Teac MT-20D-IO - Page 135

4-3-8 Check and Adjustment of head alignment
(1)
Articles to be used
(a)
Conventional type screwdriver small size
(b)
Hexagonal wrench
1.5 mm
(c)
Radio
pliers
(d)
Screw lock (red)
(e) Alignment tape
(f)
Head eraser
(g)
TZ-380
(h) Oscilloscope
(i)
SOA
(j) DC power supply (+12 V, +5 V)
(2) Check and adjustment procedures
(a) Prior to the check and adjustment, initialize MTU in the following
procedure.
1 Switch over the shorting plug on the PCBA Drive Control from
strap S2 to Sl by using the radio pliers in accordance with
Fig. 336.
Remark A metal shield may be attached to the PCBA Drive Contrgl
in some issue of PCBA. In such a case, remove the metal
shield for the strap changeover.
2 Demagnetize the magnetic head using the head eraser.
3 Clean the magnetic head using TZ-380.
4 Connect SOA to MTU in accordance with Item 4-2-5, and set the
POWER switch to PSA side.
5 Connect the TP1 (PRE) of SOA to CHI of the oscilloscope.
Setting of oscilloscope: DC mode, 0.5 V/div, 1 msec/div
6 Load the alignment tape on MTU.
7 Key in "A22", and further "1", and adjust the variable
resistor R21 (Fig. 336) on the PCBA Drive Control until the
output level of the burst signal VI displayed on the
oscilloscope is within 1.3 to 2 Vpp (Fig. 425).
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