100w Light Bulbs.

[PCPaul]

You probably want to watch this then...

It's a triode being made - by hand. Very impressive craftsmanship.

[D.M. Procida]

How fantastic, thank you.

One thing I didn't notice was the stage when the tube would have been evacuated - I will have to watch it again.

Daniele

[PCPaul]

I think it's at about 11:40 - you can hear a vacuum pump running for a while, then the neck is sealed.

PS, about your .sig for the BMW Cosy Coupe - you can write EBay URLs like to make them neater.

[Andrew Gabriel]

I think it's not very clear, but it should be the period when he's heating up all the parts including induction heating of the anode (to drive off adsorbed gasses), through to making off the seal. There wasn't a getter in the valve, so I think it would go soft quite quickly in spite of this.

When I was reading Physics at UCL in 1980, there was a glass blower in the basement who made valves, lamps, tubes, etc as required by the various experiments going on in the building. I was forewarned that every few years he gave a demonstration, and it was definately not to be missed, and that was absolutely right. Started off with something basic -- a neon tube, then a light-bulb, a little cathode ray tube, and some impressive purely decorative things. Apparently, he used to get various senior staff bringing in their broken/chipped wine glasses to be repaired.

[Huge]

Actually, Perl is a programming language. Perhaps you mean "pearl"?

[Bob Eager]

I think we had one at Kent too....gone now I am sure.

Another good demo to look out for - which I did see - is someone who can do complex sugar work! Quite amazing, at a lower temperature of course...

[Frank Erskine]

,

That appears to be the crucial moment, but I've always been amazed at how the seal is made when the 'innards' of the valve are at a pretty low pressure, subject to atmospheric pressure outside, without the softened glass collapsing, i.e. the pip being sucked into the valve. Clearly there's a progressive setting process involved...

[Derek Geldard]

If you don't get with the message little John Prescot will die.

Oh. Just a minute ...

Derek

[Huge]

You/we did. In the Chemistry building. He used to do an introductory glass-blowing course. I still have the fermentation lock I made here, somewhere, I think.

[D.M. Procida]

Thanks, I knew there had to be a way!

Daniele

[Bob Eager]

I only ever did one term's labs in there. And visited to peer at the PDP-8...

It's now called the Ingram Building...

[Huge]

was Ingram?

And who's the totty in the web page?

[Bruce]

Even better, try:

way, you get directed to ebay.co.uk rather than ebay.com.

[PCPaul]

Hmm. I'm sure I tried that when I first discovered it months ago and '.co.uk' didn't work when '.com' did (and led to the same item.)

I guess they fixed it...

[Bob Eager]

Last vice-chancellor but two. It's become common to name buildings and rooms after people who've held senior posts, honorary graduates and the like....

We have the Templeman Library (first VC). Marlowe (OK, ancient person in that case) is new name for Physics. Darwin and Eliot (particularly) have rooms or buildings named aftter people; Eliot has a Lyons Room, Darwin has a Keith-Lucas House. There's even a Bob Eager Computer Suite (really!).

Dunno. Web site is down right now. Usually it's a photogenic student (well, that's what our department does).

[D.M. Procida]

David Ingram, former VC.

I bet (I hope) there aren't going to be many Sibson buildings.

No Vice-Chancellor is loved very much, but some are loved quite a bit less than others.

Daniele

[Huge]

Ahh, thanks.

I kinda guessed that.

[meow2222]

,

Apart from its more modern envelope shape, its a 19-teens to early

1920s style 4 pin direct heated bright emitter valve, so would have been soft from the start. The softness of the vacuum aided in emission

- it had no emitter coating. Unfortunately such valves had short service life.

For anyone thats curious and doesnt know, they were used with a heater pot so you could keep filament temp as low as was needed to get enough gain and emission, thus prolonging its life.

NT

[John Rumm]

Or if anything like most, its a female photogenic student, preferably from an ethnic minority. Ticks all the right PC boxes that way!

[Bruce]

Unlike your posting, then.