rjr (01/05/83)
I tend to agree with the statement that tape heads probably do not
usually need demagnetizing in modern tape machines. One thought on
how they might get magnetized is that I have seen circuits in decks
where a large transient spike appears across the head when the unit
is switched out of the record mode. To me, this would be the major
cause of permanently magnetized heads. In the many years I was
professionally using tape equipment, I never used a head demagnetizer
and always just used plain drug store rubbing alcohol for cleaning
the heads, capstan, and pinch roller. The only pinch roller I ever
had to replace was in a 20 year old machine. I still have several
1950 vintage full-track Magnecorders that still have the original
pinch rollers. (The worse cause of dirty machines used to be the
old acetate-based tape)!
Bob Roehrig
...we13!rjr