[sdiy] Tape head collage (pretty much not synth DIY, sorry)

[Roy J. Tellason]

On Thursday 25 November 2004 05:15 pm, Scott E. wrote:
> I have never heard of a demagnetizing tape, only tapes that "clean"
> heads. Demagnetizing involves the use of a hardware device that produces
> a magnetic field for the purpose of demagnetizing the tape head. I also
> think the best way to clean tape heads is with a cotton swab and
> denatured alcohol.

The demagnetizers I've seen that were built into tapes used a little spinning 
magnet,  driven by the mechanics that normally moved tape.  I was not 
impressed.  I *think* there may be others out there,  with external power 
connection that may be useful for a slot-fed player,  but I have no direct 
experience with these.

> The technique of demagnetizing is not complicated, but one must be
> careful, as done improperly, can actually magnetize the head even
> further. The technique is to bring the demagnitizer close to the tape
> head and move it back and forth for a few seconds, then, while the
> demagnitizer is still on, remove it from the proximity of the tape head
> slowly, moving the demagnitizer in a back and forth or circular motion.
> Drawing it straight away would be a poor technique. It should be several
> feet away from the tape head before powering it off. Also, the tape
> machine should NOT BE POWERED ON while this procedure is performed.

Yes,  the recommendations that I've seen usually specify a distance of four 
feet or more.