Custom magnetic field "printing"

[AnalogPackrat]

Now this is cool.  What would CJ do with such technology?

https://www.youtube.com/watch?v=IANBoybVApQ

 

[pucho812]

In the old days it would end up in "the hole" 

 

[PRR]

That's old stuff. 3M used to sell a juice so you could micro-map tape head fields.