings to checking as needed 
> (I think back to when I was kid in the 1960's and my father would drive to 
> the savings bank, take out money and then drive to the commercial bank to 
> put it in the checking account - glad that is a thing of the past). As 
> such, there is very little PayPal, or now eBay, can take from me if they 
> are hacked or just decide they want some money for some reason.
>
> On Saturday, April 2, 2022 at 12:10:32 PM UTC-4 SWISSNIXIE - Jonathan F. 
> wrote:
>
>> I've never had problems with payments on ebay so far, but i have to admit 
>> that i think ebay is getting worse and worse every day.
>> My biggest issue is that ebay is actively hiding items that can't be 
>> delivered to your address. I have multiple addresses for shipping, but only 
>> the primary one is considered valid at searches. Its a pain switching 
>> between 3 addresses to see "all" items for a specific search.  Not to 
>> mention the ridiculous forced translations they do since a while ago...
>>
>> On Saturday, 2 April 2022 at 00:39:29 UTC+2 Jim KO5V wrote:
>>
>>> Thanks to everyone who responded. I am very frustrated with eBay, since 
>>> I get an email every couple of weeks telling me that "action is required to 
>>> put my account back in good standing". It sounds like I am a deadbeat, 
>>> rather than a paying customer.
>>>
>>> I had considered opening a 'for internet use only' bank account, but 
>>> giving out my social security number is probably always going to be the 
>>> real problem. It might already have been compromised, but I guess I just 
>>> don't want to volunteer any more information than is necessary.
>>>
>>> As I get older, I am wanting to simplify. eBay is convenient, but there 
>>> are ham radio sites, etc where I can sell my treasures, so except for the 
>>> occasional purchase, I'm  probably done with eBay - after almost 25 years.
>>>
>>>  Best regards, Jim
>>>
>>>
>>>
>>> On Friday, April 1, 2022 at 7:24:15 AM UTC-6 Paul Andrews wrote:
>>>
 @threeneurons, that is very sensible. As someone who had their identity 
 stolen I am very wary about any of this. BTW 'stolen identity' does not 
 mean they got my credit card info. It means they got my identity and went 
 around opening their own credit cards in my name, using my address and my 
 social security number. This year we found out that my son also got his 
 identity stolen - someone filed their taxes using his information (I still 
 don't see the benefit of that).

 Anyway, I stopped selling online after paypal sent me a 1099. The extra 
 hassle filing taxes isn't worth it for the small amount of money I get 
 from 
 selling.

 On Thursday, March 31, 2022 at 6:29:12 PM UTC-4 threeneurons wrote:

> eBay has been doing this now, for about a year and a half. I've had no 
> problems, so far. Initially, I didn't understand why they did this, only 
> a 
> few years after selling off Paypal. So It seemed kinda stupid. But I 
> think 
> it has to do with some legal changes both in the US and in Europe. In the 
> US, all online transactions need to include the sales tax of the buyer's 
> state. In Europe, they want the VAT 

Re: [neonixie-l] Re: Sylvania Florotron Display. 8894

[ZY]

Do the colors match between the tubes and the spiral tubes? I remember last 
I tried the colors were kind of off, but I forget which spiral I used and 
perhaps my voltages weren't optimal.

On Tuesday, 8 February 2022 at 18:46:23 UTC-5 M1 wrote:

> Understood.  Agreed.  I need to relax too.
>
>  
>
> Just to clarify, I was talking about the Spiral and not exact 
> information.  I guess in this group, I should be exact.  
>
>  
>
>  
>
> Michail Wilson
>
> 206-920-6312 <(206)%20920-6312>
>
>  
>
> *From:* neoni...@googlegroups.com  *On Behalf 
> Of *Audrey
> *Sent:* Tuesday, February 8, 2022 3:26 PM
> *To:* neoni...@googlegroups.com
> *Subject:* Re: [neonixie-l] Re: Sylvania Florotron Display. 8894
>
>  
>
> Woahhh calm down... I was just trying to make it clear for anyone reading 
> that they arent the same part exactly- to eliminate any possible future 
> confusion.
>
> I dont have all 3 on hand so I cant give you complete comparisons but 
> 6977s are thinner and longer than iv-15s...
>
>  
>
> On Tue, Feb 8, 2022, 6:22 PM Michail Wilson  wrote:
>
> I’m sorry.
>
>  
>
> You are absolutely right, but it would be nice if you could elaborate 
> instead of just saying they are not.
>
>  
>
> Other than being from different manufactures and having different part 
> numbers and many other things, like glass, exact size, etc, they are 100% 
> different.
>
>  
>
> If you relax a little, my point was that all three are Spiral’s.   My 
> comment was regarding the appearance of a spiral and not the exact 
> similarities and differences.
>
>  
>
> Michail 
>
>  
>
> *From:* neoni...@googlegroups.com  *On Behalf 
> Of *Audrey
> *Sent:* Tuesday, February 8, 2022 3:12 PM
> *To:* neoni...@googlegroups.com
> *Subject:* Re: [neonixie-l] Re: Sylvania Florotron Display. 8894
>
>  
>
> Theyre similar but I know that the 6977 and iv-15 are not identical
>
>  
>
> On Tue, Feb 8, 2022, 6:11 PM Michail Wilson  wrote:
>
> I was referring to your clock.  Love it.
>
>  
>
> I was just trying to say the spiral tubes are great – All three are the 
> same thing -- IV-15, DM160, 6977
>
>  
>
>  
>
> Michail Wilson
>
> 206-920-6312 <(206)%20920-6312>
>
>  
>
> *From:* neoni...@googlegroups.com  *On Behalf 
> Of *Paul Andrews
> *Sent:* Tuesday, February 8, 2022 6:42 AM
> *To:* neonixie-l 
> *Subject:* Re: [neonixie-l] Re: Sylvania Florotron Display. 8894
>
>  
>
> If you're referring to my clock, they are IV-15.
>
> On Monday, February 7, 2022 at 6:06:28 PM UTC-5 M1 wrote:
>
> A clock was posted with the colons.  Love the spiral.
>
>  
>
> I found them to be:
>
> IV-15 or DM160 or 6977
>
>  
>
> I bought a bunch thinking they were a lot bigger and was disappointed with 
> the size, but still like them.
>
>  
>
> Was surprised when I just checked to see their prices.   Damn.
>
>  
>
> Michail Wilson
>
> 206-920-6312 <(206)%20920-6312>
>
>  
>
> *From:* neoni...@googlegroups.com  *On Behalf 
> Of *Audrey
> *Sent:* Saturday, February 5, 2022 9:14 AM
> *To:* neoni...@googlegroups.com
> *Subject:* Re: [neonixie-l] Re: Sylvania Florotron Display. 8894
>
>  
>
> Nice little collection bill :), wonderful tubes either way of course
>
>  
>
> On Sat, Feb 5, 2022, 8:34 AM Bill Notfaded  wrote:
>
> I love these tube with and without mica.  When I first saw them without 
> mica I had to have some because they are unlike any other VFD I've ever 
> seen!
>
> Bill
>
> On Friday, February 4, 2022 at 10:16:44 AM UTC-7 tntm...@gmail.com wrote:
>
> Hi Bill, the DT-1704A, DT-1704B, DT-1705A and DT-1705B Digivac tubes 
> actually had true floating segments without mica sheets, the later DT-1704C 
> and DT-1705C tubes implemented the mics sheet, probably a good change for 
> reliability.
>
>  
>
> On Fri, Feb 4, 2022, 5:44 AM Bill Notfaded  wrote:
>
> Awesome thanks for the datasheet!  It looked to me similar to the other 
> what I call floating VFD on mica type tubes like a handful of others.
>
>  
>
> Bill
>
> On Thursday, February 3, 2022 at 7:01:53 PM UTC-7 charles wrote:
>
> According to the original data sheet the 8894 is more or less standard 
> 7 segment VFD. clipping from the TCA Data Cache. 
>
>
> -- 
> Charles MacDonald VA3CPY Stittsville Ontario 
> cm...@zeusprune.ca Just Beyond the Fringe 
> No Microsoft Products were used in sending this e-mail.
>
> -- 
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> https://groups.google.com/d/msgid/neonixie-l/0025d7d5-97bd-41b0-aaac-e5ce308f9b1an%40googlegroups.com
>  
> 
> .
>
> -- 
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Re: [neonixie-l] Where to get PCBs from, some companies blocked by PayPal and credit card issuers......

