Dummies guide to building a 120watt 140 volt power supply to drive IN-9 Nixie tubes.

[fireant007]

As per the subject I am trying to drive a lot of these tubes.
I am the dummy and need a guide !

I have been having fun with just running a few of them and they take about 12mA's per tube fully lit.

Here is a Russian sheet showing various circuit arrangements.

My requirements are that the power supply be current regulated. I also want it to be a universal power supply.
ie: it should run on 110Vac or 240Vac ... switched or automatic.

First my approache was building a flyback style circuit using the ST L6563.
The trouble with that approach is that the output voltage is 400Vdc which means I will have to build a resistive voltage divider to get rid of the extra voltage which will be a waste and will just turn it into a heater.

Try as I might I can see NO way to get the voltage down to 140Vdc using this chip using 240vAC as the input. (kind of obvious really as it is a step UP circuit ! )

Coming at it from another angle was to go all AC and just rectify the voltage at the actual tubes themselves.
This approach is problematic for me as I can see no practical way to regulate the AC coming from the wall socket.
And .. thus onto the tubes.

Someone suggested a ELECTROPHORESIS power supply. So I was looking around for circuits for them.

What I really NEED is half a clue on which way to go with this !

Here is the Russian data sheet.

Please save me from sitting at my computer researching for weeks instead of at my soldering bench building for months !!!

 

[spec]

Hi fire,

Welcome to ETO

Just a few points:

(1) It would b a great help if you could translate the Russian data sheet above for us.
(2) I am assuming that the tubes you have are gas ionizing diodes with a striking voltage and running ionizing voltage. These are generally know as cold cathode voltage regulator tubes (valves).
(3) As the deign of your power supply would depend critically on the ionizing voltage and if cant be derived from the data sheet, could you measure it and post the value on ETO.

spec

PLEASE NOTE THAT DANGEROUS VOLTAGES ARE INVOLVED WITH POWERING THESE TUBES

Links
https://en.wikipedia.org/wiki/Voltage-regulator_tube

 

[fireant007]

Hey .. thanks for the welcome and the answer.
Appreciated.


Here is a "translated" version ?

I don't speak Russian unfortunately.
But .. I can tell you from the data sheet by guessing, inference and experimenting.

B in Russian = V in English.....

Line 1 is the kandela out. 40/M2
Line 2 is the viewing angle 50 degrees
Line 3 is the maximum voltage that can be applied. 250
Line 4 is the ionizing voltage. 140V
Line 5 is the maintenance voltage. 70V
Line 6 is the maximum milliamps at which the bar is fully lit. 12mA
Line 7 is the bar length lit minimum and maximum. 20-97mm
Line 8 Linearity +/- 4%
Line 9 is possibly the lifetime of the tube ? Although the 2 data sheets seem to disagree.

 

[spec]

Hey .. thanks for the welcome and the answer.
Appreciated.


Here is a "translated" version ?

View attachment 98277
I don't speak Russian unfortunately.
But .. I can tell you from the data sheet by guessing, inference and experimenting.

B in Russian = V in English.....

Line 1 is the kandela out. 40/M2
Line 2 is the viewing angle 50 degrees
Line 3 is the maximum voltage that can be applied. 250
Line 4 is the ionizing voltage. 140V
Line 5 is the maintenance voltage. 70V
Line 6 is the maximum milliamps at which the bar is fully lit. 12mA
Line 7 is the bar length lit minimum and maximum. 20-97mm
Line 8 Linearity +/- 4%
Line 9 is possibly the lifetime of the tube ? Although the 2 data sheets seem to disagree.

Hi fire,
No sweat
The data you have supplied, and so quickly, is most helpful. I wish all those asking questions on ETO were so good.

I will give a suitable power supply some thought.

Cheers

spec

 

[fireant007]

Oh.. yeah .. I want to have some fun allright ! ... bigger fun than this ... hence I want to run about 70 or 80 or maybe even 100 of them.
All at the full 12mA

No ... these tubes are bar graph displays.

