Re: [neonixie-l] Re: Stuck with a stuck dekatron

[Tidak Ada]

Thanks John, that is useful information!
Yes, you confirm my fear. Fortunately I bought the tube as am collecting item,
 Eric

Verstuurd vanaf mijn iPhone

> Op 23 feb. 2022 om 23:21 heeft Jon  het volgende 
> geschreven:
> 
> To Eric's question on the N3...
> 
> These are also rather tricky tubes. My experience is similar to Martin's - 
> unfortunately many examples of N3 are non-functional in that they won't even 
> strike a glow - outgassed or similar. I fear that if you can't raise a glow 
> with a violet ray unit or plasma globe then yours may be dead :(
> 
> But if you do find a working N3 or N4, then the conditions below work for me:
> Va = +350V with respect to main cathodes
> Transfer pulses 30V amplitude from a resting bias +15V with respect to main 
> cathodes
> Anode current 1.6mA (82K anode resistor, 8K2 cathode resistors)
> It's quite an unusual design with relatively low anode and transfer electrode 
> voltages. If the anode voltage or current is too high, it's easy to get 
> multiple cathodes glowing instead of just one which can mess up the stepping.
> 
> Jon.
> 
> 
>> On Wednesday, February 23, 2022 at 10:04:53 PM UTC Jon wrote:
>> The sticking on K10 specifically is a peculiarity of the 6167 in my 
>> experience. I believe it's distinct from the sleeping sickness effect that 
>> Martin describes as that is essentially random in which cathodes are 
>> affected (and as he says, working the tube, possibly at elevated current, in 
>> both directions where possible, is usually an effective cure).
>> 
>> I mostly saw K10 sticking when I was exploring a circuit that makes use of 
>> the unique auxiliary anode connection (pin 5) which of course lies adjacent 
>> to K10. What seems to be happening was that when the glow gets to K10 there 
>> is current flow from both the main anode and auxiliary anode. The next 
>> transfer pulse moves the glow onto the transfer electrode, but when it 
>> terminates the auxiliary anode-K10 gap is still sufficiently primed so that 
>> the glow mostly steps back to K10 rather than forward to K1. I was able to 
>> mitigate this by reducing the auxiliary anode potential below what I'd 
>> originally understood it needed to be from the datasheet (the datasheet is 
>> really opaque on this point), and also by lengthening the transfer pulse to 
>> allow more deionisation time.
>> 
>> However, if I understand Paolo's post, he's using Mike Moorrees's circuit 
>> (https://threeneurons.files.wordpress.com/2011/09/we6167ckt.gif) which 
>> leaves the auxiliary anode disconnected. When I ran 6167s in this 
>> configuration they were generally much more reliable in not sticking on K10, 
>> though I was using rather different circuit conditions:
>> Va = +400V with respect to main cathodes
>> Transfer pulses 60V amplitude from a resting bias +30V with respect to main 
>> cathodes
>> Anode current 1.3mA
>> 
>> Paolo, can you confirm you have indeed left pin 5 unconnected? If so, given 
>> that the sticking effect seems to be increasing with tube use, I wonder if 
>> we're seeing the floating auxiliary anode gradually charging up and 
>> eventually reaching a potential which is disrupting the stepping operation. 
>> Maybe use a potentiometer or potential divider to pin the auxiliary anode at 
>> some moderate voltage positive to the main cathodes (say +100V as a starting 
>> point) and see if that helps?
>> 
>> They're funky tubes...
>> 
>> Jon.
>> 
>> 
>>> On Wednesday, February 23, 2022 at 8:37:58 AM UTC Paolo Cravero wrote:
>>> Hello.
>>> I am stuck with a stubborn WE-6167 dekatron 
>>> (http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf seems to be the 
>>> only document available).
>>> 
>>> The tube is NIB made in 1958. I understand it is a single guide dekatron, 
>>> and the stepping cathodes are split in two groups 1-5 and 6-10.
>>> 
>>> I built the circuit as per Mike's diagram 
>>> (http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf) and it span 
>>> correctly. I let it run for few minutes and then it got stuck at K10. 
>>> Through the glass I can see that it attempts to jump ahead, but the main 
>>> glow stays on K10. Fiddling with wires I could get it have one round up to 
>>> K10. The more it runs the more it gets stickier. The relaxation oscillator 
>>> never stops.
>>> 
>>> I suspected some resistor overheating or changing value, but even after 
>>> hours of power-off, it doesn't go beyond K10. Or it simply powers up at K10 
>>> and doesn't step over, while it does visually try to jump.
>>> 
>>> Voltages are 450V/225V (input at 12V is 220 mA). Anode current is 1 mA (I 
>>> increased the anode resistor to 250k) while the current coming out of the 
>>> active cathode(s) is 1.5 mA. Stepping goes from 200V down to 2V (green 
>>> trace). Anode voltage (450 V) doesn't sag noticeably and inductor+IRF get 
>>> barely warm. The yellow trace in the oscilloscope shot is  measured at the 
>>> "+58V" point (yes, I did try to move that voltage up and down with 

