Re: [neonixie-l] Another Tube Hobby Failure

[Bill Notfaded]

You mean the smaller Taylor supply won't fit??? I'd find a way to squeezed 
John's in there.  ;^}

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Re: [neonixie-l] Another Tube Hobby Failure

[gregebert]

#1 Make sure you are purchasing new units from a reputable supplier; there 
are fake parts out there that are poor quality. Never re-use salvaged 
electrolytics.
#2 Heat will shorten the life of any electrolytic; it only takes a few 
well-placed vent holes to keep things cool.
#3 Not all electrolytics are created equal; ESR and lifetime specs specs 
vary by manufacturer
#4 Choose a manufacturer that provides datasheet info for extended 
operation; EPCOS has devices spec'd for 200,000 hours at 40C. Note that any 
capacitor will last longer at lower temperatures.

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Re: [neonixie-l] Another Tube Hobby Failure

[Roger Brinkman]

This is the Multilayer Ceramic Capacitor I had in mind in my suggestion earlier 
in the thread, datasheet impedance looks suitable, and I suspect its life will 
be much longer than an electrolytic. Even though it’s an SMD part, it should be 
able to easily be soldered in place of the electro. I’m going to order some and 
install, will post results.

Roger Brinkman 
Australia

https://au.element14.com/murata/grm55dr72e105kw01l/cap-1-f-250v-10-x7r-2220/dp/1828845?st=MLCC%20105%20250v


https://au.element14.com/murata/grm55dr72e105kw01l/cap-1-f-250v-10-x7r-2220/dp/1828845?st=MLCC%20105%20250v

> On 8 Apr 2019, at 12:44 am, MichaelB  wrote:
> 
> I used a Lelon (the new Xicon) 1uf 350V 85° C vs. the 1uf 250V that's 
> recommended.
> 
>> On Saturday, April 6, 2019 at 6:59:51 PM UTC-7, Terry Bowman wrote:
>> 
>>> On Apr 6, 2019, at 9:36 PM, MichaelB  wrote:
>>> 
>>> I used a higher voltage capacity electrolytic this time, maybe I’ll this'll 
>>> give me another year or so :-).
>> 
>> Are you using 85°C or 105°C?
>> 
>> 
>>> and I will try your idea of adding a heat sink to the VREG, since heat 
>>> seems to be the culprit here. Thx Nick
>> 
>> Never turn your back on a 78xx. You could try using a 317 instead (requires 
>> a resistor).
>> 
>> 
>> Terry Bowman, KA4HJH
>> "The Mac Doctor"
>> 
> 
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Re: [neonixie-l] Another Tube Hobby Failure

[MichaelB]

I used a Lelon (the new Xicon) 1uf 350V 85° C vs. the 1uf 250V that's 
recommended.

On Saturday, April 6, 2019 at 6:59:51 PM UTC-7, Terry Bowman wrote:
>
>
> On Apr 6, 2019, at 9:36 PM, MichaelB > 
> wrote:
>
> I used a higher voltage capacity electrolytic this time, maybe I’ll 
> this'll give me another year or so :-). 
>
>
> Are you using 85°C or 105°C?
>
>
> and I will try your idea of adding a heat sink to the VREG, since heat 
> seems to be the culprit here. Thx Nick
>
>
> Never turn your back on a 78xx. You could try using a 317 instead 
> (requires a resistor).
>
>
> Terry Bowman, KA4HJH
> "The Mac Doctor" 
>
>

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Re: [neonixie-l] Another Tube Hobby Failure

[MichaelB]

You guys have made me curious now about the other 'good' clock I have of 
his. I'm going to open it up and see if there are any other differences 
other than the obvious being tube board I used vs. the 'stock' one.

