[TUHS] magic, was pseudo tty history

[John Levine]

It appears that Larry McVoy <lm at mcvoy.com> said:
>On Sat, Aug 16, 2025 at 08:21:30PM -0400, Aron Insinga wrote:
>> The PDP-6 had a sign on it that said something like "This machine
>> is old and flaky so don't touch it unless you know what you are doing."

PDP-6's were flaky even when they were new, due to large circuit cards
with unreliable connectors.  I gather a standard diagnostic technique
was to tap all the cards with a rubber mallet to reseat them.  The KA-10
used much smaller and more reliable Flip Chip cards.

>Wasn't there a PDP-<something> at MIT, I think, that had a switch labeled
>"magic" and "more magic" that had wires that went nowhere but it only 
>worked when set to "more magic"?  I'm sure I have the details wrong but
>I have a pretty strong memory of that.  Anyone able to confirm?

Probably this one:

https://boingboing.net/2022/08/11/a-story-about-a-weird-magic-switch-at-mit.html