30 May
2007
30 May
'07
12:27 a.m.
The feature that I like is the special two-click
cursor keys;
you press a bit harder, and the cursor move a bit faster. There's
a second switch under the key, with a stronger spring, that makes
the auto-repeat run faster (just on the cursor keys).
The HP9845B has something a bit like that. Gentle pressure on a cursor
key moves the cursor one space. Harder pressure causes it to auto-repeat.
That machine uses those saturable-ferite keys I mentioned in another
message. There are 2 cores in each cursor switch, one drive loop threaded
through both of them, and separate sense loops for each core. Pressing
the key generly desaturates the first core. pressing it harder
desaturates both of them
The keybaord is electrically wired so that the second core of each cursor
key appears at the same position in the matrx as the repeat key :-)
-tony