[sdiy] Using the VEE pin on a 405x Multiplexer

[Dave - Dendriet.nl]

I have used many of these in that manner, with a plus and minus 7.5
volts supply. This worked fine for months, but one day the
www.sonic-wargame.net machine did catch fire. Flames of 15 cm came out
of some 4051's for undisclosed reasons. This could also have been the
result of a failing IC futher down the circuit, one of many that drove
the 50 volts relays. That power might have fired back into the sonic
wargame machine.

http://www.sonic-wargame.net/photo/06%20STEIM%20Amsterdam%202006/index.php
The green print drove the relays, the middle one caught fire. The
right one is an audio switch board that has some 405x's too, and works
to this day.

Ah, I love relays. They go *clack* and running audio through them
sounds perfect. ;_; good ol times.

Dave


(Yes, I solder on top of the copper side, or else I get confused.)