This is a vintage digital display. It's called an inline digital display and it was made by Counting Instruments Limited and this has a series of Tung and lamps and the Tung and lamps. If I shine a light down the end, you'll see each one has a matching lens including the red and green filter at the top and the numbers 0 to 9. These are also used in other applications like gaming equipment with symbols, but in the digital form.

It would have been used in things like counting, weighing, and potentially in in Industrial Automation equipment where you'd have a row of these behind the panel and they'd project the number onto the front. but it's not bright. It kind of needs a shield to make it visible, but that's possibly in this case down to the fact it's using 24 volt lamps. Let me show you it lit so you can see what it looks like one moment please.

So here it is lit up and I Have to say the camera is doing it favors. It does not look as bright as that here, even in a very dark room. It's a very low intense display and at the moment I've got the the green background plus the digit 9 but I can run the contacts along here and it will go 3, 6, 9 and if we run down the other side 1, 4, and seven, the seven seems way off and zero. but um, that's basically it.

Now let's take it apart and take a look inside one moment please and watch your eyes. the light is coming back, The light is back. Let's zoom in a little bit and we'll begin the tear down. I'll show you what's inside here.

so for maintenance purposes, you could take these two screws out at the back and drop the whole lighting assembly off it with its little spacers. So that's one screw and two screw. and I Have to say these things were available in a multitude of voltages. This one uses 24 volt lamps with 100 milliamp current, so 2.4 wats.

That seems quite a lot. but because the 24 volt lamps have a big huge filament, uh, it's not optimal for this because it is needs a really pinpoint source. so very little of the light just literally. The stuff that shines out the end here is a bit that actually illuminates the display, which indicates why it's so dim.

If on the other hand, I was to pop that filter over and stuff an LED flashlight up the other end, it should be quite bright. perhaps? Oh yeah, see LEDs would be so much brighter. They're daylight visible. That would be much better, but they didn't have LEDs back then.

Um, so now we're taking the lamp housing out with its uh, lamps and insulated separators here. Although they're all kind of connect together, it might just been I wonder if it was just a light barrier, but if we now tip this up, then the next bit that comes out scrunching noises I've had this apart already is a very heavy is this metal? Let's try and stick a magnet to it. No. I'm not sure what that is I Think it's partly to do with thermal dissipation, but it's also a mask that goes over these lamps to provide a sort of nice, tightly defined uh light guide and block the illumination from other adjacent lamps.

After that, we have a piece of glass, possibly a heat shield. Then we've got a spacer. Then we have the number plate. Now the light shines in from this side through the lenses.

cating lens I'd guess And then it has the numbers on a piece of plastic film. The film is held in place by a little copper strip that is just clicked through to hold that uh, generic film in place. Then there's a space and then the matching uh set of lenses. Then Focus that and it is curved.

H This lens set lens is also curved um, but it focuses it through the mask and and The Mask has the Colors Over the red and green. Plus, it's just basically the open points for the digit. So this, relatively speaking inside. these would be spaced about that apart inside and that's more or less it.

It's basically one lamp and the lens and the slide, and then the focusing lens and the shield. And that is how it projects each number. Very simple in a way, but also quite complex. It meant that each housing had to have 13 wires going a common wire plus the 12 for the individual lamps and it would have been a fairly High current display.

Think of it's 24 volt that 100 milliamps. it's fairly high power um for the 6. Uh5 volt l or the 6vt lamps that would potentially have been four times as much current just to get the same sort of intensity I' gas. Although having said that, the smaller filaments tend to be a little bit smaller and sharper and whiter.

uh these days. Of course, with the Uh LEDs being focused, it would have just worked so much better. But they did did what they did with what they had and back then it would have been quite a complex and sophisticated display, but that is it. Nothing else left inside.

What is inside here is some stepped layers in here, so when this is placed in, it will sit in its layer, then when you put the next layer and it sits in its layer and then the sort of I'd Guess this is a shim perhaps. And the glass, which uh, probably the shim is to stop the glass actually touching or rocking against the actual lenses. but that is it. Very modular, very logical, very sensible.

There were lots of uh exotic displays back then. Uh, used for uh automated equipment and factories just because. Uh, it was useful to have these s of digital displays. Um, but they had to implement with what they had.

Very interesting, very neat. well worth taking apart.