Panaplex Bar Graph displays

[Richard Scales]

Hello,

I am looking at some 'panaplex' style bar graph displays with the objective of using them as a 'seconds' indicator.

Is there anyone in the group that give me a brief explanation as to exactly how these bargraph displays 'work'?

I have looked at a post with some details here: 

https://stromrichter.org/showthread.php?tid=3993&page=8

There is a schematic and some code.

It looks like there are 5 'scanning cathodes' , a reset cathode,  an auxiliary cathode, Anode and Auxiliary Anode connections.

I have stared at the code for some time and am gaining an understanding of the required program flow but am seeking a more basic understanding of how the tubes work, how the 5 'scanning cathodes' need to be driven etc.

All pointers gleefully received - thank you.

Kind regards

Richard

[Tristan]

These appear to based on the same glow transfer principle as the Burroughs self-scan displays (almost like one fell out of the back of an SR71 that happened to be passing over the USSR). So information of driving those should be relevant the "auxiliary" anode/cathode is called "keep-alive". The number of phases can vary but the underlying method should remain the same where the "cathode groups" are sequentially pulled to ground to transfer the glow along the display. 

https://lampes-et-tubes.info/cd/Bar_Graph_Display_for_Instruments.pdf

The key part is that only one segment is lit at a time and persistence-of-vision makes is appear as a solid bar. Conceptually in terms of program flow, in the Burroughs example you update the display 70 times per second. That means you for a 100 segment display you reset the display and advance the scanning cathode each ~143uS ((1/70)/100) once you've advanced the scan to the number of bar segments that are intended to be lit you turn off the anode until the next 14.3mS frame time. At the end of the frame you reset the display (turn on the main anode and initiate the glow with the reset cathode) and start scanning again. 

Regards, Tristan

[Richard Scales]

Thank you so much - that is amazingly helpful - the mist has cleared - so in some small way it's a bit like driving a decatron! I have some code which I am trying to follow but - not knowing how the thing actually worked - it was not totally clear to me - now I understand a little more - I'm more confident of achieving something - the display I want to use has 5 phases and the code I am looking at suggests that is possible.

Thank you very much indeed.

 

- Richard

[leo oel]

you can also look at this material
guy works with IGT1-203

https://dotdisplay.blogspot.com/2017/08/igt1-203-self-scan-bar-graph-display.html

вторник, 17 июня 2025 г. в 07:39:41 UTC+3, Richard Scales: