Kylie has since trumped me however :- I also remember toggling switches on the PDP-8 to make it perform industrial control functions, but a long time before that I built another industrial controller for Formica Ltd. This was based on the use of 'Dekatrons' (Vacuum tube 10 position counters) with 10 cathodes which would provide a voltage output depending upon where the gas discharge inside had been pulsed to. I think I used two tubes in series for a count of 100 (or maybe 20). These specific cathode voltages were combined using transistor 'AND' gates and diode 'OR' gates together with series or parallel machine switches to turn on and off motors and air cylinders appropriate for the function required at that particular part of the machine cycle.
It worked exceedingly well, this device using a program counter and hard wired logic instead of software. I wish I'd thought to patent the basic process. If there's a prize for the oldest oldie, I received my first pension payment this week. Cheers Colin C R Dillicar Colmin Associates Ph. +64 9 834-4040 [EMAIL PROTECTED] "Avast" AV checked ----- Original Message ----- From: "Phil Scadden" <[EMAIL PROTECTED]> To: "NZ Borland Developers Group - Delphi List" <[email protected]> Sent: Friday, March 24, 2006 9:27 AM Subject: RE: [DUG] You say potatoe I say.... > > Started PDP-8, > > Okay, You win. You are the oldest man here! > > Matthew - at some point I got a sharp EL5150. Its beside me still and > does all I want in a calculator. > > ---------------------------------------------------------- > Phil Scadden, Institute of Geological and Nuclear Sciences > 764 Cumberland St, Private Bag 1930, Dunedin, New Zealand > Ph +64 3 4799663, fax +64 3 477 5232 > > _______________________________________________ > Delphi mailing list > [email protected] > http://ns3.123.co.nz/mailman/listinfo/delphi > _______________________________________________ Delphi mailing list [email protected] http://ns3.123.co.nz/mailman/listinfo/delphi