[ZY]

I also use OSHPark but only because for small pcbs they have they are the 
cheapest ENIG option. I know it probably makes no difference, but the after 
dark PCBs with ENIG do look nice.

If another supplier can do the same look but cheaper I'd have no issue with 
swapping, since for anything larger than a tiny PCB the oshpark prices get 
high real quick.

I have had a couple boards from them in the past where there were some 
manufacturing defects like connecting traces. They give you 3 per order so 
it's usually fine, but it did lose me a bit of time and wasted components 
trying to debug.

Also I recall in the past when they were BatchPCB they would clean the 
board edges. They don't do that anymore, meaning I have to individually 
dremel and clean the breaking points of each pcb, which is an annoyance to 
do safely if you have a bunch of small pcbs and don't want to breath in pcb 
dust (it's also itchy if you get it on your hands).

On Friday, 24 December 2021 at 10:28:54 UTC-5 Toby Thain wrote:

> On 2021-12-24 9:52 a.m., martin martin wrote:
> > Here's where I go:
> > http://mpi-pcb.com/contact-mpi.php 
> > 
> > Local USA and very good!
> > 
> > 
>
> Surprised nobody has mentioned OSHpark yet (on google results they are 
> buried under four ads for other companies...)
>
> https://oshpark.com/
>
> They take native KiCAD files. Just a satisfied customer.
>
>
> --Toby
>

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[neonixie-l] Re: 4-digit IN-18 clock project

[ZY]

Oh nice, I've been using the same chip but I wanted to double check if 
there wasn't some other solution people were using.

I went with the SiSB46DN suggested by the datasheet and I've been fine with 
protection even for 3.3V with a lower voltage bound of 3V.

I've also tested a circuit for 0.6-1.5V for filaments by powering the IC at 
a higher voltage but applying the lower V-filament to the transistor, and 
that also works.

On Monday, 8 November 2021 at 01:29:04 UTC-5 newxito wrote:

> This is the protection circuit I use, taken from the LTC4365 datasheet. I 
> used the formulas to calculate the resistors and the LTspice simulation 
> confirmed the values. The circuit works, kind of, shuts down under 4V and 
> over 6V. But when starting with 5V I only get around 4.2 output voltage, 
> that’s wrong. Probably some kind of oscillation…
> I use the same circuit with other resistor values for 12V and it works 
> perfectly all the time.
>
>
> ZY schrieb am Montag, 8. November 2021 um 01:59:34 UTC+1:
>
>> What is your method of input protection?
>>
>> On Sunday, 7 November 2021 at 17:14:52 UTC-5 newxito wrote:
>>
>>> Today I built the clock. There is an error on the board, the DataIn pin 
>>> of the LED array is connected to the wrong side of the level shifter, but 
>>> it seems to work fine with 3.3V. I also had problems with the input 
>>> protection (over, under and reverse voltage). I always used the circuit 
>>> with 12V but this boards uses 5V, probably the monitoring window is too 
>>> small. Anyway, removing some components and a big blob of solder, solved 
>>> the problem :-)  
>>> I fill fix the design errors on Rev2… time to start making the case…
>>>
>>>

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[neonixie-l] Re: 4-digit IN-18 clock project

[ZY]

What is your method of input protection?

On Sunday, 7 November 2021 at 17:14:52 UTC-5 newxito wrote:

> Today I built the clock. There is an error on the board, the DataIn pin of 
> the LED array is connected to the wrong side of the level shifter, but it 
> seems to work fine with 3.3V. I also had problems with the input protection 
> (over, under and reverse voltage). I always used the circuit with 12V but 
> this boards uses 5V, probably the monitoring window is too small. Anyway, 
> removing some components and a big blob of solder, solved the problem :-)  
> I fill fix the design errors on Rev2… time to start making the case…
>
>

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Re: [neonixie-l] Re: CRISTAL + CAPACITOR = TIME DELAY HELP

[ZY]

If you're going with SMD components, you can also try using a SMD crystal 
to simplify the build process some more. I used this one for example 
(although currently out of stock, but there are probably similar ones)
https://www.digikey.com/en/products/detail/fox-electronics/FK135EIHM0-032768-T3/1024594

Also for future reference, sometimes it's actually the RTC that is faulty. 
I order a lot of components from aliexpress and have had no issues with 
going cheap, except in the case with RTCs. With cheap RTCs they are 
sometimes the ones that failed a self test off the production line and 
they'd be way off on time. I have a testing rig set up to make the RTC 
output a test frequency square wave that I can measure with a multimeter 
before I solder them.

