Teac MT-20D-IO - Page 141

4-3-9 Check of AGC Operation
(1) Articles to be used
(a) Work tape
(b) Oscilloscope
(c) 50A
(d) DC power supply (+12 V. +5 V)
"90 ips"
(2) Check and adjustment procedures
(a) Connect 50A in accordance with Item 4-2-5. and set the POWER
switch to the PSA side (it is not required to connect a check
cable C).
(b) Load the work tape on MTU.
(c) Connect the oscilloscope to TP8 on the PCBA Drive Control.
(d) Key in "A63F".
(e) Check if the waveform shown in Fig. 427 appears at TP8.
Clipped portion
TP8
LJ
t
Approx. 3 ms
Fig. 427 Check of AGC operation
(f) If any clipped portion shown in Fig. 427 does not appear. check if
the strap 51 is open and 52 is shorted on the PCBA Drive Control.
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