On Saturday, April 6, 2019 at 10:26:30 PM UTC-7, johnk wrote:
>
> Michael, I have to comment on the logic here.
>
> You say you have one that is quite OK and seem to use that fact to rule 
> out the effects mentioned by Nick. Actually, I consider that the parasitic 
> oscillations idea is reinforced by your fact, not denied by it.   When a 
> circuit is on the verge of misbehaving there will be some that are OK and 
> some that aren’t.
>
> Obviously I can’t tell from here what the actual fault is.
>
>  
>
> Capacitors.  I am interested in the topic. Low ESR electrolytics are a 
> curse. [Remember that fuss about the “stolen” formula not being complete 
> and all the computer manufacturers being affected?] Some do seem to last 
> better than expected. Some fail quickly. The LED lighting industry is 
> possibly going to cause improvements. Those tiny electros that they hide in 
> the base of the globe really are stressed. And some sellers still quote the 
> expected LED life as that for the power supply too ! Oops.  [And 
> Australian consumer law provides for lifetime warranty btw, regardless of 
> what the manufacturer states. And we beat up Steam to the point that they 
> allow returns!]
>
> I am very interested in hearing about how well different brands and types 
> of capacitor perform. Anyone tried non-electros? 
>
> I have noticed that some switching supplies driving discharge tubes for TV 
> and laptop backlighting [yeah, old ones, not LED ones] use monolithic solid 
> caps. One I fixed had only 2uF though iirc.  A pity that opamp capacitor 
> multipliers don’t store energy J .
>
>  
>
> John K
>
> Australia 
>
> *From:* neoni...@googlegroups.com  [mailto:
> neoni...@googlegroups.com ] *On Behalf Of *MichaelB
> *Sent:* Sunday, 7 April 2019 11:06
> *To:* neonixie-l
> *Subject:* Re: [neonixie-l] Another Tube Hobby Failure
>
>  
>
> HI Nick, 
>
>  
>
> I know you have mentioned that before, but I really don’t think anything 
> else is wrong. As I said I have another one of these with 566M tubes and it 
> has worked flawlessly for 8+ years. Those electronics are in a similar 
> enclosure with less ventilation. And this is the second set of electronics 
> i have tried in this enclosure thinking there might be something internally 
> wrong with the PCB. (I had that problem with one of my Thomas clocks way 
> back when) But, I believe others have had issues with these electronics. 
> Another variable vs. your clocks might be that I have wired in a pair of 
> NE-2 Colons in parallel vs. the stock config that uses just one per each 
> side. I doubt that would be an issue, but it may account for a slightly 
> greater current demand.  I don't think these clocks like anything, but an 
> open air set up. Also, the close proximity of the 5V VREG and the IRF640 is 
> somewhat suspect from a heat dissipation perspective. Anyway…I used a 
> higher voltage capacity electrolytic this time, maybe I’ll this'll give me 
> another year or so :-). and I will try your idea of adding a heat sink to 
> the VREG, since heat seems to be the culprit here. Thx Nick
>
>  
>
>  
>
> On Saturday, April 6, 2019 at 6:06:36 PM UTC-7, Pramanicin wrote:
>
> Something else is awry there Michael. I have a friend with a TubeHobby 
> IN18 that i built for him that’s been running for well over 6 years now 
> with no issues. The only modification i ever made was putting an extra 
> heatsink on the regulator as what was there (board plane) didn’t seem 
> sufficient to me (just a hunch, I’m sure Jonas knew what he was doing..)
>
>  
>
> Hope you get it sorted!
>
> Sent from my iPhone
>
>
> On Apr 6, 2019, at 17:15, MichaelB  wrote:
>
> This makes 4 times now this clock has failed over the past 10 years or so. 
> This is a stock clock with IN-18's. I have another set of these electronics 
> that has never failed, but then again, I had changed the tube board to 
> accommodate the Z566M tube. Different current demands? It has worked like a 
> charm for years now. The failure with the IN-8 clock this time was a leaky 
> C6. In the past the inductor has failed, but usually its one of the 
> electrolytics in the Pwr supply stage. It's become kind of a ritual where 
> every 2-3 years I have to pull the clock apart and play detective and 
> figure out what's wrong after its starts blowing fuses. Kind of fun now, 
> actually! 
>
> -- 
> You received this message because you are subscribed to the Google Groups 
> "neon

Re: [neonixie-l] Another Tube Hobby Failure

[MichaelB]

I've actually thought about wiring in a Taylor supply, but space is a bit 
of an issue 

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Re: [neonixie-l] Another Tube Hobby Failure

[Paul Andrews]

The short lifetime ratings of electrolytics have always worried me. 8,000 
hours? That’s about 1 year, though that is at rated operating conditions. This 
article discusses dressing of lifespan: 
https://www.allaboutcircuits.com/news/calculating-the-lifespan-of-electrolytic-capacitors-with-de-rating/

It seems temperature is definitely your enemy here.