On Monday, 19 July 2021 at 08:27:43 UTC-4 MrThe50sanchez wrote:

> Hello! 
>
> It looks like I was in a Mistake with the datasheet of the crystal, 
> thinking that the 6.0 to 12.5 pf capacitors would be perfect for the time 
> running perfect, But with this configuration, I have like 2 mins of delay 
> in 24H. 
>
> I really appreciate the help, Just took a quick look and you are right, 
> 22-27Pf and 220K ohm seems that is going to fix the delay I have. 
>
> I will have a good reading of the links you added, will try, and will let 
> you know. 
>
> Thanks a lot! 
>
> El lun, 19 jul 2021 a las 1:24, gregebert () 
> escribió:
>
>> It is gaining time, or losing time ?
>>
>> If it's losing time, could it be caused by execution delays in your 
>> software ? I've seen some really bizarre things happening with my Raspberry 
>> Pi based clocks because of the chaotic behavior of Linux, and I have even 
>> seen metastability-related failures due to the way I had software scanning 
>> hardware for asynchronous events. They are fixable, but they definitely 
>> challenge your debugging skills.
>>
>> BTW, the last time I saw such a thing was *yesterday*I'm testing my 
>> RZ568m tubes for a new clock, and saw my time jump by 2 seconds, instead of 
>> the usual 1 second, because of the way in which I update the displayed 
>> time. These are often subtle bugs you dont catch while typing-in your code.
>>
>> On Sunday, July 18, 2021 at 12:19:21 PM UTC-7 Dekatron42 wrote:
>>
>>> The capacitance you cite from the datasheet is not the recommended 
>>> capacitance for the external capacitors, it is the load capacitance of the 
>>> crystal - you must check your ordering document to see which crystal you 
>>> got unless you can read the information on the crystal itself if it is 
>>> laser printed there. The load capacitance can then be used to calculate 
>>> what capacitance value you need for the two other capacitors - do a quick 
>>> test with two 22pF or 27pF capacitors if you have the crystal with CL = 
>>> 12.5pF - twice the load capacitance from the formula in the application 
>>> note: http://ww1.microchip.com/downloads/en/appnotes/91097a.pdf is 
>>> usually a good start, so if you have a lower CL value use twice that for 
>>> tests.
>>>
>>> Neither is the series resistance in the datasheet the value you need for 
>>> the external resistor, it is the internal resistance of the crystal itself. 
>>> You should use the value in the application note to start with, 220k - it 
>>> might be that you have damaged the small crystal by over driving it if you 
>>> used a lower value, it is explained in the application note why you need to 
>>> protect the crystal from over driving. You can read some on series 
>>> resistance and crystal selection here: 
>>> https://www.maximintegrated.com/en/design/technical-documents/tutorials/7/726.html
>>>  
>>> . The datasheets and product documentation found on the manufacturer 
>>> website: 
>>> https://www.microcrystal.com/en/products/khz-quartz-crystals/ms3v-t1r/ 
>>> and 
>>> https://www.microcrystal.com/en/products/khz-quartz-crystals/ms1v-t1k/ 
>>> do contain the equivalent circuit for the crystal similar to the one above.
>>>
>>> So try with twice the load capacitance for both capacitors and use the 
>>> recommended 220k resistor as in the application note and see how it behaves 
>>> - also use the pins recommended in the application note, ie CLKIN & CLKOUT.
>>>
>>> /Martin
>>> On Sunday, 18 July 2021 at 20:53:32 UTC+2 MrThe50sanchez wrote:
>>>
 Hello Again group! 


 I've been testing this for a while, and I still have some delay 
 minutes. This is the PCB design I'm using and components.

 *Components: *
 ·PIC16F1936 
 ·CRYSTAL MS3V-T1R CRYSTAL 32.768 Khz. 
 ·Capacitors ( used 6.0 ; 7.0 ; 9.0 & 12.5) pF as datasheet from crystal 
 recommend.
 ·Resistor value between 50/65 K ohm. 

 *PCB Design: *

 This design is done following the document you guys added called:  
 Microship TB097 which give's good instructions on how install Crystals to 
 our pics. 


 Guys, My head is gonna explote because I don't find the problem that is 
 making minutes 

[neonixie-l] Re: Multiplexing tubes with 1 x K155ID1 vs 2 x K155ID1?

[ZY]

Do you use PWM at all for dimming, or do you control the tube voltage? I do 
find that my IN-18s sing a bit at certain PWM settings so I've wondered too 
if that would have a negative effect.

In terms of motion sensing, I did add that feature to a recent build I did 
but I was curious if the thermal cycling from tubes turning on/off would be 
more harmful than just keeping them constantly on. I mean the tubes do get 
a tiny bit more warm than ambient when on.

On Thursday, 15 July 2021 at 11:47:49 UTC-4 gregebert wrote:

> From what I've read, the peak current is what leads to tube wearout, and 
> the effect is exponential: double the current, and the lifetime will be 
> less than half the normal expectancy. So when a tube is pulsed, such as 
> with multiplexing, the perceived brightness will always be lower compared 
> to static operation and the only way to compensate for that is higher 
> current. If you have a single tube you can control with a microcontroller, 
> you can easily emulate how it will appear when multiplexed.
>
> I have limited data on perceived brightness vs current. When I was taking 
> extensive data on my b7971 and RZ568m tubes, I found that once you get to 
> about 75% of normal operating current, further increases in current dont 
> give as noticeable increase in brightness. Of course, this is subjective 
> because I didn't use a photometer to measure the optical output. I never 
> attempted to get PWM data, because I only use direct-drive in my designs.
>
> Multiplexing is tricky because you have to tradeoff between peak current, 
> duty-cycle, frequency, dead-time (to minimize ghosting), ambient lighting. 
> Ultimately, it amounts to a tradeoff between brightness and tube life. Some 
> folks have said you can actually hear tubes making noise when multiplexed 
> or PWM-dimmed, and I've often wondered if the mechanical stresses involved 
> in producing the noise affect the tube's life.
>
> The best way to prolong tube life is to make sure you never exceed the 
> maximum current rating in the datasheet. Better manufacturers will provide 
> both min and max values, and if they dont provide a typical value, then use 
> the average of min & max to select the operating current.
>
> Next, use a cheap passive- infrared motion sensor (PIR) to shut off the 
> display when nobody is around, or when you are asleep. This will greatly 
> extend the life of your tubes.
>
> Unless the tube is specifically designed for multiplexed operation, such 
> as multi-digit displays that have shared cathodes, your best option is to 
> use direct-drive to maximize lifetime. Electronic parts are inexpensive and 
> readily available; nixie tubes are expensive and the finite supply is 
> rapidly shrinking.
>
> On Thursday, July 15, 2021 at 1:33:49 AM UTC-7 ZY wrote:
>
>>
>> Ooops, sorry Gregebert, I'm not experienced with google groups and I 
>> didn't know the difference between reply to group vs. reply to author.
>>
>> I'm going to repeat my question so it's group visible:
>>
>> Basically I was wondering for multiplexed vs direct drive, if given the 
>> same voltage and current limiting resistor, would the max brightness of the 
>> multiplexed tubes be basically like the direct drive tubes operating at 1/6 
>> pwm ratio? It might not be 1/6 brightness due to non-linearity, and maybe 
>> additional effects based on frequency of the pwm or multiplexing. But in 
>> that case, there shouldn't be any additional wear on the tubes right? The 
>> wear only comes from if you want to increase the multiplexed tube's 
>> brightness even more, to match a direct drive with a higher pwm ratio?
>>
>> I was wondering because I thought about going multiplexed to save on 
>> board space and soldering time.
>> On Tuesday, 13 July 2021 at 05:26:50 UTC-4 andybiker wrote:
>>
>>> It's also worth mentioning that with a multiplexed design it's easy to 
>>> dim the tubes for a dark room and obviously extend the life.
>>> I have a bedroom arduino-based clock that has 4x NL5780 multiplexed.
>>> The brightness auto-dims so that it's nice at night (and at a level that 
>>> would be invisible during the day) and then is bright during the day. 
>>>
>>> On Tuesday, July 13, 2021 at 6:28:29 AM UTC+1 owen.cra...@gmail.com 
>>> wrote:
>>>
>>>> Makes perfect sense. Thank you for the explanation. Think I'll be going 
>>>> down the direct drive route for my designs.
>>>>
>>>> On Tuesday, 13 July 2021 at 14:43:30 UTC+10 gregebert wrote:
>>>>
>>>>> If you use 1 decoder for 6 tubes, the duty-cycle is 1/6 and it will 
>>>>> require more current to get 

[neonixie-l] Re: Multiplexing tubes with 1 x K155ID1 vs 2 x K155ID1?

