AMSTRAD PC1512 - Resolution Check; Symmetry Check; Write Protect Sensor Check; Head Cleaning

5-7
Resolution
Check
a)
Insert
a
blank
diskette.
b)
Move
the head
to Track
39,
write
1 F and 2F by
the
top
and
bottom heads,
then measure the
average
output
level.
c) The resolution is
higher than
55%,
and
calculations shall be as
follows:
2F output (mV)/1
F output (mV)
x 1 00>55%
Measuring
Conditions
Channel
1-TP1 (10mV/div)
MODE-ADD
Channel
2-TP2 (10mV/div)
Sweep-20ms/div
Trigger—
TP6
2F
average
output
level
Resolution
=
1 F average output
level
95%
or less with
TKO
55%
or more with
TK39
5-8
Symmetry
Check
a)
Insert
a blank diskette.
b)
Move the head
to track and write 1 F
by
the
top
and bottom heads.
Measuring
Conditions
Channel
1-TP5 (0.1V/div) MODE--CH1
Trigger—
INT.CH1 Sweep-0.5ms/div
Slope(+)
T
=
400 ns or less
(If
you
have
individual
spec,
this item
obey
your
spec.)
5-9
Write Protect Sensor
Check
Load and unload a diskette and check
that write protect sensing is definitely made using
Brikon.
5-10
Head Cleaning
Check for
excessive dust or oxidised magnetic iron powders on
the
load
pad
using
such a dentist's
mirror. Clean the heads
using a cloth that produces no flues or an applicator dipped in 91%
isopropyl alcohol. Clean the heads carefully
and remove accumulated dust and oxidised magnetic
iron powders. Wipe the
head using a cloth that produces no flues.
14