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Re: [neonixie-l] Another Tube Hobby Failure

[David Pye]

Couldn't you wire in a small HV PSU module instead, and bypass the
circuitry for that one?

Not sure that it would necessarily have a better lifespan (depending on who
made it...)

David

On Sun, 7 Apr 2019 at 05:31, MichaelB  wrote:

> You've described my experience with this clock to a "T". If I hadn't made
> a custom enclosure around these electronics and its 'unique' tube spacing,
> I would abandon it in a heartbeat and substitute NixiChron electronics, but
> this would basically require building a whole new enclosure. It was my 1st
> enclosure build so I'm a bit attached to it. So I'll keep my fingers
> crossed and hope I can come up with a solution to this anomaly. Suggestions
> welcome
>
> On Saturday, April 6, 2019 at 7:55:19 PM UTC-7, Roger Brinkman wrote:
>>
>> I have one of these clocks too and it fails every three years or so on
>> average. It’s all down to C6. Sometimes just F1 fails and other times the
>> inductor L1 goes short circuit as well.
>> The Equivalent Series Resistance (ESR) of C6 goes through the roof,
>> causing it to effectively be a capacitor in series with a resistance. This
>> result is ringing in L1, and instability in the output voltage which
>> increases L1’s heat dissipation and untimely failure. Ambient temperature
>> is definitely a factor in C6’s lifespan, i.e clocks running in cooler
>> climates may run longer before failing, but the real mechanism of failure
>> is C6’s ability to withstand the internal heat generated by the pulse
>> current as its ESR rises with age. The higher it’s ESR, the warmer it runs,
>> then the quicker its electrolyte dries up.
>> High quality, low ESR 105 degree electrolytic capacitors designed for
>> pulse applications like the Panasonic WL-R series will have a longer life
>> than ‘ordinary’ electros but eventually even they will fail. I have thought
>> about substituting a Multilayer Ceramic Capacitor in place of electrolytic
>> C6, but currently waiting for the next failure (which is about due!) before
>> I experiment with them. Perhaps another person can comment on their
>> suitability for such an application?
>>
>> Regards from Australia!
>>
>> On 7 Apr 2019, at 11:59 am, Mac Doktor  wrote:
>>
>>
>> On Apr 6, 2019, at 9:36 PM, MichaelB  wrote:
>>
>> I used a higher voltage capacity electrolytic this time, maybe I’ll
>> this'll give me another year or so :-).
>>
>>
>> Are you using 85°C or 105°C?
>>
>>
>> and I will try your idea of adding a heat sink to the VREG, since heat
>> seems to be the culprit here. Thx Nick
>>
>>
>> Never turn your back on a 78xx. You could try using a 317 instead
>> (requires a resistor).
>>
>>
>> Terry Bowman, KA4HJH
>> "The Mac Doctor"
>>
>> --
>> 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 neoni...@googlegroups.com.
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>> To view this discussion on the web, visit
>> https://groups.google.com/d/msgid/neonixie-l/0DFF2801-AAC9-4780-9779-E01A35F1612D%40gmail.com
>> 
>> .
>> For more options, visit https://groups.google.com/d/optout.
>>
>> --
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RE: [neonixie-l] Another Tube Hobby Failure

[johnk]

Michael, I have to comment on the logic here.

You say you have one that is quite OK and seem to use that fact to rule out the 
effects mentioned by Nick. Actually, I consider that the parasitic oscillations 
idea is reinforced by your fact, not denied by it.   When a circuit is on the 
verge of misbehaving there will be some that are OK and some that aren’t.