[ZY]

Ooops, sorry Gregebert, I'm not experienced with google groups and I didn't 
know the difference between reply to group vs. reply to author.

I'm going to repeat my question so it's group visible:

Basically I was wondering for multiplexed vs direct drive, if given the 
same voltage and current limiting resistor, would the max brightness of the 
multiplexed tubes be basically like the direct drive tubes operating at 1/6 
pwm ratio? It might not be 1/6 brightness due to non-linearity, and maybe 
additional effects based on frequency of the pwm or multiplexing. But in 
that case, there shouldn't be any additional wear on the tubes right? The 
wear only comes from if you want to increase the multiplexed tube's 
brightness even more, to match a direct drive with a higher pwm ratio?

I was wondering because I thought about going multiplexed to save on board 
space and soldering time.
On Tuesday, 13 July 2021 at 05:26:50 UTC-4 andybiker wrote:

> It's also worth mentioning that with a multiplexed design it's easy to dim 
> the tubes for a dark room and obviously extend the life.
> I have a bedroom arduino-based clock that has 4x NL5780 multiplexed.
> The brightness auto-dims so that it's nice at night (and at a level that 
> would be invisible during the day) and then is bright during the day. 
>
> On Tuesday, July 13, 2021 at 6:28:29 AM UTC+1 owen.cra...@gmail.com wrote:
>
>> Makes perfect sense. Thank you for the explanation. Think I'll be going 
>> down the direct drive route for my designs.
>>
>> On Tuesday, 13 July 2021 at 14:43:30 UTC+10 gregebert wrote:
>>
>>> If you use 1 decoder for 6 tubes, the duty-cycle is 1/6 and it will 
>>> require more current to get the same brightness as a tube with a higher 
>>> duty-cycle. So, if you use 2 decoders, the duty-cycle is 1/3 and the peak 
>>> current will be less vs 1/6 duty cycle.
>>>
>>> Personally, I never multiplex tubes because it requires more current per 
>>> tube, and the wearout mechanism for tubes (sputtering), increases 
>>> exponentially with current. In my opinion, IC's are cheap and readily 
>>> available whereas nixies are much more expensive and getting harder to 
>>> find, so it makes the most sense to drive the tube as gently as possible, 
>>> ie direct-drive, to prolong their life.
>>>
>>> On Monday, July 12, 2021 at 8:00:07 PM UTC-7 owen.cra...@gmail.com 
>>> wrote:
>>>
 A little but of a noob question, though looking around at different 
 multiplex clock designs, I see that some setups opt for 2 x K155ID1and 
 others only have 1.

 A classic example with 2 x drivers would be: 
 http://www.arduinix.com/Main/Gallery.htm

 Then I find others with just 1 x drivers: 
 https://www.instructables.com/simple-user-adjustable-DIY-Nixie-Clock/
 And: https://www.nixieclock.biz/StoreClassicRev5.html

 Why is this the case? I have also seen similar sketch codes to drive 
 both single and double drivers, so I am wondering what the decision 
 process 
 around this is and if it's even necessary to have 2 drivers to begin with?

>>>

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Re: [neonixie-l] Re: What is a fair price for IN-14's nowadays?

[ZY]

I might have to bite the bullet and shell out for a set of IN-14s and a 
couple IN-18s to make another set of clocks. 

What's the next tube down the line in terms of similar digit size and 
lifespan? I would assume the IN-12 is a cheaper alternative to IN-14 if you 
can deal with the top-down view?

Soon the IN-18 price will reach the Millclock ZIN-18 price, making the 
newer nixies a better buy. I'm not sure what the ZIN-18's rated life is 
though, and I guess IN-18s will continue to rise above that due to the 
vintage/rare appeal.

On Thursday, 1 July 2021 at 01:18:20 UTC-4 Richard Scales wrote:

> Nick, if you get there, same message to 2010 Richard please
>
> In recent years I bought a box of 25 x IN-18 for £725 delivered to the UK, 
> that was a bit of a stretch for me at the time.
>
> If I knew then what I know now - I would have stretched a little further I 
> think.
>
> - Richard
>
>
> On Wednesday, 30 June 2021 at 21:17:11 UTC+1 tntm...@gmail.com wrote:
>
>> I've heard end-view and side-view in tube datasheets, I'm curious what 
>> you got those boxes of IN-18s for
>>
>> On Wed, Jun 30, 2021, 4:14 PM Bill Notfaded  wrote:
>>
>>> Nick-
>>>
>>> I did a little bit of that... but not nearly enough.  I bought a sealed 
>>> box of OG-4 and A-101 dekatrons... just because I could.  I also bought 
>>> some full boxes of IN-12's.  A few years ago I bought some full boxes of 
>>> IN-18's but any full boxes now people want ridiculous money for.  I suppose 
>>> for us it's a little harder when you know what you paid not that many years 
>>> ago.  I think supply is finally drying up... reaching even the eastern 
>>> block sellers that are scraping bottom of the barrel now.  This should be 
>>> good news for new Nixie manufacturers!  I can't wait to build a big round 
>>> top facing Dalibor tube clock!!!
>>>
>>> That brings up something else... what is the correct terminology for 
>>> tubes/type/view?  I always think of IN-18 style tubes as side view, and 
>>> round B-8091 style tubes at top view.
>>>
>>> Bill
>>>
>>> On Wednesday, June 30, 2021 at 12:20:45 PM UTC-7 Pramanicin wrote:
>>>
>>>> If people keep paying these prices, then sellers will keep charging 
>>>> them...clearly someone is paying these amounts (which kind of blows my 
>>>> mind), but such is supply and demand.
>>>>
>>>> As usual, I'm still kicking myself that I can't talk to circa 2010 Nick 
>>>> and say "hey, you may want to load up on some of those boxes of new IN-14 
>>>> at $100."
>>>>
>>>> :)
>>>>
>>>> On Wed, Jun 30, 2021 at 10:54 AM Bill Notfaded  
>>>> wrote:
>>>>
>>>>> I'm afraid it's supply and demand and the supply must be getting low...
>>>>>
>>>>> Bill
>>>>>
>>>>> On Wednesday, June 30, 2021 at 12:04:16 AM UTC-7 ZY wrote:
>>>>>
>>>>>> I bought maybe 30-40 IN-14s a while back when they were going for a 
>>>>>> used price of $2-2.5 per tube after including shipping. 
>>>>>>
>>>>>> I finally used up most of my stash building clocks for family and 
>>>>>> friends and I wanted to get a few more, but wow the prices have 
>>>>>> ballooned. 
>>>>>> The exact ebay listing I used for a lot of 6 a few years ago went from 
>>>>>> $20 
>>>>>> to $100 from the same seller!
>>>>>>
>>>>>> I haven't been in the buying business often enough to know if this is 
>>>>>> a price wave that will eventually subside, or because of rising 
>>>>>> popularity 
>>>>>> and limited stock the prices will only go up.
>>>>>>
>>>>>> I'm wondering what should be a fair price for IN-14s now? I'm seeing 
>>>>>> maybe $15 per used tube? Am I just looking at the wrong places or is 
>>>>>> eBay 
>>>>>> still an ok place?
>>>>>>
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>>>>> https://groups.google.com/d/msgid/neonixie-l/3e5a3dc4-262c-4230-a112

