IN 9 / IN 13 bar graph tubes clock

[kay486]

Hi there, ive been wondering, how precise can  you be when you drive those tubes? Ive been thinking recently that they would make a really nice clock! Having six or seven tubes next to each other. The thing i need to know is if its possible with these tubes to have ten precisely given points. That way you could use them for clock pretty easily. You could even achieve neat effect if the transitions between every number would be smooth so the glow would simply grow.

[threeneurons]

The length of the glowing portion of these bargraph tubes is fairly proportional to the input current. I personally like the IN-13 better, on two points. (1) Lower full scale current. Only 4mA. The IN-9 is much higher. (2) it has a 3rd electrode, which usually locks the glow to one side. 10 discrete levels is very doable. 12 or 24 can be managed too. The drive circuit is very simple. On the cathode leg, insert an NPN xstr (MPSA42) with a resistor in its emitter leg. Tie the collector to the bargraph cathode. The base to an op-amp output. Connect the op-amp inverting input (-) to the node connecting the resistor to the NPN emitter (other end of the resistor to gnd). Input your signal to the non-inverting input of the op-amp. If the resistor is 680 ohms, 4mA will be achieved with an input voltage of 2.72V (= 680 x 0.004). Divide that by 10, or 272mV per level. You'll need to get a uC with a DAC output, or connect a separate DAC to the uC; either parallel, or serial.

[Jon]

On May 21, 12:35 pm, kay486 <luckyl...@gmail.com> wrote:
> Hi there, ive been wondering, how precise can  you be when you drive those
> tubes? Ive been thinking recently that they would make a really nice clock!

You mean like this one ? :) http://youtu.be/mQ1567EFCY0

This is with neon-filled IN-9. Grahame has made a similar one with
IN-13 I believe.

>The thing i need to know is
>if its possible with these tubes to have ten precisely given points

It's possible, but I think you'd need to buy a fairly big batch of
tubes, burn off the cathode poisoning that they all suffer from, and
then spend a chunk of time getting a matched set. I went through this
process for a small batch of kits of the seven segment clock, and
rejected a reasonable proportion of tubes, even though the requirement
for precise matching is not that great in my application. IN-13 are
better on all counts (third electrode stabilises the glow position;
more sensitive; less cathode poisoning in my experience), but they are
significantly dimmer than IN-9. You'll need to house the finished
clock somewhere with lowish ambient light.

If you're going to have a crack at this, then take a look at the
TLC5628 octal DAC. Simple microcontroller interface and will drive 8
tubes when used in conjunction with a simple transistor current sink
as Mike outlined in his post. You probably won't need the opamp to
drive the transistor base if you're using this chip with a
microcontroller - I manage around the Vbe drop in software.

Good luck!

Jon.

[kay486]

Thans for the info guys.  It doesent sound that complicated, i might give it a shot if i manage to find some time to do it.
The video you posted isnt actually what i ment, but indeed thats really nice use of the tubes too! What i though was to have all the tubes arranged verically (or horizontally if you wish) so that every tube would represent single digit from the time, like HH MM SS and maybe even tenths of a second. The time would be determined by the height of the glowing proportion. Do you know if anybode made something similar to this?

[H. Carl Ott]

On Tue, May 22, 2012 at 7:52 AM, kay486 <luck...@gmail.com> wrote:

>What i though was to have all the tubes arranged
> verically (or horizontally if you wish) so that every tube would represent
> single digit from the time, like HH MM SS and maybe even tenths of a second.
> The time would be determined by the height of the glowing proportion. Do you
> know if anybode made something similar to this?

Something like a nixietherm times 6?

http://www.nixiekits.eu/NixieTherm.htm

-carl

[kay486]

Exactly, or even times seven if you like almost flashing tube. Imo it would look really really nice.

[Grahame Marsh]

On 22/05/2012 15:19, kay486 wrote:
> Exactly, or even times seven if you like almost flashing tube. Imo it
> would look really really nice.
>

As mentioned by Jon, here's my 7 seg clock (inspired by Jon's clock).

http://www.sgitheach.org.uk/ss.html

I confirm all of what Jon found, the tubes require regeneration before
any stable/reproducable glow is achieved. The tubes are dim but
suitable for a dark corner somewhere.

Cheers Grahame

[kay486]

Look like it has been done already! I accidentaly found this site while looking for something. Really neat design, its worth checking out: http://www.bigshed.com/nixie/bargraph/

[Dennis]

I like the concept and it makes me want to give it a whirl. He's done a lot of work on the proto types. Any body know who's project this is? Maybe I missed it in there some where.

---

From: kay486 <luck...@gmail.com>
To: neoni...@googlegroups.com
Sent: Sunday, April 7, 2013 1:55 AM
Subject: [neonixie-l] Re: IN 9 / IN 13 bar graph tubes clock

Look like it has been done already! I accidentaly found this site while looking for something. Really neat design, its worth checking out: http://www.bigshed.com/nixie/bargraph/

On Monday, 21 May 2012 12:35:54 UTC+1, kay486 wrote:

Hi there, ive been wondering, how precise can  you be when you drive those tubes? Ive been thinking recently that they would make a really nice clock! Having six or seven tubes next to each other. The thing i need to know is if its possible with these tubes to have ten precisely given points. That way you could use them for clock pretty easily. You could even achieve neat effect if the transitions between every number would be smooth so the glow would simply grow.

--
You received this message because you are subscribed to the Google Groups "neonixie-l" group.
To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com.
To post to this group, send an email to neoni...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/vDSj0uKS9WIJ.
For more options, visit https://groups.google.com/groups/opt_out.
 
 

[kay486]

Here we go : http://www.ebay.com/itm/NIXIE-IN13-Desk-Clock-Rare-Russian-Tubes-Mulicolor-Led-Backlight-/221261054710 looks like somebody made it.

On Monday, 21 May 2012 12:35:54 UTC+1, kay486 wrote:

[AlexTsekenis]

Hi kay,

 

We have been able to achieve a precision of 1.5mm - 2mm (depending on how you define the boundary of the glow) with the IN-13 tube and after taking several measures: binning, cathodic sputtering and dual-region transfer function compensation. The length of the main cathode is 120mm so that's better than 0.02%. We have found several tubes in say a lot of 100 are 'gassy' and notably change characteristics even within a week. We still need to try baking them.

 

Regards,

Alex

[AlexTsekenis]

Minor correction to previous post:

2% not 0.02 %. That would have been quite a miracle.

 

Alex.

[H. Carl Ott]

After doing a couple of designs with in-9 and in-13s,  I consider 2% pretty miraculous.

 Nice work.

carl
--------------------------------------------------------
Henry Carl Ott   N2RVQ    hcar...@gmail.com

--

You received this message because you are subscribed to the Google Groups "neonixie-l" group.
To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com.
To post to this group, send an email to neoni...@googlegroups.com.

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/45953d1e-f449-49e8-8654-9961286eefff%40googlegroups.com.