Obviously I can’t tell from here what the actual fault is.

 

Capacitors.  I am interested in the topic. Low ESR electrolytics are a curse. 
[Remember that fuss about the “stolen” formula not being complete and all the 
computer manufacturers being affected?] Some do seem to last better than 
expected. Some fail quickly. The LED lighting industry is possibly going to 
cause improvements. Those tiny electros that they hide in the base of the globe 
really are stressed. And some sellers still quote the expected LED life as that 
for the power supply too ! Oops.  [And Australian consumer law provides for 
lifetime warranty btw, regardless of what the manufacturer states. And we beat 
up Steam to the point that they allow returns!]

I am very interested in hearing about how well different brands and types of 
capacitor perform. Anyone tried non-electros? 

I have noticed that some switching supplies driving discharge tubes for TV and 
laptop backlighting [yeah, old ones, not LED ones] use monolithic solid caps. 
One I fixed had only 2uF though iirc.  A pity that opamp capacitor multipliers 
don’t store energy J .

 

John K

Australia 

From: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] On 
Behalf Of MichaelB
Sent: Sunday, 7 April 2019 11:06
To: neonixie-l
Subject: Re: [neonixie-l] Another Tube Hobby Failure

 

HI Nick, 

 

I know you have mentioned that before, but I really don’t think anything else 
is wrong. As I said I have another one of these with 566M tubes and it has 
worked flawlessly for 8+ years. Those electronics are in a similar enclosure 
with less ventilation. And this is the second set of electronics i have tried 
in this enclosure thinking there might be something internally wrong with the 
PCB. (I had that problem with one of my Thomas clocks way back when) But, I 
believe others have had issues with these electronics. Another variable vs. 
your clocks might be that I have wired in a pair of NE-2 Colons in parallel vs. 
the stock config that uses just one per each side. I doubt that would be an 
issue, but it may account for a slightly greater current demand.  I don't think 
these clocks like anything, but an open air set up. Also, the close proximity 
of the 5V VREG and the IRF640 is somewhat suspect from a heat dissipation 
perspective. Anyway…I used a higher voltage capacity electrolytic this time, 
maybe I’ll this'll give me another year or so :-). and I will try your idea of 
adding a heat sink to the VREG, since heat seems to be the culprit here. Thx 
Nick

 

 

On Saturday, April 6, 2019 at 6:06:36 PM UTC-7, Pramanicin wrote:

Something else is awry there Michael. I have a friend with a TubeHobby IN18 
that i built for him that’s been running for well over 6 years now with no 
issues. The only modification i ever made was putting an extra heatsink on the 
regulator as what was there (board plane) didn’t seem sufficient to me (just a 
hunch, I’m sure Jonas knew what he was doing..)

 

Hope you get it sorted!

Sent from my iPhone


On Apr 6, 2019, at 17:15, MichaelB  > wrote:

This makes 4 times now this clock has failed over the past 10 years or so. This 
is a stock clock with IN-18's. I have another set of these electronics that has 
never failed, but then again, I had changed the tube board to accommodate the 
Z566M tube. Different current demands? It has worked like a charm for years 
now. The failure with the IN-8 clock this time was a leaky C6. In the past the 
inductor has failed, but usually its one of the electrolytics in the Pwr supply 
stage. It's become kind of a ritual where every 2-3 years I have to pull the 
clock apart and play detective and figure out what's wrong after its starts 
blowing fuses. Kind of fun now, actually! 

