"b" wrote in message
oups.com...
looked at a recently made (last 2 or 3 years i suppose) tdk d90 audio
cassette the other day and noticed there was no metal plate behind the
pressure pad - seems this omission is widespread these days- why has it
disappeared and what was its original function? something to do with
stray magnetic fields??
regards, b.

The original function of the metal plate was, as you surmised, a magnetic
screen. Usually, the plate was made into a strip which acted as a spring to
keep the pressure pad in contact with the head(s). Why it has changed, I
have no idea - cost?

S.