[neonixie-l] Re: My IN-18 clock project

[ZY]

Thanks! I got the PCBs from oshpark which do a black PCB with clear 
soldermask service that looks really nice. The modularness also stems from 
that since they give 3 copies of your design per order, so I can save a bit 
of money if I don't intend to build 3 clocks. It does increase the costs of 
connectors and build time significantly, and crimping those wires was 
probably the most annoying part of the build.

In my original IN-14 design I actually intended to print a transparent case 
so I could see the internals, but I couldn't really get it to be 
see-through enough without the shell walls being extremely thin.
On Wednesday, 30 June 2021 at 13:59:56 UTC-4 Bill Notfaded wrote:

> It looks like you used a modular pcb design for it.  Some of the hardware 
> looks so nice it's almost bordering on BadNixie aesthetics... almost a 
> shame to hide really nice looking hardware pieces.  Part of thing I love 
> about my Mod-Six and my Black Emerald are the way the hardware/pcb/case all 
> are on display in such a professional hand crafted kind of way!
>
> Bill
>
> On Tuesday, June 29, 2021 at 11:56:25 PM UTC-7 ZY wrote:
>
>> Thanks! The case is 3D printed, I used some sparkly grey filament from 
>> proto-pasta. I would love to CNC an aluminum one but the cost would be a 
>> bit out of my league.
>>
>> On Wednesday, 30 June 2021 at 02:30:32 UTC-4 newxito wrote:
>>
>>> Well done! I like the case and the nice knob on the back. Is the case 3D 
>>> printed?
>>>
>>>

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[neonixie-l] What is a fair price for IN-14's nowadays?

[ZY]

I bought maybe 30-40 IN-14s a while back when they were going for a used 
price of $2-2.5 per tube after including shipping. 

I finally used up most of my stash building clocks for family and friends 
and I wanted to get a few more, but wow the prices have ballooned. The 
exact ebay listing I used for a lot of 6 a few years ago went from $20 to 
$100 from the same seller!

I haven't been in the buying business often enough to know if this is a 
price wave that will eventually subside, or because of rising popularity 
and limited stock the prices will only go up.

I'm wondering what should be a fair price for IN-14s now? I'm seeing maybe 
$15 per used tube? Am I just looking at the wrong places or is eBay still 
an ok place?

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[neonixie-l] Re: My IN-18 clock project

[ZY]

Thanks! The case is 3D printed, I used some sparkly grey filament from 
proto-pasta. I would love to CNC an aluminum one but the cost would be a 
bit out of my league.

On Wednesday, 30 June 2021 at 02:30:32 UTC-4 newxito wrote:

> Well done! I like the case and the nice knob on the back. Is the case 3D 
> printed?
>
>

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[neonixie-l] Re: Vintage LED display, VQB76. What's the relationship between RFT and WF?

[ZY]

Thanks for the info everyone. I'm going to try to set up a small clock out 
of these.

On Tuesday, 19 January 2021 at 16:54:27 UTC-5 Jon wrote:

> We're talking about the old East Germany here, the DDR. As I understand it 
> RFT was a large state-owned enterprise which had a number of operating 
> subsidiaries amongst which production responsibility was divided. WF was 
> one of these, based in Berlin at the Oberspreewerk, at least during the 
> 1960s when it made nixies and dekatrons amongst other things. If you search 
> German Wikipedia there's quite some background covering origins and 
> evolution of the factory - Google Translate will help you out with the 
> language if needed (which needless to say it was for me!).
>
> Jon.
>
>
> On Tuesday, January 19, 2021 at 6:26:33 PM UTC alex nolan wrote:
>
>> No expert by any means, but according to 
>> https://frank.pocnet.net/brand.html WF is listed as "RFT Werk für 
>> Fernsehelektronik". It seems to be a subsidiary or branch of RFT of some 
>> kind.
>>
>> On Tuesday, January 19, 2021 at 2:55:35 AM UTC-5 ZY wrote:
>>
>>> Apologies for not being a nixie tube here, but it's a vintage display so 
>>> hopefully it fits the theme.
>>>
>>> I have some old VQB76 LED modules with the logo WF. I see for tubes WF 
>>> is associated with RFT. Is WF a brand name, or a separate company? And what 
>>> does it stand for?
>>>
>>>

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Re: [neonixie-l] Re: Anyone recognize these nixie tubes?

[ZY]

I saw that the seller is also selling newly manufactured nixies with part 
number MX-57X. Perhaps these two are not really "vintage" nixies but are 
just prototype verrsions of the MX-57X tubes? They look very similar in 
design. 

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[neonixie-l] Re: VFD filament resistance when hot/cold?

[ZY]

The chip I'm using is TPS54328, which has an adjustable soft start. I'm 
still building my supply though, so I haven't actually tested it in action 
yet to see if the soft start actually limits the inrush in any way.

On Thursday, 16 July 2020 13:56:47 UTC-4, Paul Andrews wrote:
>
> What power supply are you using? I seem to collect power supply design 
> almost as much as Nixie tubes.
>
> On Wednesday, July 15, 2020 at 11:20:23 PM UTC-4, ZY wrote:
>>
>> For my VFD filaments, I've settled on using a power supply module with a 
>> configurable soft-start time. I've set it to something huge, like 10 
>> seconds, to try to limit the inrush current. 
>>
>

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[neonixie-l] Re: VFD filament resistance when hot/cold?

[ZY]

For my VFD filaments, I've settled on using a power supply module with a 
configurable soft-start time. I've set it to something huge, like 10 
seconds, to try to limit the inrush current. 