[neonixie-l] Re: Stuck with a stuck dekatron

[Jon]

To Eric's question on the N3...

These are also rather tricky tubes. My experience is similar to Martin's - 
unfortunately many examples of N3 are non-functional in that they won't 
even strike a glow - outgassed or similar. I fear that if you can't raise a 
glow with a violet ray unit or plasma globe then yours may be dead :(

But if you do find a working N3 or N4, then the conditions below work for 
me:

   - Va = +350V with respect to main cathodes
   - Transfer pulses 30V amplitude from a resting bias +15V with respect to 
   main cathodes
   - Anode current 1.6mA (82K anode resistor, 8K2 cathode resistors)

It's quite an unusual design with relatively low anode and transfer 
electrode voltages. If the anode voltage or current is too high, it's easy 
to get multiple cathodes glowing instead of just one which can mess up the 
stepping.

Jon.


On Wednesday, February 23, 2022 at 10:04:53 PM UTC Jon wrote:

> The sticking on K10 specifically is a peculiarity of the 6167 in my 
> experience. I believe it's distinct from the sleeping sickness effect that 
> Martin describes as that is essentially random in which cathodes are 
> affected (and as he says, working the tube, possibly at elevated current, 
> in both directions where possible, is usually an effective cure).
>
> I mostly saw K10 sticking when I was exploring a circuit that makes use of 
> the unique auxiliary anode connection (pin 5) which of course lies adjacent 
> to K10. What seems to be happening was that when the glow gets to K10 there 
> is current flow from both the main anode and auxiliary anode. The next 
> transfer pulse moves the glow onto the transfer electrode, but when it 
> terminates the auxiliary anode-K10 gap is still sufficiently primed so that 
> the glow mostly steps back to K10 rather than forward to K1. I was able to 
> mitigate this by reducing the auxiliary anode potential below what I'd 
> originally understood it needed to be from the datasheet (the datasheet is 
> really opaque on this point), and also by lengthening the transfer pulse to 
> allow more deionisation time.
>
> However, if I understand Paolo's post, he's using Mike Moorrees's circuit (
> https://threeneurons.files.wordpress.com/2011/09/we6167ckt.gif) which 
> leaves the auxiliary anode disconnected. When I ran 6167s in this 
> configuration they were generally much more reliable in not sticking on 
> K10, though I was using rather different circuit conditions:
>
>- Va = +400V with respect to main cathodes
>- Transfer pulses 60V amplitude from a resting bias +30V with respect 
>to main cathodes
>- Anode current 1.3mA
>
>
> Paolo, can you confirm you have indeed left pin 5 unconnected? If so, 
> given that the sticking effect seems to be increasing with tube use, I 
> wonder if we're seeing the floating auxiliary anode gradually charging up 
> and eventually reaching a potential which is disrupting the stepping 
> operation. Maybe use a potentiometer or potential divider to pin the 
> auxiliary anode at some moderate voltage positive to the main cathodes (say 
> +100V as a starting point) and see if that helps?
>
> They're funky tubes...
>
> Jon.
>
>
> On Wednesday, February 23, 2022 at 8:37:58 AM UTC Paolo Cravero wrote:
>
>> Hello.
>> I am stuck with a stubborn WE-6167 dekatron (
>> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf seems to be the 
>> only document available).
>>
>> The tube is NIB made in 1958. I understand it is a single guide dekatron, 
>> and the stepping cathodes are split in two groups 1-5 and 6-10.
>>