See here.

 

[JimB]

Just one little point about terminology, these are not Nixie tubes.

Nixie tubes display numbers 0 to 9, and were the predecessor of 7 segment LED displays.

These are just simple neon indicator tubes.
As inferred already, they are used sometimes as voltage stabilising devices.

JimB

 

[fireant007]

No .. they are not nixie's or numatrons or dekatrons... nixie is just a common search word people use to find them on ebay etc.
Try just searching for IN-9 and see what you get !

It is interesting that you say they are sometimes used as voltage stabilizers.

This would mean that I would not need a regulated supply ?

I could just run a 1 or 2 kva custom 140Vac transformer and rectify at the anode ?

edit: .. 1 kva might light a few more than I need !

 

[spec]

Just a link for info:
https://www.tubes-store.com/product_info.php?products_id=307

https://www.instructables.com/id/Nixie-Tube-Music-Visualizer/

 

[spec]

No .. they are not nixie's or numatrons or dekatrons... nixie is just a common search word people use to find them on ebay etc.
Try just searching for IN-9 and see what you get !

Funnily enough I just did what you said as you posted.
It's OK I understand the purpose of the 1N-9 now. I hadn't realized that they are relatively long and thin and are for display purposed rather than voltage stabilization.
spec

 

[fireant007]

Yar... they be hard to find just using IN-9
I have seen all the nixie sites on the net.
I have hundreds of them. Nixies .. that is ... as well as IN-9's
Love em.... nixies are easy.
Decatrons are tricky ..... very tricky some of them.

One of the best sites for information is.
https://threeneurons.wordpress.com/

That guy has my money and has created a monster !

This guys .. is even more obsessed than me.
He created a working replica of a genuine cold war era clock.

Zero electronics in it.... would be easy with electronics .. but I am guessing he is afraid of the EMP when the bomb drops !

 

[spec]

Hi again fire.
A few more questions:

(1) Am I right in saying that you want to make a bar graph display with up to 100 of 1N9 discharge tubes (1.2A max)
(2) If so are you going to design the current modulators to make the tubes dance or would you like ETO to suggest a suitable circuit.
(3) If the answer to (2) above is yes, what drive signal input would you like for each tube.
(4) Is operation at 240V essential of would 110V only be OK (this would make the PSU circuit very simple)

My missus has been unreasonable and wants me to go shopping, but I should be back on air in around in around 5 hours time (7pm GMT). I have a pretty good idea for a suitable design- interesting project. I hope we can see a demo when it is finished.

spec

 

[JimB]

Ah!

I should have looked a bit closer at the diagram.
These things are 140mm long, far bigger than the ones which I was thinking about.

I think that I can safely say that I have never seen anything like this before.

JimB

 

[Les Jones]

How about one of these transformers. they have two 115 volt primaries and two 55 volt secondaries So you could connect the primaries in series or parallel depending weather you wanted to use it from 115 or 230 volts. The two 55v secondaries in series would give 110 volts AC that when rectified and smoothed would be about 155 volts DC (110 x 1.414).

Les.

 

[AnalogKid]

I agree. An auto- or manual-ranging linear power supply would be much easier to develop. At 140 Vdc output, 120 W is less than 1 A. With a 1:1 transformer, peak AC is around 160 V so the regulator would dissipate round 20 W, not hard to deal with. Follow that with constant current circuits to limit the current in each output branch to 10 mA. Each current limiter would dissipate 1.4 W into a dead short, less into a working channel. Lotsa parts, but simple circuits.

ak

 

[fireant007]

Hi again fire.
A few more questions:

(1) Am I right in saying that you want to make a bar graph display with up to 100 of 1N9 discharge tubes (1.2A max)
(2) If so are you going to design the current modulators to make the tubes dance or would you like ETO to suggest a suitable circuit.
(3) If the answer to (2) above is yes, what drive signal input would you like for each tube.
(4) Is operation at 240V essential of would 110V only be OK (this would make the PSU circuit very simple)

