Commodore CBM - Cleaning and Demagnetizing the Tape Head; PET Cassette Tape Head

CLEANING AND DEMAGNETIZING THE TAPE HEAD
The tape deck head area of the PET cassette can be seen by opening the
cassette
window with power OFF and depressing the PLAY key. This juts the tape
head
mount out past the bottom edge of the cassette window area. where it is
marginally reachable for maintenance. The tape head is shown in Figure 2-9.
Erase Head
Head Gap
Area Capstan
Pinch Roller
•
Figure 2-9. PET Cassette Tape Head
The tape head is the portion of the cassette unit that the magnetic tape
contacts
when vou record or play back. The oxide coating on the magnetic
tape gradually deposits a film
on the tape head and surrounding area: this
deposit must be removed periodically by cleaning the tape head to assure
reliable operation of the cassette unit.
To c1ean the tape head. use a cotton
swab soaked with denatured ethanol. Clean both heads and also the capstan and
pinch raller
(see Figure 2-9). Allow the area to dry completely before closing the
cover.
The tape head also needs to be demagnetized periodically. The tape
heads gradually become magnetized through use. This affects recording fidelity
and eventually causes recording errors. To demagnetize the tape heads. vou will
need a tape head demagnetizer (see Figure 2-10); this is an inexpensive unit that
can be purchased at most audio equipment stores.
To demagnetize the tape heads. have the cassette
window open and the
PLAY key depressed. To use the demagnetizer. have it at least
two feet away from
the
PET before plugging in the demagnetizer (the PET shou Id be OFF). SLOWLY
bring the demagnetizer towards the
PET until it contacts the head surface;
carefully move
it around on one head surface. then the other head surface. then
ail metal surfaces
that are directly adjacent to the heads. SLOWLY move the
demagnetizer back at least
two feet before unplugging it.
CAUTION: Keep your pre-recorded cassette tapes away from the demag-
netizer. The demagnetizer
is an effective tape eraser. Keep it at least five feet
away fram any pre-recorded cassettes.
The more vou use your PET. the more often it will need to have the tape
heads cleaned and demagnetized.
Do it at least once a month - more often if
vou are experiencing load problems or tape degradation.
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