J
John Woodgate
- Jan 1, 1970
- 0
I read in sci.electronics.design that Barry Lennox
[email protected]>) about 'Ways to *REALLY* erase a hard drive?', on Sat, 12
Feb 2005:
I made a magnetizer for model railway motor magnets that way about 50
years ago. Rectifier straight off the 240 V mains to a 20 uF cap through
10 kohms. Switch to connect the cap to a 'no-volt coil' from a motor
starter - lots of turns. Custom-made magnetic circuit (the railway nerd
provided that from his machine-shop).
Interesting that the switch current is initially zero and finally zero,
so no arcing problems, but in between, about 2 A.
[email protected]>) about 'Ways to *REALLY* erase a hard drive?', on Sat, 12
Feb 2005:
I used to use one that look a little like a microwave oven, and the
manufacturers blurb stated it used a charged cap dumped through a coil.
Never saw a schematic or got to look at it's guts however.
I made a magnetizer for model railway motor magnets that way about 50
years ago. Rectifier straight off the 240 V mains to a 20 uF cap through
10 kohms. Switch to connect the cap to a 'no-volt coil' from a motor
starter - lots of turns. Custom-made magnetic circuit (the railway nerd
provided that from his machine-shop).
Interesting that the switch current is initially zero and finally zero,
so no arcing problems, but in between, about 2 A.