[HECnet] long term paks

[Dave Wade]

> -----Original Message-----
> From: owner-hecnet at Update.UU.SE <owner-hecnet at Update.UU.SE> On
> Behalf Of Paul Koning
> Sent: 14 March 2020 18:27
> To: hecnet at Update.UU.SE
> Subject: Re: [HECnet] long term paks
> 
> 
> 
> > On Mar 14, 2020, at 10:26 AM, Thomas DeBellis
> <tommytimesharing at gmail.com> wrote:
> >
> > I think that's an easy case to make for hardware; sooner or later you
run
> out of vacuum tubes...
> 
> Not as soon as you might think.  They are still made.  And they can be
made
> at home, with practice.  Transistors are harder, and with VLSI you're
> dependent on the manufacturers to keep manufacturing.
> 

I demonstrate a replica of a 1948 valve computer.
The builders expected to get 5 years out of it but its now 20 years old
We don't change that many valves but we do run the heaters on half voltage
so they warm up gently
We recently bought some "new old stock"  EF50s on E-Bay for £1 each


> I remember some years ago a company that specialized in making and selling
> obsolete germanium transistors.
> 
> 	paul

Dave