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[neonixie-l] Re: Divergent Nixie clock designs

[ZY]

You can also have decontrons do the counting:
https://www.youtube.com/watch?v=4bl5kSr8C3Q

I'm guessing some more parts can be replaced with tubes by replacing the 
rectifier with a tube rectifier.

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[neonixie-l] Re: Divergent Nixie clock designs

[ZY]

You can also have decatrons do the counting:
https://www.youtube.com/watch?v=4bl5kSr8C3Q

I'm guessing some more parts can be replaced with tubes by replacing the 
rectifier with a tube rectifier.

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[neonixie-l] Corrosion vs. air humidity

[ZY]

Hello. I live near the coast and my air humidity is pretty high, usually 
it's around or above 50% on warmer days and maybe even higher if it rains. 
While I store my nixies in containers with a few silica packets, the nixies 
that are built into clocks are exposed to the humidity.

I'm wondering if such humidity has any noticeable impact on nixie lifespan 
in terms of rusting at the glass-metal interface?

Would it be a good idea to apply a bit of conformal coat over the 
glass-metal interface, or would the risk of the conformal coat chemically 
attacking the area over time be more than what humidity can do? The coating 
I usually use for PCBs is MG Chemicals silicone modified conformal coating. 

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Re: [neonixie-l] VFD Filament Current

[ZY]

I took a look at the LM9022 datasheet and it's drive method seems similar 
to my H-bridge + oscillator. I've built and tested it but haven't ran it 
long term with my ILC1-1/7s. I'm still looking for anything to improve on 
before I finalize the driver for my clock.

[image: 3.PNG]

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[neonixie-l] Re: Input voltage protection

[ZY]

Would you be able to elaborate on how the transformer prevents the inrush 
current? I'm a bit new to using transformers for anything. Also do you have 
a part number suggestion?

Currently for my ILC1-1/7 VFD project, I'm using a SiP2100 hbridge to 
generate my filament voltages that inverts itself at some frequency I 
selected. I've current limited the hbridge's Vin using a lm317, and fused 
the hbridge output. I was hoping the lm317 in current mode would prevent 
the inrush.

I was also wondering if adding a center tapped transformer to my hbridge 
output would help anything. I don't think with my setup I would have any 
brightness slant even without the transformer as the 5V and 0V are flipping 
as opposed to having one side of the filament constantly grounded. Also I'm 
wondering if I need to reduce my 5V value since the filament is rated for 
5V, but I'm not sure if that's under a sign wave. 

Anyway for the original question, I'm also interested in the LTC4365 IC 
after looking at the datasheet. I built a little circuit that I'll use to 
test it out:

[image: 1.PNG]

[image: 2.PNG]

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Re: [neonixie-l] Input voltage protection

[ZY]

Do you have a suggestion on an A/D IC? Or are you using one from the uC 
directly? I'm looking to sprinkle some A/D everywhere for my nixie and non 
nixie projects just for fun.
On Tuesday, 10 September 2019 15:51:18 UTC-4, gregebert wrote:
>
> My current clock went a bit overboard with self-checking; I have A/D 
> converters on all supplies and software periodically monitors them for 
> out-of-tolerance, and will shut-down the HV if that happens
>
 


Also on a similar but separate note, anyone have a suggestion on how to 
protect the filament (~1V) for VFD tubes? I'm always scared my buck 
converter will fail and pass Vin through the filament of my harder to fine 
VFDs.

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Re: [neonixie-l] Re: IN-28's in real life...

[ZY]

What is your plan for powering this display? I ask because I also have 4 
modules that I'm trying to get to work.

As far as I can see, at 13mA per tube, lighting all 23 digits requires 
0.3A, which at 175V is like 52 watts? And that's just one of the digits.

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[neonixie-l] Re: Numerical nixies similar to Dolamn LL-555-558 for letters I and O

[ZY]

Thanks! I did eventually also stumble on those two but I wanted to be sure 
since I couldn't find their datasheets. I did snatch a few 513As so 
hopefully it will work out.

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[neonixie-l] Numerical nixies similar to Dolamn LL-555-558 for letters I and O

[ZY]

Hello,

I'm trying to spell out a word with non-segmented nixie tubes, and it seems 
the Dolam LL-555 to 558 series are my best bet for something available on 
ebay.

However I notice that the tubes do not include I and O, which I assume 
would be done by a numerical 0-9 tube.

I need a suggestion as to which tube is the numerical version of the 
series, or if there is none, which tube would look similar. As in something 
of the same size/shape/overall look. Preferably also available on ebay.

I looked at the IN-1 but it seems to be attached to a large bracket that 
the Dolam tubes do not have.

Thanks!

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[neonixie-l] Re: OT: Lateral thinking: Cheap SMT reflow oven...

[ZY]

Almost all my projects are now SMT, mainly because I feel it saves so much 
time and money (smaller board size) compared to through hole components. 
It's way faster for me to place the parts than to manually solder each 
through hole component.

I currently use mostly 0603 parts and I recommend oshstencils for cheap 
plastic stencils. Whenever I send parts to oshpark I simultaneously do an 
oshstencil order.

I use the hot plate method to do my soldering. It's not entirely 
recommended because a hot plate gets pretty variable in temps, but if you 
just sit beside it for a few minutes and take the board off when you start 
seeing the solder melt it should be fine. I mark the spot on my dial where 
the temperatures are usually the best for me. However I'm currently working 
on a project to convert an old toaster oven to do the reflow automatically. 
I'm trying to get the temperature display to be nixie tube based.

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[neonixie-l] A finished in-14 nixie clock from a beginner

[ZY]

I just managed to finish my first complete nixie clock. I'm not too good 
with woodworking/metalworking so I 3D printed a case instead:

front: http://i.imgur.com/tBOOyoU.jpg

back: http://i.imgur.com/dEGT2B4.jpg

bottom: http://i.imgur.com/AdROsfL.jpg

Insides during test (no standoffs and some parts not soldered). I didn't 
drill a hole for the colon digit in the final build:
http://i.imgur.com/7KP2a1U.jpg

I got some help from you guys a while back in debugging some issues with my 
boost converter. Thanks for the assistance!

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Re: [neonixie-l] Need help with a 230IK1 IC (nixie driver)

[ZY]

Thanks everyone for the help! I can start some tests with this info. I'm 
going to order a couple 1.25mm pitch FPC connectors from digikey first so I 
can connect to the IC without soldering to it.

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[neonixie-l] Need help with a 230IK1 IC (nixie driver)

[ZY]

I got my hands on a few 230IK1 chips and I want to use them for a project 
as I think they look a bit cooler than the usual K155ID1.

However, I don't know any Russian so reading the datasheets are a bit 
difficult. So far, I found this website:

http://www.155la3.ru/k230.htm

Halfway down the page, it shows off the 230IK1 IC with a datasheet:

http://www.155la3.ru/datafiles/230ik1.pdf

However it doesn't give much information on which pins provide power. I 
think K230IK1 is equivalent except for some temperature specs, and I found 
this datasheet:

http://www.quartz1.com/price/PIC/411N0944515.pdf

Would someone be able to translate for me the pinouts for K230IK1?

