Old Tech thread

[Danny McG]

Back in mid seventies I was a trainee in a UK coalmine. In one area of older workings there was a row of lights giving off a strange blue glow.
As far as I recall each light had an enclosed turbine/dynamo that was powered by compressed air.
I remember some old collier saying they'd been operating since the fifties in that area.

I've googled and you can still get compressed air lamps but these ones are hand held for inspection work inside oil tanks etc, the ones I saw were large and permanently mounted.

Just another bit of forgotten technology. No doubt the manufacturer has long since gone - very little coalmining now

 

[Danny McG]

Drat! Meant to put this thread in Technology forum, not science and nature

 

[The Judge]

Now moved.

 

[Foxbat]

I remember around the mid-seventies, being lectured on fluidics and its logic applications. It was going to change the world. You never hear about it now but, according to wiki, it's still being used in some areas like thrust vectoring.
Fluidics - Wikipedia

 

[Danny McG]

Wasn't fluidics one of the key reasons they developed the new (in those days) trade of 'instrument mechanics'?

 

[Foxbat]

Wasn't fluidics one of the key reasons they developed the new (in those days) trade of 'instrument mechanics'?

Funnily enough, I started my working life as an Instrument Mechanic (but ended it in Health Physics in the Nuclear industry)

 

[Vertigo]

Your initial post had me googling compressed air lamps (fascinating) and that led on to Trompe water powered air compressors an equally fascinating bit of technology dating back I believe to the 16C that produces compressed air with no moving parts!

 

[Edward M. Grant]

I went to the Science Museum in London a few years ago for the first time in decades, and was amused by the fluid computer for economic forecasting. From what I remember, you adjusted the liquid levels at the inputs and they went through a bunch of pipes that eventually resulted in the output levels changing.

Probably explains a lot about British economic policy in the mid-20th century.

Edit: actually, I see it's mentioned in the Fluidics Wikipedia article linked up above.

 

[Caledfwlch]

What amazes me with British Coal mines, is they often don't appear to have accurate maps! Not in terms of how what is below relates to the actual surface. I spent a few years living in Stainforth, North of Doncaster, the village which is home to the Hatfield Main, and that lack of knowledge was a bit of a worry with all the house building going on, as they knew the tunnels went all over the place, but couldn't relate it to the surface, so it was entirely possible they had built homes, or would potentially be building homes above unstable ancient tunnels.

 

[Danny McG]

Thought it might be interesting to have a thread about tech from 'days of yore'

To start, here's a memo watch from 1984.

 

[Dave]

And here, thanks to Marconi's Wireless Telegraph Company, is the latest amazing wonder of directional wireless, which could allow London Croydon pilots to fly in a perfectly straight line, or to land, through cloud, or even at night!!!

 

[WarriorMouse]

Hows this.
A fully functional waterproof radial dial Linesman service phone
I love dial telephones and have a few of them in good working order.
1930's Northern Electric desk style
Automatic Electric Type 50 Coffin top wall phone
Various RCAF office intercom phones(Military surplus)
1950's Northern Electric remote service phone

 

[Danny McG]

Me and my fellow mechanical craft apprentices all started buying and using these about halfway through our (1974 to 1978) apprenticeships.
The slide rules we'd all outfitted ourselves with were suddenly obsolete.
I still remember the maths lecturer (in love with his slide rule) grumpily saying " Oh yes, those are all fine and dandy, but what good are they if the batteries run out?"

File:Vintage Texas Instruments TI-30 Pocket Calculator, Red LED, Made in USA, A Very Widely Used Calculator, Price Was $24.95 in 1976 (8732557514).jpg - Wikimedia Commons

 

[Dave]

That was the first calculator I ever saw. I couldn't afford one though. I actually got some weird reverse logic calculator first, which wasn't so bad because no one else could work out how to use it (you had to sum 2 + 2 rather than 2 + 2 =) and so no one ever wanted to borrow it from me. When only half the class had a calculator you could find it going right around the whole class.

 

[Danny McG]

That was the first calculator I ever saw. I couldn't afford one though

Yeah it cost me like two weeks pay! Had to save for a few weeks to get one.
They came with a fancy wallet with two belt loops, nobody ever wore it like that.

Most of us cut the loops off because you could then cram it all into a denim jacket (required wear back in the day) side pocket

 

[farntfar]

Ah! The "were so amazingly primitive that they still though digital watches were a pretty neat idea" thread.

My first calculator was like this one.

We were all especially impressed that you could write ShELL OIL on it if you turned it upside down.
And it was no use getting used to it, because you could only use sslide rules in exams.

 

[Vladd67]

 

[Edward M. Grant]

The Sinclair calculator was (as usual for Sinclair) a triumph of cost-cutting. If I remember correctly, they did things like reduce the number of digits they calculated in operations where they weren't really required, so they could free up a few bytes of program memory to add extra math functions that competing calculators didn't include.

I'd never seen a real one until I went to the Science Museum a few years ago and they had one on display.

 

[Edward M. Grant]

BTW, here are the gory details on the Sinclair calculator programming:

Reversing Sinclair's amazing 1974 calculator hack - half the ROM of the HP-35

 

[Vladd67]