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Re: [neonixie-l] Another Tube Hobby Failure

[MichaelB]

You've described my experience with this clock to a "T". If I hadn't made a 
custom enclosure around these electronics and its 'unique' tube spacing, I 
would abandon it in a heartbeat and substitute NixiChron electronics, but 
this would basically require building a whole new enclosure. It was my 1st 
enclosure build so I'm a bit attached to it. So I'll keep my fingers 
crossed and hope I can come up with a solution to this anomaly. Suggestions 
welcome

On Saturday, April 6, 2019 at 7:55:19 PM UTC-7, Roger Brinkman wrote:
>
> I have one of these clocks too and it fails every three years or so on 
> average. It’s all down to C6. Sometimes just F1 fails and other times the 
> inductor L1 goes short circuit as well.
> The Equivalent Series Resistance (ESR) of C6 goes through the roof, 
> causing it to effectively be a capacitor in series with a resistance. This 
> result is ringing in L1, and instability in the output voltage which 
> increases L1’s heat dissipation and untimely failure. Ambient temperature 
> is definitely a factor in C6’s lifespan, i.e clocks running in cooler 
> climates may run longer before failing, but the real mechanism of failure 
> is C6’s ability to withstand the internal heat generated by the pulse 
> current as its ESR rises with age. The higher it’s ESR, the warmer it runs, 
> then the quicker its electrolyte dries up.
> High quality, low ESR 105 degree electrolytic capacitors designed for 
> pulse applications like the Panasonic WL-R series will have a longer life 
> than ‘ordinary’ electros but eventually even they will fail. I have thought 
> about substituting a Multilayer Ceramic Capacitor in place of electrolytic 
> C6, but currently waiting for the next failure (which is about due!) before 
> I experiment with them. Perhaps another person can comment on their 
> suitability for such an application?
>
> Regards from Australia! 
>
> On 7 Apr 2019, at 11:59 am, Mac Doktor > 
> wrote:
>
>
> On Apr 6, 2019, at 9:36 PM, MichaelB > 
> wrote:
>
> I used a higher voltage capacity electrolytic this time, maybe I’ll 
> this'll give me another year or so :-). 
>
>
> Are you using 85°C or 105°C?
>
>
> and I will try your idea of adding a heat sink to the VREG, since heat 
> seems to be the culprit here. Thx Nick
>
>
> Never turn your back on a 78xx. You could try using a 317 instead 
> (requires a resistor).
>
>
> Terry Bowman, KA4HJH
> "The Mac Doctor" 
>
> -- 
> You received this message because you are subscribed to the Google Groups 
> "neonixie-l" group.
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> .
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>  
> 
> .
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>
>

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Re: [neonixie-l] Another Tube Hobby Failure

[Roger Brinkman]

I have one of these clocks too and it fails every three years or so on average. 
It’s all down to C6. Sometimes just F1 fails and other times the inductor L1 
goes short circuit as well.
The Equivalent Series Resistance (ESR) of C6 goes through the roof, causing it 
to effectively be a capacitor in series with a resistance. This result is 
ringing in L1, and instability in the output voltage which increases L1’s heat 
dissipation and untimely failure. Ambient temperature is definitely a factor in 
C6’s lifespan, i.e clocks running in cooler climates may run longer before 
failing, but the real mechanism of failure is C6’s ability to withstand the 
internal heat generated by the pulse current as its ESR rises with age. The 
higher it’s ESR, the warmer it runs, then the quicker its electrolyte dries up.
High quality, low ESR 105 degree electrolytic capacitors designed for pulse 
applications like the Panasonic WL-R series will have a longer life than 
‘ordinary’ electros but eventually even they will fail. I have thought about 
substituting a Multilayer Ceramic Capacitor in place of electrolytic C6, but 
currently waiting for the next failure (which is about due!) before I 
experiment with them. Perhaps another person can comment on their suitability 
for such an application?

Regards from Australia! 

> On 7 Apr 2019, at 11:59 am, Mac Doktor  wrote:
> 
> 
>> On Apr 6, 2019, at 9:36 PM, MichaelB  wrote:
>> 
>> I used a higher voltage capacity electrolytic this time, maybe I’ll this'll 
>> give me another year or so :-).
> 
> Are you using 85°C or 105°C?
> 
> 
>> and I will try your idea of adding a heat sink to the VREG, since heat seems 
>> to be the culprit here. Thx Nick
> 
> Never turn your back on a 78xx. You could try using a 317 instead (requires a 
> resistor).
> 
> 
> Terry Bowman, KA4HJH
> "The Mac Doctor"
> 
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Re: [neonixie-l] Another Tube Hobby Failure

[Mac Doktor]

> On Apr 6, 2019, at 9:36 PM, MichaelB  wrote:
> 
> I used a higher voltage capacity electrolytic this time, maybe I’ll this'll 
> give me another year or so :-).

