Early Programming Books

[Paul Koning]

> On Jun 21, 2021, at 1:53 PM, Van Snyder via cctalk <cctalk at classiccmp.org> wrote:
> 
> On Mon, 2021-06-21 at 06:02 -0700, jim stephens via cctalk wrote:
>> That 1620 would have been a fantastic addition to their running 
>> display.  Much easier to work on than what it sounds like the 1401 is.  
>> And with a duplicate backup.
> 
> CHM has a 1620 that was running for a while. IIRC, somebody told me
> that the reason it stopped running was a damaged fan in the core
> memory. Nobody explained why that was a real problem.

Core memory is fairly sensitive to temperature.  In the case of the 1620, there is a heating system that brings the core memory box up to its operating temperature, which is why it takes several minutes after you turn on power before the machine will run.

Possibly the fan problem meant the temperature control system was no longer adequate.

	paul