This G15 is the Oldest Running Digital Computer in America [video]

88 pointsposted a year ago
by hggh

18 Comments

broswell

a year ago

At System Source, we have a large collection of software (hard copy, mag tape, paper of software for the Bendix. Many of the manuals have been scanned by our wonderful volunteers https://rbk.delosent.com/g15doc.html

bn-l

a year ago

Is anyone immature enough to giggle when they hear the name of the computer?

johnklos

a year ago

His excitement is infectious. It's hard to not feel giddy at seeing it finally run after all that hard work!

I can't wait to see the kinds of programs we can run on a machine like that, along with discussions about tricks when writing programs for serial memory computers :D

soneil

a year ago

He's been plugging away at this machine for a year and a half - the excitement is well-earned!

renw0rp

a year ago

On the topic, the oldest original running computer[1] can be found in the UK in the National Museum of Computing based in Bletchley Park (where Alan Turing and many others worked breaking German cryptography). The museum requires a separate ticket from the "main" Bletchley Park museum. It's around 1h trip from London Euston. Well worth a visit! Among other items, they have a working "Bombe" replica

[1]https://en.m.wikipedia.org/wiki/Harwell_computer

cjs_ac

a year ago

When I visited a couple of years ago, it was quietly clicking away, computing prime numbers.

tengwar2

a year ago

Not sure if it's still the case, but when I visited, they handed you a button to single-step through the program. You actually get to operate it, at some level.

404mm

a year ago

What kinds of programs were available for this machine? I’m really curious what kind of complexity was it capable of running.

dillera

a year ago

It's been said on previous YT videos - the system probally ran civil engineering calculations for building bridges and roads. They may have even been for work in Maryland (the state) where the Bendix 'lives' - at the System Source Museum outside of Baltimore MD. It's down in Texas to get fixed by Usagi.

forinti

a year ago

I'm curious about the economics of this machine.

Wikipedia says it could be rented for $1485/mo, and the average salary in 1956 was $3600 or $300/mo, so it would have to replace 5 people (engineers must have earned more), if you don't count the extra cost of software, power, and maintenance.

I remember from a book on Richard Feynman that a classroom full of bright students was about as fast as the computer the Manhattan Project got, except, of course, the computer didn't get tired.

tengwar2

a year ago

Not really a computer though - they didn't exist in the USA at the time. If I remember correctly it was a series of IBM calculating devices chained together.

rootbear

a year ago

I’ve been to the System Source Museum many times and it’s well worth the visit if you are in the area. The G15 is a fascinating system, small and compact compared to the huge mainframe-sized contemporaries of the era.

mongol

a year ago

The oldest running computer anywhere is apparently in one of the Voyager probes. Source: a video about troubleshooting one of them that was posted on HN a while ago.

doormatt

a year ago

They were only launched in 1977. I can guarantee you there are 100's of computers that are older than 1977 that are still in active use.

tengwar2

a year ago

Vastly more than hundreds. For instance I have an HP-65 (https://en.wikipedia.org/wiki/HP-65), a programmable pocket calculator from 1974. It's collectable, but not rare. It is built with similar objectives: low power numerical applications. Of course it has substantially less memory, buit then it was substantially cheaper!