I'm assuming pins 49 and 50 are 5V, 24 and 25 are GND, but I want to be 
sure.

Thanks a bunch!

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[neonixie-l] Re: Constant current source design

[ZY]

I just want to add that for the low current scenario, the voltage should be 
consumed by the nixie. The voltage across the LM317 will continue to drop 
with reducing current, down to about 0.75V at 0.2mA under a test I did. 
Only in overcurrent would there be an issue, as the voltage across it will 
increase beyond it's limit. 

On Monday, 27 March 2017 02:36:01 UTC-4, Tomasz Kowalczyk wrote:
>
> It all depends on R11 and desired current. Most nixies have a minimum 
> voltage drop of around 120V (although they will maintain 130 for most of 
> the time, they will just continue to work with lower voltage), so if 
> voltage drop on R11 is more than (supply voltage - 120V - 
> LM317_max_voltage), then it is safe - the only case where the nixie doesn't 
> have that voltage drop is when it is internally shorted.
> In this schematic, assuming that U15 is fully open, so voltage at R11 left 
> side is just about 180V, everything will be okay - the LM317 is set for 
> 8mA, so voltage drop over R11 would be around 34V and everythin would be 
> safe. The problem is that if current is significantly lower that (nixie is 
> heavily poisoned), then stuff can get bad: as far as I understand, R11 
> voltage drop has to be lower (Ohms law), so the voltage across LM317 will 
> get higher, I think - it has to drop somewhere.
> Long story short, you are right - LM317 can fail in non-standard 
> situation. That's why I would go for a two-transistor design using MMBTA42 
> (or MPSA42), which will withstand almost anything. The only problem is 
> power dissipation - 5mA with 50 volts drop across current limiting circuit 
> is 0,25W. With such constant current design one should lower HV voltage to 
> minimum (just above striking point of all nixies), normally the 
> significantly higher voltage (200V) is used to make choosing limiting 
> resistor easier.
>
> W dniu poniedziałek, 27 marca 2017 04:17:46 UTC+2 użytkownik gregebert 
> napisał:
>>
>> I dont see anything fundamentally wrong; I just have paranoia about 
>> running devices in an environment where this is potential for overvoltage. 
>> The LM317 is rated for ~35V, and the HV supply is around 180V, so you are 
>> relying on the voltage drop across the nixie tube. There are all kinds of 
>> unexpected things that happen during power-up/down; maybe there are 
>> scenarios that could damage the LM317.
>>
>>
>>
>>
>>

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[neonixie-l] Re: Constant current source design

[ZY]

I'd like some opinions on using something like a LM317 inline on the high 
side, as in the image attached. I've tested it and it seems to work 
although maybe there is a flaw that I'm not seeing somewhere.

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Re: [neonixie-l] Some vintage LED displays

[ZY]

I haven't heard of these before. I know OSRAM uses a DLO code for their 
"high effiency red" color. Are they similar to the OSRAM DLO3416 or DLO2416?

On Sunday, 19 March 2017 12:00:41 UTC-4, Jonathan wrote:
>
> I just ran across some DLO-3130 displays. Do you have any information on 
> them?
>
> Thanks!
>
> Jonathan
>
> On 3/11/2017 8:45 PM, ZY wrote:
>
> Not sure if anyone would be interested as they're not neon, but here's a 
> portion of my LED display collection if anyone is into that too: 
>
> https://imgur.com/a/AVp0y
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>
>

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[neonixie-l] Some vintage LED displays

[ZY]

Not sure if anyone would be interested as they're not neon, but here's a 
portion of my LED display collection if anyone is into that too:

https://imgur.com/a/AVp0y

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[neonixie-l] CD12 on eBay

[ZY]

Not my lot (I wish!) but some of you might be interested:

http://www.ebay.com/itm/1x-NIXIE-TUBE-CD12-RODAN-OKAYA-Socket-NOS-ultre-rare-very-large-Nixie-tube/112292764752

Seems very expensive though.

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Re: [neonixie-l] I agree with the Rant - eBay Sucks ! Shipping Calculator

[ZY]

The GSP really sucks. I also ordered from Canada while living there for a 
short while and something for ~$5 came with $20 shipping and other fees.

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[neonixie-l] Re: Constant current regulator for Nixies

[ZY]

What is your method of current regulation? For example, do you use a PnP 
transistor or the lm317 method, or something else? I have room to add 
something for my anodes, but I'm unsure if using a transistor would be 
accurate.

On Sunday, 14 August 2016 03:02:17 UTC-4, gregebert wrote:
>
> I use current-regulation on my nixie designs, and I've done cathode-side 
> as well as anode-side regulation.  Where you decide to regulate the current 
> depends upon the driver you select. So far, all of my designs use 
> direct-drive (non-multiplexed).
>
> My 'Tomorrowland' clock uses HV5532 drivers (it has fourteen IN-18 tubes), 
> so I regulate current on each anode. Yes, there are 14 current 
> regulators My wristwatch uses NPN transistors to drive the cathodes, so 
> I regulate the current on each segment.
>
> Since 10mA fuses really aren't available, I size the resistor in the 
> current-regulator so that it will operate at about 1/2 it's rated power 
> during normal operation. For example, an 0805 SMT resistor is rated for 1/8 
> Watt, so I try to design for around 50-60mW. If a gross failure in the 
> regulator occurs, the resistor should overheat and open. I have not tested 
> it, though. I have a fuse on the power supply, and use the smallest value 
> that will handle max operating current.
>
> If you really want to be paranoid, monitor all of your anode currents with 
> a multi-channel ADC. I've never done that, but it sounds like a fun project.
>
> For cathode current-regulation, you would use an NPN or NMOS transistor; 
> anode-side would use a PNP or PMOS. I found that high-voltage PMOS devices 
> aren't nearly as common as NMOS.
>
> If you use MOS devices, I'd recommend a zener-diode across gate-source and 
> also very-high resistors (10Meg +) across drain-source to protect from ESD 
> or unanticipated voltage spikes. It's probably overkill but SMT devices are 
> so cheap and small it's worth the cost to me.
>

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[neonixie-l] Constant current regulator for Nixies

[ZY]

Hello. I'm wondering if people typically use some sort of constant current 
regulator for their nixie clocks? Such as a simple LM317 current regulator 
at the anode instead of a current limiting resistor? I just started 
designing a circuit for some IN-18 tubes and since they were so expensive 
maybe some regulation circuitry would be worth it in the long run?

Do you guys also typically fuse each anode?

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Re: [neonixie-l] Re: Burroughs Panaplex II clock display...

[ZY]

Ah I see. That has me wondering what a nixie tube made completely out of 
uranium glass would look like.

