PDP8 key (Was: Text encoding Babel.

[Guy Dunphy]

At 07:23 PM 30/11/2018 -0800, you wrote:
>> Or, if you prefer, I can dig through some old posts on this list, and tell 
>> you the depths of the cuts for XX2247.  It has been widely discussed a few 
>> years back.
>
>On Mon, 25 Apr 2011, Ethan Dicks wrote:
>> 1 - 0.0155"
>> 2 - 0.0310"
>> 3 - 0.0465"
>> 4 - 0.0620"
>> 5 - 0.0775"
>> 6 - 0.093"
>> 7 - 0.1085"
>> 8 - 0.1240"

How come there are 8? The lock only has 7 pins.
Also which is pin 1 and which direction do they number?
I just assigned a start and direction randomly on my photo http://everist.org/NobLog/pics/20181104/20181124_1741.jpg

>> Meaning that the XX2247 key would have depths (in the order you
>> describe) of 5-1-7-3-7-5-7

How do you derive those? 2 x "5" and 3 x "7" but there are no such repeats in the measurements.

>
>Given the "5-1-7-3-7-5-7", a locksmith with a tubular "code cutter" can 
>make a key.  Most tubular key machines can be used to "code-cut"
>
>But, YES, a prior owner might have removed the lock at some point, and 
>deliberately rekeyed it to different cuts than it came from DEC with.
>Not likely, but possible, particularly in some college CS departments, 
>where lots of students have XX2247 keys.

They'd have to have removed the securing pin somehow, and that has never happened to these locks.

Guy