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Vintage computer fun

We kicked off our home computing with an Acorn Atom. Later progressing onto a BBC 'B' them the Amiga via an Atrai XL 800.
Funny era, with lots of people coding and building computer expansion boards/I/O etc.
 
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I was in playing with the Manchester SSEM “Baby” again today and actually remembered to take a couple of pictures for a change!

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A whole 1024 bits of valve binary goodness!


I can smell the hot baking dust from here!

They don't make computers like they used to,......thank goodness!
 
Valve computers lasted longer than many people realise.

I went to service an instrumentation tape machine connected to a large analogue valve computer at a defence research establishment in 1973. The man in charge told me there were three other similar computers at various places round the country and there was no imminent replacement on the horizon. He also said that they had recently save 3Kw of heat by replacing the old metal rectifiers in the valve heater circuits with silicon rectifiers - that infers a very large number of valves.
 
Analogue computers were very well suited to ballistic simulations - one of the earliest computer games, Tennis for Two (Tennis for Two - The Original Video Game - YouTube) ran on an analogue computer that had been designed to calculate ICBM flightpaths. By the time solid-state took over from valves, analogue computing had given way to digital, and floating-point mathematics had got fast enough that digital computers could do the same calculations.

Incidentally that video title is wrong, Tennis for Two was not the first video game: that honour belongs to the UK - either a version of noughts-and-crosses called OXO that ran on the Cambridge EDSAC in 1952, or a contemporaneous, but now lost, game where the player guided two-pixel “sheep” through a moving gate.
 
Incidentally that video title is wrong, Tennis for Two was not the first video game: that honour belongs to the UK - either a version of noughts-and-crosses called OXO that ran on the Cambridge EDSAC in 1952, or a contemporaneous, but now lost, game where the player guided two-pixel “sheep” through a moving gate.

I’m pretty certain the first ‘oxo’ game was programmed on the Ferranti Mk I (the descendant of the SSEM) in Manchester, not EDSAC. We certainly take it as a win here in Manchester!
 
Analogue computers were very well suited to ballistic simulations

Yes, the gunnery computers used on Anti aircraft guns towards the end of the war were analogue, in conjunction with the Radar information they could calculate the correct bearing to aim at for an aircraft on a turning path as well as the travel time of the shell.
 
I’m pretty certain the first ‘oxo’ game was programmed on the Ferranti Mk I (the descendant of the SSEM) in Manchester, not EDSAC. We certainly take it as a win here in Manchester!

This (MENACE) was featured on QI really and shows in a physical medium, how to programme a computer to learn to not lose at noughts and crosses. Fascinating. You probably know it.

 
I’m pretty certain the first ‘oxo’ game was programmed on the Ferranti Mk I (the descendant of the SSEM) in Manchester, not EDSAC. We certainly take it as a win here in Manchester!
You are right... I had watched an interesting presentation about this about a year ago, and they gave credit to Christopher Strachey at Manchester, but it wasn’t noughts and crosses, it was a draughts game. I don’t know why that fell out of my head again, and Wikipedia still assets A.S.Douglas’s “a game of noughts and crosses” on the EDSAC. The timing of these is very close, but while Strachey’s latest possible date is Summer 1952, Douglas’s is December 1952.

The sheep-and-gates game, by Stanley Gill on the EDSAC, at around the same time as Strachey’s draughts game was intriguing, as it was much more of a “video game” than either OXO or draughts, because it had an independently moving object in it (the “sheep” pixel) that required real-time reaction from the player, but there is no hard evidence for it being implemented and running - it’s described in a paper, but that doesn’t necessarily mean it ever ran correctly... Not a surprise, I suppose, given that wasting precious computing time on making such frivolities would have been dimly received by management.

Here’s that presentation: The First Video Game - YouTube
 
Yes, the gunnery computers used on Anti aircraft guns towards the end of the war were analogue, in conjunction with the Radar information they could calculate the correct bearing to aim at for an aircraft on a turning path as well as the travel time of the shell.

Battleships had similar machines which also included things like gyroscopes to correct for the ship roll (I think they delayed the firing till the ship was flat rather than correcting for it, as you can't move 16 inch guns fast enough to cope with the roll). Here's all you need to know to operate your battleship:

 
Analogue computers were very well suited to ballistic simulations - one of the earliest computer games, Tennis for Two (Tennis for Two - The Original Video Game - YouTube) ran on an analogue computer that had been designed to calculate ICBM flightpaths. By the time solid-state took over from valves, analogue computing had given way to digital, and floating-point mathematics had got fast enough that digital computers could do the same calculations.

Incidentally that video title is wrong, Tennis for Two was not the first video game: that honour belongs to the UK - either a version of noughts-and-crosses called OXO that ran on the Cambridge EDSAC in 1952, or a contemporaneous, but now lost, game where the player guided two-pixel “sheep” through a moving gate.

My earliest experience of analogue computing was at uni. I recall it was a bleedin relief when we managed to get the required results out of the thing! But also very satisfying to demonstrate theory in action in 'classical control methods'.
I believe the Saturn 5 launch vehicle (1969) used a hybrid of digital and analogue computers, with the digital one setting targets and timings and the analogue signaling which way to wiggle the rocket motors to give the required result.
 
as you can't move 16 inch guns fast enough to cope with the roll)

Similarly the turret movement, we had an ex navy engineer in our office who told us of the woes of his ship in which the turret motors were not up to the job and burn out for a past time!
 
Similarly the turret movement, we had an ex navy engineer in our office who told us of the woes of his ship in which the turret motors were not up to the job and burn out for a past time!

I expect that if they`d looked in the tool kit there would have been a handle for manual operation. Or they could have just turmed the boat so the guns pointed in the right direction.

There`s usually a work round.
 
Battleships had similar machines which also included things like gyroscopes to correct for the ship roll (I think they delayed the firing till the ship was flat rather than correcting for it, as you can't move 16 inch guns fast enough to cope with the roll). Here's all you need to know to operate your battleship:

The B29 had remote controlled guns and a fire control system, 5 sighting stations for 4 turrets, each sight had a computer and could control two or more turrets.
 
I expect that if they`d looked in the tool kit there would have been a handle for manual operation. Or they could have just turmed the boat so the guns pointed in the right direction.

There`s usually a work round.

I cannot say for sure, and John,(ex navy electrical engineer) passed away many years ago so I can't ask him. I think the point he was trying to make was that the war machine he had worked on and maintained during the 50's and 60's didn't work reliably as intended. Actually, despite being a very polite man he was a lot ruder about it than that.

But I suspect that hand wind might not be viable. This is perhaps an extreme example but Wikipedia identifies that a three gun turret of the WWII Yamato each weighed around 2,500 tonnes. I'm not sure that I can get my head around that.
 
But I suspect that hand wind might not be viable. This is perhaps an extreme example but Wikipedia identifies that a three gun turret of the WWII Yamato each weighed around 2,500 tonnes. I'm not sure that I can get my head around that.

That`s about the weight of an entire Leander class frigate.
 


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