Epson PX-8 Technical Manual page 162

REV.-A
Observed microcassette tape playback waveforms - AZIMUTH tape
(Top) Measured at IC3, pin ....................... 5 mV jDIV
(Second from top) Measured at the
center of R26 and
R27 ............................. 20 mV /DIV
(Second from bottom) Measured at IC4,
pin 6 ..................... 50 mV /DIV
500,uSjDIV
(Bottom) Measured at IC4, pin 5. AC
mode ......................................... 2 V /DIV
Fig. 3-24
The top three are since waves. The bottom signal is almost a square wave, due to a peak detec-
tion by a diode inserted across pins 1 and 2 of IC4.
Observed noise filter (phase compensation) circuit signal waveforms AZIMUTH - tape
(Top) Measured at IC3, pin
(Second from top) Measured at the
center of R26 and
R27.
(Second from bottom) Measured at IC4,
pin 6.
(Bottom) Measured at IC4, pin 5.
AC mode
200 mVjDIV
50,uS/DIV
3-16
Fig. 3-25
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