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[neonixie-l] Re: Burroughs Panaplex II clock display...

[ZY]

What does the Kr85 stand for? I see it on one of my displays too.

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Re: [neonixie-l] Re: Help required on nixie power supply

[ZY]

Just an update. A 100pF cap over the resistor has indeed fixed the issue.
 

> Noise on the FB pin is a common problem with poor layout, hence asking for 
> a look at it.
>

I thought my layout would be ok. Maybe I'll remove the ground-plane keepout 
under the inductor next time as I'm using a shielded one to have less 
interruptions on the ground plane, and maybe I have to have a better 12V 
input to the IC. I thought my spacing and routing would be fine though, so 
I'm not sure.

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[neonixie-l] Re: Take a look at this....

[ZY]

Earnshaw's theorem actually states that it's impossible to use static 
magnets to levitate no matter how you create the field without some 
supporting surface touching the levitating surface at some position (like a 
pole) which of course doesn't count as levitation. You have to use 
active stabilisation with electromagnets.

On Thursday, 21 July 2016 15:02:34 UTC-4, threeneurons wrote:
>
>
> Just as a clarification:
>
> 1) No power required for levitation
>

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[neonixie-l] Re: Help required on nixie power supply

[ZY]

Also here is an attachment showing what the entire assembly looks like at 
the moment. The two boards on the back are for power and control, and are 
not finished yet as I'm still testing/assembling.

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[neonixie-l] Re: Help required on nixie power supply

[ZY]

Oops I meant 0.1nF for the capacitor across the 1.5M resistor, although I'm 
assuming 0.1uF would still be ok?

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[neonixie-l] Re: Help required on nixie power supply

[ZY]

It seems like that is the issue. I can't find a suitable capacitor at the 
moment as the 0.1uF ones I have extra right now are rated at 50V, but using 
my multimeter to probe across the 1.5M cap causes enough parasitic 
capacitance to allow for a stable voltage output. I will order a similarly 
sized one as the resistor and solder it on top.

Also my output capacitors are a 10uF electrolytic capacitor, and a 2.2uF 
and 0.1uF ceramic capacitor, all three rated at 250V. 

On Thursday, 14 July 2016 01:38:57 UTC-4, SWISSNIXIE - Jonathan F. wrote:
>
> Have you tried to use a small capacitor 10-100pf on top of the resistor 
> (the high value one, 1.5Meg or so) thats forming a voltage divider for the 
> feedback? 
> This can really help. 
>
> What kind of output cap have you used?
>
>

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[neonixie-l] Help required on nixie power supply

[ZY]

Hello. I'm following desmith's guide to building a power supply, and I'm 
using a circuit somewhat similar to his except I've selected some different 
components due to some size constraints. The main difference is my mosfet 
is this guy: 
https://www.digikey.com/product-detail/en/toshiba-semiconductor-and-storage/TPH5200FNH,L1Q/TPH5200FNHL1QCT-ND/5456292

Anyway, my no-load output swings from 250V to 150V over the course of 
several seconds, during which there is no activity on the EXT pin. The 
output is basically just dropping due to leakage resistance. Once the 
output reaches 150V, I see switching activity on the EXT pin and the output 
quickly shoots up to 250V, and then switching activity stops again. This 
cycle just repeats. Putting a load of a single nixie on the output does not 
change the behaviour.

If I ground the FB pin, instead of seeing 12V at the output as expected I 
see something like 300-310V.

My FB pin usually sits around 1.7-1.8V as the voltage swings up and down. 
My Ref pin is at 1.5V as expected. My input voltage is 12V.

Can anyone give me some insight as to what is happening? I have attached a 
snippet of the circuit showing the HV supply portion.

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Re: [neonixie-l] Anyone selling IEL-0-IV or the more rare IEL-0-VI?

[ZY]

You should also try looking at I-209 and I-195 displays. They look to be 
much larger than the IEL ones. You can see a few as the first few images of 
this google search:
https://www.google.com/search?q=I-209+electroluminescent+display=lnms=isch=X=0ahUKEwj30a7-3rrNAhVJ1h4KHfxXBRUQ_AUICSgC=919=635#imgrc=_

They seem to pop up quite often on Ebay.

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[neonixie-l] Re: Boost converter inductor sizing question

[ZY]

Oh nono, I haven't built it yet. I was just wondering why the equation from 
wikipedia doesn't work. More of a theory based question than a practical 
one.

I was going to go with this coil 
though: 
https://www.digikey.com/product-detail/en/wurth-electronics-inc/7447709101/732-1248-1-ND/1639309
since I already had the footprint for it in my Eagle library.

On Wednesday, 18 May 2016 15:49:36 UTC-4, threeneurons wrote:
>
> Is it regulating ? If overloaded, it can never get to that voltage.
>
> As Nick stated, if you followed guidelines faithfully, there should be no 
> issues. That's a pretty finicky chip, if misused. 
>
> What's the rating on the coil ? Can you give us its part number. I did not 
> see a current rating. The coil, is the most important part, of a boost 
> supply.
>
> On Wednesday, May 18, 2016 at 12:35:20 PM UTC-7, ZY wrote:
>>
>> Thanks for the replies. I'm currently building one using the guidelines 
>> from the website, but I'm still curious why the Vo equation in theory is 
>> way off compared to the real life version?
>>
>

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[neonixie-l] Re: Boost converter inductor sizing question

[ZY]

Thanks for the replies. I'm currently building one using the guidelines 
from the website, but I'm still curious why the Vo equation in theory is 
way off compared to the real life version?

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[neonixie-l] Boost converter inductor sizing question

[ZY]

Hello. I'm trying to build a boost converter for my project to boost 12V to 
150-220V. I'm looking at various converter circuits online, like this one: 
http://desmith.net/NMdS/Electronics/NixiePSU.html, and they use inductors 
on the order of 100uH to 150uH, and use drivers that switch at something 
like 300KHz. But when I look at the wikipedia equation for discontinuous 
mode output voltage, it's this: 

Vo = Vi * (1+Vi * D^2 * T)/(2*L*Io)

If I plug in Vi = 12V, D = 0.92, T = 1/30, L = 0.0001, and Io = 0.025, 
I get something like 93V, which is far from what I want to be at. So I'm 
curious about what I'm doing wrong here.

Also, from what I've read so far, it seems like it's bad to switch between 
continuous and discontinuous modes due to stability? Since my digits would 
turn on and off, my current draw can swing wildly, so I can't really 
guarantee that I would stay in one mode right? Do modern controller ICs 
just handle this without us having to worry about it?


Also just an extra tag along question. I see some nixies use anode 
resistors when they already have cathode resistors. What is the point of 
the anode resistor? Wouldn't the cathode resistor already limit the 
current? I'm looking at the SP-101 Panaplex datasheet and they have a 2.2k 
anode resistor. Wouldn't this affect the brightness depending on how many 
segments are turned on?

Thanks in advance.

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