>> I built the circuit as per Mike's diagram (
>> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf) and it span 
>> correctly. I let it run for few minutes and then it got stuck at K10. 
>> Through the glass I can see that it attempts to jump ahead, but the main 
>> glow stays on K10. Fiddling with wires I could get it have one round up to 
>> K10. The more it runs the more it gets stickier. The relaxation oscillator 
>> never stops.
>>
>> I suspected some resistor overheating or changing value, but even after 
>> hours of power-off, it doesn't go beyond K10. Or it simply powers up at K10 
>> and doesn't step over, while it does visually try to jump.
>>
>> Voltages are 450V/225V (input at 12V is 220 mA). Anode current is 1 mA (I 
>> increased the anode resistor to 250k) while the current coming out of the 
>> active cathode(s) is 1.5 mA. Stepping goes from 200V down to 2V (green 
>> trace). Anode voltage (450 V) doesn't sag noticeably and inductor+IRF get 
>> barely warm. The yellow trace in the oscilloscope shot is  measured at the 
>> "+58V" point (yes, I did try to move that voltage up and down with no 
>> difference).
>>
>>
>> Then I opened a second new in box WE-6167. It ran correctly for a minute, 
>> perhaps 100 rounds, then it started hiccupping (I think between K5 and K6) 
>> and finally got stuck on K10 with the flicker towards the stepping cathode.
>>
>> It must be something with these tubes. 

[neonixie-l] Re: Stuck with a stuck dekatron

[Jon]

The sticking on K10 specifically is a peculiarity of the 6167 in my 
experience. I believe it's distinct from the sleeping sickness effect that 
Martin describes as that is essentially random in which cathodes are 
affected (and as he says, working the tube, possibly at elevated current, 
in both directions where possible, is usually an effective cure).

I mostly saw K10 sticking when I was exploring a circuit that makes use of 
the unique auxiliary anode connection (pin 5) which of course lies adjacent 
to K10. What seems to be happening was that when the glow gets to K10 there 
is current flow from both the main anode and auxiliary anode. The next 
transfer pulse moves the glow onto the transfer electrode, but when it 
terminates the auxiliary anode-K10 gap is still sufficiently primed so that 
the glow mostly steps back to K10 rather than forward to K1. I was able to 
mitigate this by reducing the auxiliary anode potential below what I'd 
originally understood it needed to be from the datasheet (the datasheet is 
really opaque on this point), and also by lengthening the transfer pulse to 
allow more deionisation time.

However, if I understand Paolo's post, he's using Mike Moorrees's circuit (
https://threeneurons.files.wordpress.com/2011/09/we6167ckt.gif) which 
leaves the auxiliary anode disconnected. When I ran 6167s in this 
configuration they were generally much more reliable in not sticking on 
K10, though I was using rather different circuit conditions:

   - Va = +400V with respect to main cathodes
   - Transfer pulses 60V amplitude from a resting bias +30V with respect to 
   main cathodes
   - Anode current 1.3mA


Paolo, can you confirm you have indeed left pin 5 unconnected? If so, given 
that the sticking effect seems to be increasing with tube use, I wonder if 
we're seeing the floating auxiliary anode gradually charging up and 
eventually reaching a potential which is disrupting the stepping operation. 
Maybe use a potentiometer or potential divider to pin the auxiliary anode 
at some moderate voltage positive to the main cathodes (say +100V as a 
starting point) and see if that helps?

