Interesting findings on the internet

[EC8010]

We even used a DXC3000P camera (early CCD) for stills in our graphics area thirty years ago.

[tggzzz]

My introduction (in Jan 1996) to digital photography was somewhat unusual since it was designed to illustrate (literally!) the characteristics of digital photography. It was a panoramic photo of the Golden Gate bridge approaches in San Francisco.

By "unusual" I mean something I haven't seen since...

The photo was printed on one of the HP CAD printers and the height was the width of the printer, i.e. ~1m high. You could get to within 1m and still not see any pixellation. Notice I haven't mentioned the width, because I'm not sure how wide it was... Certainly it went around four walls of a medium-sized meeting room, so my best guess is ~20m wide.

It took >8 hours to print, basically overnight.

The camera was obviously custom, a slit which rotated in the same way film panoramic cameras rotate. I'm not sure of the sensor, but I guess a linear sensor taken from a photocopier.

[Zenith]

I found this:
https://goprocamerasreview.com/blog/dig ... he-market/

The first commercially available digital camera was sold by Sony in 1981 or maybe was the Dycam Model 1, released in 1990. The article seems confused about this.

I wasn't really aware of them as a product you could go out and buy, and which was fairly practical, until around 1996. I saw a couple and they were expensive and limited. There were rapid advances in sensors and flash cards. These days most people seem happy with the camera included with their mobile phone.

[tggzzz]

Most people are happy with their phone's speakers!

I played with a Kodak around 1999/2000, and found it ok for snapshots but not something I would take on holiday. Brownie rather than SLR.

[Zenith]

These days the low end digital compact camera market is much reduced. As I said, most people are happy using phones. Around 2000 they were still quite crude; low megapixels, limited features, limited storage and very often bulky. By 2010 there were point and shoot digital cameras which were far better than an Instamatic.

SLRs have their own woes.

[tggzzz]

Indeed.

I rather like my Canon Powershot 16; small/light enough to carry around (unlike SLRs!), focusses down to 1cm(!) handy for TE/PCB closeups.

[Zenith]

The one I usually use is a Nikon L25, which I rescued from being thrown away. It's small and light and I wouldn't cry too many tears if it was broken or lost. I often use it when dismantling things. Having said that, I've just looked on ebay and they are dearer than I thought.

I have others.

[BU508A]

A dancing plasma toroid:

[tggzzz]

I wonder what the frequency range is, and whether any men in black suits would appear if he used it for a long time?

Didn't realise the ordinary plasma globes emit mostly UV.

Another of his videos shows laser pointers with 27mW output; they were subsequently recalled by Amazon.
https://www.gov.uk/product-safety-alert ... -2309-0144

[BU508A]

Someone built a new variation of Nixie tubes.

This video got me wondering: has anyone ever tried to build a Nixie tube filled with xenon instead of neon? I reckon a Nixie tube that glows white would look really cool.

[Zenith]

Neon is quite cheap and does the job. There are other problems with gas discharge tubes, such as the striking voltage increasing as they age. There may be good technical reasons why neon was used. There's a difference between demonstrating the electrodes of a Nixie tube working in a vacuum chamber with krypton and producing a reliable Nixie tube with a useful service life.

Other noble gases were used in advertising signs, but the power supply problems would be different from those for a gas filled regulator or Nixie tube. Possibly, when neon Nixie tubes were established, and there were even 7400 ICs for driving them, there was no incentive to create something else with a different set of voltages needed.

Xenon only exists in very small amounts in air. It is very expensive, although not much would be used in a Nixie tube. In recent years it's featured in various things such as flash tubes and even incandescent torch bulbs where its high atomic weight is superior to krypton in suppressing evaporation of the filament. It could be that up to the 70s when Nixie tubes were in production, xenon was even more expensive relative to neon.

I am something of a Philistine in this respect. I have a few bits of TE that use Nixie tubes, but I don't think they are cool and I can't see the fascination with building Nixie tube clocks.

[Zenith]

Another of his videos shows laser pointers with 27mW output; they were subsequently recalled by Amazon.
https://www.gov.uk/product-safety-alert ... -2309-0144

There was a company called J M Bull which used to advertise in Practical Electronics etc and sold electrical rather than electronic things, and started to stray into the weird and wonderful. At one time they were selling reels of missile guidance wire. They bought a lot of range finding lasers which were surplus spares for Chieftain tanks and were rated at 3W or something. The kind of thing you could use to set fire to the curtains of the house across the road. They received a communication saying these were scheduled for destruction and had found their way to auction by mistake and would they please return them. They said they'd bought them in good faith and were going to sell them to the public, which they did. I don't believe there was any legislation to stop them.

[tggzzz]

I am something of a Philistine in this respect. I have a few bits of TE that use Nixie tubes, but I don't think they are cool and I can't see the fascination with building Nixie tube clocks.

They look different, and have a k3wl vintage feel to them. Given the vast number of "invisible" modern LED/LCD/VFD clocks, it is a distinguishing feature.

Given glass and voltages, I always wonder how they make this kind of thing finger safe

[Zenith]

Given glass and voltages, I always wonder how they make this kind of thing finger safe

Given there are hi-fi amplifiers with KT66s proudly on display, with 350V from a low impedance supply on the anodes, I don't see that the Nixie clock guys are sailing that close to the wind.

