IBM 1620

[Lyle Bickley]

On Thu, 27 Aug 2015 14:28:30 -0500
Ben Sinclair <ben at bensinclair.com> wrote:

> The CHM has a bit of information, and links to three other 1620's that
> they know about:
> http://www.computerhistory.org/projects/ibm_1620/ibm1620/
> 
> From what I've been reading, there may be only one operational 1620
> right now, but the CHM is also trying to restore one.

The IBM 1620 at the CHM is a running computer. There were two teams that worked on the 1620 at the CHM. The first Team got it running. Unfortunately, IBM used the wrong kind of solder on the core memory and so the wires of the core memory literally "dissolved".

Modern memory was used to replace the original core memory and an interface to a PC was created and used to emulate peripheral devices. It ran as a demo system for several years when the CHM was in its public "Visible Storage" phase. 

A second Team - of which I was a member - worked to enhance the 1620's peripheral device interfaces and ultimately create new controllers for such devices as an IBM plotter. We also were trying to come up with demos that would make the IBM 1620 interesting to the general public (and not just techies or folks who had an emotional connection with the 1620).

At the same time, the CHM was also working to complete its IBM-1401 restoration (including many pieces of Unit Record gear) - and IBM 1401, DEC PDP-1 and Babbage public demos 

Many of us on the 1620 Team were also on other restoration Teams - and As time progressed, it became clear that the IBM 1620, while a running computer, was not as demonstrable as the other systems. That - and many of us simply ran out of time working on it. So our running IBM 1620 ended up in our storage facility rather than as a public CHM demo system.

It is entirely possible that at a future date it will again become a public demonstration system..

Cheers,
Lyle

> On Thu, Aug 27, 2015 at 2:07 PM, Dave G4UGM <dave.g4ugm at gmail.com> wrote:
> >
> >  
> >> -----Original Message-----
> >> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of william
> >> degnan
> >> Sent: 27 August 2015 20:00
> >> To: General Discussion: On-Topic and Off-Topic Posts
> >> <cctalk at classiccmp.org>
> >> Subject: Re: IBM 1620
> >>
> >> How many exist on Earth at this point?  
> >
> >
> > Three or four perhaps? Rare and Valuable perhaps....
> >  
> >>
> >> On Thu, Aug 27, 2015 at 1:56 PM, ben <bfranchuk at jetnet.ab.ca> wrote:  
> >> > On 8/27/2015 2:46 AM, Kevin Tikker wrote:  
> >> >>
> >> >> Looking for an IBM 1620 to purchase. Any leads greatly appreciate.
> >> >>
> >> >> Kevin Tikker
> >> >>
> >> >>
> >> >> Sent from my iPhone  
> >> >
> >> >
> >> > Sending from a Telephone, would have worked when they were shiny and
> >> > new. Good luck Digging for one.
> >> >
> >> >  
> >>
> >>
> >>
> >> --
> >> Bill
> >> vintagecomputer.net  
> >  
> 
> 
> 



-- 
73      AF6WS
Bickley Consulting West Inc.
http://bickleywest.com

"Black holes are where God is dividing by zero"