Reviewing site

Re: Reviewing site

John K Jordan

Test upload of picture:

File must be 100 K or below, or at least I think it's still that way.

JKJ

Re: Reviewing site

Mike Brazeau

That brings back memories John. In the early 80's our company manufactured a clinical analyser that used a PDP-8, but I think we were after ferrite cores. Used to get calls from people looking for memory boards.

computer bits

John K Jordan

I was lucky to get that one for my little museum. I have paper tape and a variety of disks too.

I saw a photo once with a huge room full of women at workbenches hand-threading the beads onto wires to make these boards.

People today sometimes have a hard time visualizing the scale of memory. That board holds 4096 bits which is 512 bytes of memory. If I calculated correctly (using 1024 for K) my 64 GB mini iPad would need over 130 million of these boards.

Another board in my collection is a static memory card from my first computer, an 8 kilobyte card kit which had 1434 solder connections and cost about $250. I maxed the computer out to 56k with these cards. IICC, to equal the memory in my 64 GB iPad would have required 2 million dollars of 1975 money and a dedicated coal-fired power plant in the back yard. BTW, that computer also ran at less than one megaHz. But it was so amazing. (I learned enough from building and programming that computer to make a career and retire from it!)

We sometimes forget how digital things have progressed. :-)

JKJ

Re: Reviewing site

Geoff Whaling

Amazing machines! A PDP 8 E (?) was the first "PC" or stand alone computer I ever used in 1975 at uni. The Paper tapes were revolutionary, far better than a tray full of punch cards. Woe to any one who dropped a tray of cards or tore your paper tape! Just imagine how many trees would be left on the planet if we were stuck with punch card batch processing on a main frame that filled whole levels of buildings.