[EC8010]

Nixie tube clocks are an adult toy (if I can say that without misinterpretation). As such, we don't need to worry about their safety. I'd happily have one. Especially as they're easily readable. I'd happily give the one in the picture house space if I could find one just like it.

I have a story about KT66... While I was at university, a friend was home for Christmas and accidentally knocked a decanter of port on a shelf. It fell onto his dad's (powered) Quad II power amplifiers, breaking the decanter and releasing the port, which touched the (hot) KT66 envelopes, so they shattered. Oh, and the carpet was off-white. So... He had to clean the carpet, get the (sticky) port out of the amplifiers, buy four KT66, decanter, and port therein. Moral: Keep drinks away from valves. Also, beware the casually flicked cat's tale that knocks over wine glasses.

I remember JM Bull from childhood; they advertised in Practical Wireless (hadn't yet graduated to Wireless World). I caught the bus over once. It took all day to get there and back.

[tggzzz]

Given glass and voltages, I always wonder how they make this kind of thing finger safe

Given there are hi-fi amplifiers with KT66s proudly on display, with 350V from a low impedance supply on the anodes, I don't see that the Nixie clock guys are sailing that close to the wind.

Two wrongs don't make a right!

[EC8010]

Technically there aren't two independent barriers between you and the high voltage. But nobody owning a valve amplifier is going to hide that lovely glow; it appeals to something primitive.

[tggzzz]

Nixie tube clocks are an adult toy (if I can say that without misinterpretation). As such, we don't need to worry about their safety. I'd happily have one. Especially as they're easily readable.

A house that never has kids or pets is a sorry place.

I have a story about KT66... While I was at university, a friend was home for Christmas and accidentally knocked a decanter of port on a shelf. It fell onto his dad's (powered) Quad II power amplifiers, breaking the decanter and releasing the port, which touched the (hot) KT66 envelopes, so they shattered. Oh, and the carpet was off-white. So... He had to clean the carpet, get the (sticky) port out of the amplifiers, buy four KT66, decanter, and port therein. Moral: Keep drinks away from valves. Also, beware the casually flicked cat's tale that knocks over wine glasses.

My university students' union had a cinema and projector and fire escape that was regularly used even when there wasn't a fire. The fire escape had open stairs and, underneath the bottom, a large glowing glass envelope protected by some steel mesh.

Naturally I asked what was, and was told a mercury arc rectifier. I remember this blue colour, but not the bits sticking out at the base.



Doubt it would pass muster nowadays; surprised it did then!

[EC8010]

In 1983, BBC Rampisham was about to be refurbished, replacing its 1930's HF senders with silicon upstarts. Each sender had an accompanying three-phase mercury rectifier just like in the picture. While I was in the transmitter hall all hell broke loose. Clanging bells, purple flashes from the rectifiers, green flashes from the HF valves. The farmers were burning their stubble and the soot shorted the (open) aerial feeders.

[Cubdriver]

Given glass and voltages, I always wonder how they make this kind of thing finger safe

Given there are hi-fi amplifiers with KT66s proudly on display, with 350V from a low impedance supply on the anodes, I don't see that the Nixie clock guys are sailing that close to the wind.

Two wrongs don't make a right!

But three lefts do!!

-Pat

[BU508A]

Nixie tube clocks are an adult toy (if I can say that without misinterpretation). As such, we don't need to worry about their safety. I'd happily have one. Especially as they're easily readable. I'd happily give the one in the picture house space if I could find one just like it.

You could get one from Dailbor Farny:
https://www.daliborfarny.com/eshop/

He has also his own YT channel:
https://www.youtube.com/@daliborfarny/videos

[EC8010]

Blimus! Did I read those prices right? Fahsands a Euro! I was thinking of a couple of hundred.

[tggzzz]

Blimus! Did I read those prices right? Fahsands a Euro! I was thinking of a couple of hundred.

Art sufficiently good to be a talking point attracts premium prices.

Better that than a gold plated mains plug.

[Zenith]

Given glass and voltages, I always wonder how they make this kind of thing finger safe

Given there are hi-fi amplifiers with KT66s proudly on display, with 350V from a low impedance supply on the anodes, I don't see that the Nixie clock guys are sailing that close to the wind.

Two wrongs don't make a right!

A sanctimonious response in my view. I've never heard that people were dropping like flies, because dangerously exposed power valves or Nixie tubes were a national scandal. Are there any documented instances of electrocution by that means?

Nonetheless, I've always been uneasy about valves being unprotected and thought it was asking for trouble. I can see the appeal of displaying all that EL34 warmth and goodness, which has cost deep in the purse.

Some people really don't like those neon mains indicating screwdrivers. You have a neon bulb which could be effectively a short circuit for long enough to deliver a fatal shock. Then you have a limiting 220K resistor, probably a floor sweeping. Then it might have been in a toolbox in a damp garage for years and have gathered condensation. I've never heard of anyone's existence snuffed out by one.

[Zenith]

Blimus! Did I read those prices right? Fahsands a Euro! I was thinking of a couple of hundred.

Cheap considering you are buying an artistic statement. Consider Marcel Duchamp's urinal.