They're funky tubes...

Jon.


On Wednesday, February 23, 2022 at 8:37:58 AM UTC Paolo Cravero wrote:

> Hello.
> I am stuck with a stubborn WE-6167 dekatron (
> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf seems to be the 
> only document available).
>
> The tube is NIB made in 1958. I understand it is a single guide dekatron, 
> and the stepping cathodes are split in two groups 1-5 and 6-10.
>
> I built the circuit as per Mike's diagram (
> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf) and it span 
> correctly. I let it run for few minutes and then it got stuck at K10. 
> Through the glass I can see that it attempts to jump ahead, but the main 
> glow stays on K10. Fiddling with wires I could get it have one round up to 
> K10. The more it runs the more it gets stickier. The relaxation oscillator 
> never stops.
>
> I suspected some resistor overheating or changing value, but even after 
> hours of power-off, it doesn't go beyond K10. Or it simply powers up at K10 
> and doesn't step over, while it does visually try to jump.
>
> Voltages are 450V/225V (input at 12V is 220 mA). Anode current is 1 mA (I 
> increased the anode resistor to 250k) while the current coming out of the 
> active cathode(s) is 1.5 mA. Stepping goes from 200V down to 2V (green 
> trace). Anode voltage (450 V) doesn't sag noticeably and inductor+IRF get 
> barely warm. The yellow trace in the oscilloscope shot is  measured at the 
> "+58V" point (yes, I did try to move that voltage up and down with no 
> difference).
>
>
> Then I opened a second new in box WE-6167. It ran correctly for a minute, 
> perhaps 100 rounds, then it started hiccupping (I think between K5 and K6) 
> and finally got stuck on K10 with the flicker towards the stepping cathode.
>
> It must be something with these tubes. Does anyone remember a similar 
> behaviour in never used dekatrons? I've read of deks needing a high current 
> "preparation", but not of them failing after a good start. I would like to 
> get out of the K10 position!
>
> Thanks,
> Paolo
>
>

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Re: [neonixie-l] Re: Stuck with a stuck dekatron

[gregebert]

When I had initial problems with my A101, I increased the steering voltage 
by using a larger cathode resistor and it's worked flawlessly ever since. I 
couldn't tell from posted scope trace what the measurement was. Also, you 
want to have overlapping waveforms, with no dead-time, to ensure the gas is 
always ionized. Again, with my A101 as an example, I have 3 driver 
transistors, A, B, and C where "A" is all 10 cathodes tied together, and B 
& C are the steering cathodes. The 6-stage sequence is A-> AB ->B ->BC -> C 
-> CA -> A (repeat). To reverse the direction, swap the sequencing of B 



On Wednesday, February 23, 2022 at 1:33:00 PM UTC-8 Tidak Ada wrote:

> Hi Martin,
>
>  
>
> No, I was not aware, despite Giorgio is a friend of me….
>
>  
>
> Thanks for your tip and  experience
>
>  
>
> Eric
>
>  
>
>  
>
> *Van:* neoni...@googlegroups.com [mailto:neoni...@googlegroups.com] *Namens 
> *Dekatron42
> *Verzonden:* woensdag 23 februari 2022 13:06
> *Aan:* neonixie-l
> *Onderwerp:* Re: [neonixie-l] Re: Stuck with a stuck dekatron
>
>  
>
> Regarding the Pressler N3, I hope you have seen the datasheet here: 
> http://lampes-et-tubes.info/cd/N3.pdf
>
>  
>
> Out of the bunch that I own of these only a few are running (and maybe 
> half are out-gassed and some have mechanical faults like loose welds and 
> pins rumbling around inside the envelope) with the original circuit.
>
>  
>
> /Martin
>
>  
>
>  
>
>  
>
> On Wednesday, 23 February 2022 at 12:04:19 UTC+1 Tidak Ada wrote:
>
> Hi all,
>
>  
>
>  
>
> Unfortunately no further info here.
>
> A guess is it a kind of cathode poisoning??
>
>  
>
> Did you already contact the *TCA* [ tubecollecto...@groups.io ]. They are 
> based in the USA, so the chance is greater there is info to find.
>
>  
>
> I have the same problem with a rare Pressler N3 dekatron. Anybody her who 
> can help me on data and applications?
>
> The Pressler N3 is a WW-II tube with a 8 pin ‘German Stahlrohren’ base.
>
> I have no data and therefore no clue how to drive the tube.
>
> Trying to light up the tube with a blue-ray machine did not work
>
>  
>
> Cheers,
>
> Eric
>
>  
>
> *Van:* neoni...@googlegroups.com [mailto:neoni...@googlegroups.com] *Namens 
> *Dekatron42
> *Verzonden:* woensdag 23 februari 2022 10:09
> *Aan:* neonixie-l
> *Onderwerp:* [neonixie-l] Re: Stuck with a stuck dekatron
>
>  
>
> -- 
> 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.
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> https://groups.google.com/d/msgid/neonixie-l/ec4d3629-f38a-4fcc-9ffd-3044de6fa6a3n%40googlegroups.com
>  
> 
> .
>