Are you using 85°C or 105°C?


> and I will try your idea of adding a heat sink to the VREG, since heat seems 
> to be the culprit here. Thx Nick

Never turn your back on a 78xx. You could try using a 317 instead (requires a 
resistor).


Terry Bowman, KA4HJH
"The Mac Doctor"

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Re: [neonixie-l] Another Tube Hobby Failure

[MichaelB]

HI Nick, 

I know you have mentioned that before, but I really don’t think anything 
else is wrong. As I said I have another one of these with 566M tubes and it 
has worked flawlessly for 8+ years. Those electronics are in a similar 
enclosure with less ventilation. And this is the second set of electronics 
i have tried in this enclosure thinking there might be something internally 
wrong with the PCB. (I had that problem with one of my Thomas clocks way 
back when) But, I believe others have had issues with these electronics. 
Another variable vs. your clocks might be that I have wired in a pair of 
NE-2 Colons in parallel vs. the stock config that uses just one per each 
side. I doubt that would be an issue, but it may account for a slightly 
greater current demand.  I don't think these clocks like anything, but an 
open air set up. Also, the close proximity of the 5V VREG and the IRF640 is 
somewhat suspect from a heat dissipation perspective. Anyway…I used a 
higher voltage capacity electrolytic this time, maybe I’ll this'll give me 
another year or so :-). and I will try your idea of adding a heat sink to 
the VREG, since heat seems to be the culprit here. Thx Nick


On Saturday, April 6, 2019 at 6:06:36 PM UTC-7, Pramanicin wrote:
>
> Something else is awry there Michael. I have a friend with a TubeHobby 
> IN18 that i built for him that’s been running for well over 6 years now 
> with no issues. The only modification i ever made was putting an extra 
> heatsink on the regulator as what was there (board plane) didn’t seem 
> sufficient to me (just a hunch, I’m sure Jonas knew what he was doing..)
>
> Hope you get it sorted!
>
> Sent from my iPhone
>
> On Apr 6, 2019, at 17:15, MichaelB > 
> wrote:
>
> This makes 4 times now this clock has failed over the past 10 years or so. 
> This is a stock clock with IN-18's. I have another set of these electronics 
> that has never failed, but then again, I had changed the tube board to 
> accommodate the Z566M tube. Different current demands? It has worked like a 
> charm for years now. The failure with the IN-8 clock this time was a leaky 
> C6. In the past the inductor has failed, but usually its one of the 
> electrolytics in the Pwr supply stage. It's become kind of a ritual where 
> every 2-3 years I have to pull the clock apart and play detective and 
> figure out what's wrong after its starts blowing fuses. Kind of fun now, 
> actually! 
>
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Re: [neonixie-l] Another Tube Hobby Failure

[Nicholas Stock]

Something else is awry there Michael. I have a friend with a TubeHobby IN18 
that i built for him that’s been running for well over 6 years now with no 
issues. The only modification i ever made was putting an extra heatsink on the 
regulator as what was there (board plane) didn’t seem sufficient to me (just a 
hunch, I’m sure Jonas knew what he was doing..)

Hope you get it sorted!

Sent from my iPhone

> On Apr 6, 2019, at 17:15, MichaelB  wrote:
> 
> This makes 4 times now this clock has failed over the past 10 years or so. 
> This is a stock clock with IN-18's. I have another set of these electronics 
> that has never failed, but then again, I had changed the tube board to 
> accommodate the Z566M tube. Different current demands? It has worked like a 
> charm for years now. The failure with the IN-8 clock this time was a leaky 
> C6. In the past the inductor has failed, but usually its one of the 
> electrolytics in the Pwr supply stage. It's become kind of a ritual where 
> every 2-3 years I have to pull the clock apart and play detective and figure 
> out what's wrong after its starts blowing fuses. Kind of fun now, actually! 
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