My missus has been unreasonable and wants me to go shopping, but I should be back on air in around in around 5 hours time (7pm GMT). I have a pretty good idea for a suitable design- interesting project. I hope we can see a demo when it is finished.

spec

Soz for the late reply I am GMT +8 so gotta sleep sometimes
1. = correct. But not a vu meter. something else that I want to surprise everyone with.
2. also correct the current modulation is my end and would be done on the cathode to ground via a transistor via an arduino. Yes I know I can't drive 100 with just an arduino .. but I have a shift register for that.
3. I have uploaded a file on how to control these things.
4. I need to be able to drive it via 110 or 240... I don't want to deprive half the world of all the fun !!.

Your missus HAS been very unreasonable... unless she is taking you shopping to RS componants !

You will indeed see a demo when this is finished !..... I hope to impress

 

[fireant007]

How about one of these transformers. they have two 115 volt primaries and two 55 volt secondaries So you could connect the primaries in series or parallel depending weather you wanted to use it from 115 or 230 volts. The two 55v secondaries in series would give 110 volts AC that when rectified and smoothed would be about 155 volts DC (110 x 1.414).

Les.

Thanks Les...
Been looking for a suitable trannie for a while.
I am not the only ETO member here that has been trying this ....

https://www.electro-tech-online.com/threads/in9-nixie-tube-getting-a-full-scale.142234/

The post above is 100% correct .. you need to "exercise" these things to get them to perform properly.

I drive mine at about 15mA for a few mins at about 160VDC to get their legs stretched.
then they all display full length.
I have ZERO clue why.

Les your transformer should fit the bill !

But .. question ... do I need to regulate the anode voltage to have a stable reading or will the display drift as the mains voltage goes up and down ?

 

[fireant007]

I agree. An auto- or manual-ranging linear power supply would be much easier to develop. At 140 Vdc output, 120 W is less than 1 A. With a 1:1 transformer, peak AC is around 160 V so the regulator would dissipate round 20 W, not hard to deal with. Follow that with constant current circuits to limit the current in each output branch to 10 mA. Each current limiter would dissipate 1.4 W into a dead short, less into a working channel. Lotsa parts, but simple circuits.

ak

Simple for you sensi master .. please show me the path !

BTW .. thanks for all the input guys ... very helpful for a linear circuit challenged digital guy !

 

[fireant007]

I found this very old looking circuit.

Looks kind of like a boost circuit without any inductor ! ??

Have zero clue how it holds any specific voltage. I can't see any feedback at all ?
Looks too me like it just reduces the mains then wanders around at what ever reduced voltage it feels like.

See no way to fix a voltage with it. ?

 

[fireant007]

I like this circuit. But I also hate it ... because if I use 240Vac I can't reduce the voltage below that !
It is going to be tricky to build also .... switched mode power supplies aint my forte !

I particularly like it because is is transformerless !

 

[Les Jones]

When I first saw your post about nixie tubes and wanting about a 1 amp power supply I was puzzled. I even took my digital frequency counter apart that I built in the early 1970s to see what I used for the high voltage supply. I found that I had used an unregulated supply of about 250 volts and the current to the anode of each nixie tube was limited with a 100K resistor so the current would be about 1.8 mA. That made me wonder what you would be making with about 500 nixie tubes. I have never seen the tubes you are calling nixie tubes. I now see my suggestion for a transformer was not much help now that you have put in your location. I don't think you need a regulated power supply. If you design the cathode drive circuit as a variable constant current source rather than a variable constant voltage source then the actual anode voltage should not matter too much. I had tottaly forgotten about dekatron tubes until I saw your picture of the clock using them. When I was in my late teens (Early 1960s) I used a few of these followed by an electro mechanical counter to count pulses from a Geiger Muller tube. I hope you can find a supplier in Australia for a suitable transformer.

Les