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RE: [neonixie-l] Re: Stuck with a stuck dekatron

[Tidak Ada]

Hi Martin,

 

No, I was not aware, despite Giorgio is a friend of me….

 

Thanks for your tip and  experience

 

Eric

 

 

Van: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] Namens 
Dekatron42
Verzonden: woensdag 23 februari 2022 13:06
Aan: neonixie-l
Onderwerp: Re: [neonixie-l] Re: Stuck with a stuck dekatron

 

Regarding the Pressler N3, I hope you have seen the datasheet here:  
 http://lampes-et-tubes.info/cd/N3.pdf

 

Out of the bunch that I own of these only a few are running (and maybe half are 
out-gassed and some have mechanical faults like loose welds and pins rumbling 
around inside the envelope) with the original circuit.

 

/Martin

 

 

 

On Wednesday, 23 February 2022 at 12:04:19 UTC+1 Tidak Ada wrote:

Hi all,

 

 

Unfortunately no further info here.

A guess is it a kind of cathode poisoning??

 

Did you already contact the TCA [ tubecollecto...@groups.io ]. They are based 
in the USA, so the chance is greater there is info to find.

 

I have the same problem with a rare Pressler N3 dekatron. Anybody her who can 
help me on data and applications?

The Pressler N3 is a WW-II tube with a 8 pin ‘German Stahlrohren’ base.

I have no data and therefore no clue how to drive the tube.

Trying to light up the tube with a blue-ray machine did not work

 

Cheers,

Eric

 

Van: neoni...@googlegroups.com [mailto:neoni...@googlegroups.com] Namens 
Dekatron42
Verzonden: woensdag 23 februari 2022 10:09
Aan: neonixie-l
Onderwerp: [neonixie-l] Re: Stuck with a stuck dekatron

 

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 .

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Re: [neonixie-l] Re: Stuck with a stuck dekatron

[Dekatron42]

Regarding the Pressler N3, I hope you have seen the datasheet here: 
http://lampes-et-tubes.info/cd/N3.pdf

Out of the bunch that I own of these only a few are running (and maybe half 
are out-gassed and some have mechanical faults like loose welds and pins 
rumbling around inside the envelope) with the original circuit.

/Martin



On Wednesday, 23 February 2022 at 12:04:19 UTC+1 Tidak Ada wrote:

> Hi all,
>
>  
>
>  
>
> Unfortunately no further info here.
>
> A guess is it a kind of cathode poisoning??
>
>  
>
> Did you already contact the *TCA* [ tubecollecto...@groups.io ]. They are 
> based in the USA, so the chance is greater there is info to find.
>
>  
>
> I have the same problem with a rare Pressler N3 dekatron. Anybody her who 
> can help me on data and applications?
>
> The Pressler N3 is a WW-II tube with a 8 pin ‘German Stahlrohren’ base.
>
> I have no data and therefore no clue how to drive the tube.
>
> Trying to light up the tube with a blue-ray machine did not work
>
>  
>
> Cheers,
>
> Eric
>
>  
>
> *Van:* neoni...@googlegroups.com [mailto:neoni...@googlegroups.com] *Namens 
> *Dekatron42
> *Verzonden:* woensdag 23 februari 2022 10:09
> *Aan:* neonixie-l
> *Onderwerp:* [neonixie-l] Re: Stuck with a stuck dekatron
>
>  
>

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RE: [neonixie-l] Re: Stuck with a stuck dekatron

[Tidak Ada]

Hi all,

 

 

Unfortunately no further info here.

A guess is it a kind of cathode poisoning??

 

Did you already contact the TCA [ tubecollectorsassociat...@groups.io ]. They 
are based in the USA, so the chance is greater there is info to find.

 

I have the same problem with a rare Pressler N3 dekatron. Anybody her who can 
help me on data and applications?

The Pressler N3 is a WW-II tube with a 8 pin ‘German Stahlrohren’ base.

I have no data and therefore no clue how to drive the tube.

Trying to light up the tube with a blue-ray machine did not work

 

Cheers,

Eric

 

Van: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] Namens 
Dekatron42
Verzonden: woensdag 23 februari 2022 10:09
Aan: neonixie-l
Onderwerp: [neonixie-l] Re: Stuck with a stuck dekatron

 

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[neonixie-l] Re: Stuck with a stuck dekatron

[Dekatron42]

I see this a lot in some Dekatron types/brands that have been stored for a 
long time, some brands have fared better while being stored compared to 
others and some very´seldom experience this problem. I usually just 
increase the current either by raising the Anode voltage or decreasing the 
Anode resistor and then let them sit for a few hours up to a day or so and 
they usually start to run again past the sticky point. In those that you 
can reverse the rotation I sometimes switch the direction back and forth so 
I know that they run well in both directions.

/Martin

On Wednesday, 23 February 2022 at 09:37:58 UTC+1 Paolo Cravero wrote:

> Hello.
> I am stuck with a stubborn WE-6167 dekatron (
> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf seems to be the 
> only document available).
>
> The tube is NIB made in 1958. I understand it is a single guide dekatron, 
> and the stepping cathodes are split in two groups 1-5 and 6-10.
>
> I built the circuit as per Mike's diagram (
> http://www.tube-tester.com/sites/nixie/dat_arch/6167.pdf) and it span 
> correctly. I let it run for few minutes and then it got stuck at K10. 
> Through the glass I can see that it attempts to jump ahead, but the main 
> glow stays on K10. Fiddling with wires I could get it have one round up to 
> K10. The more it runs the more it gets stickier. The relaxation oscillator 
> never stops.
>
> I suspected some resistor overheating or changing value, but even after 
> hours of power-off, it doesn't go beyond K10. Or it simply powers up at K10 
> and doesn't step over, while it does visually try to jump.
>
> Voltages are 450V/225V (input at 12V is 220 mA). Anode current is 1 mA (I 
> increased the anode resistor to 250k) while the current coming out of the 
> active cathode(s) is 1.5 mA. Stepping goes from 200V down to 2V (green 
> trace). Anode voltage (450 V) doesn't sag noticeably and inductor+IRF get 
> barely warm. The yellow trace in the oscilloscope shot is  measured at the 
> "+58V" point (yes, I did try to move that voltage up and down with no 
> difference).
>
>
> Then I opened a second new in box WE-6167. It ran correctly for a minute, 
> perhaps 100 rounds, then it started hiccupping (I think between K5 and K6) 
> and finally got stuck on K10 with the flicker towards the stepping cathode.
>
> It must be something with these tubes. Does anyone remember a similar 
> behaviour in never used dekatrons? I've read of deks needing a high current 
> "preparation", but not of them failing after a good start. I would like to 
> get out of the K10 position!
>
> Thanks,
> Paolo
>
>

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