Sharp CE-121

19
KI 5
Ampl i f i er circu i t
Schmitt circu i t
CPU 11
Output signal from the EAR PHONE jack of the tape recorder is amplified a nd shaped in the
Schmitt circuit , to be input to the CPU II through the KiS terminal of the CPU II .
5-2. Reproduction
When recording signal "1 " is t o be rec orded , Sl 5 is turn e d l ow level and the sign al F4 (cl o ck
pulse of '..;'. 4KHz) is output during t hat per i od . When recording signal " O " i s to be r ecorded , SI 5
is turned high level and the F4 output is inhibited during t hat period , at whi c h durati o n t he
reverse s i gnal of HA (clock pulse of ::: 2KHz) is ca rried on the recording s i gnal.
Then , this signal is supplied to the MIC terminal o f the tape re c orde r vi a the modulation c ircuit
of the CE1 2 1.
Signal waveform a t t he tim e o f re c ord i ng
R e c ording signal
( F 4
11 )
F4
HA
s 15
., ~ F< " ---+ To CE121 cassette rnodulat i on c i rc ui t
Sl5 ~
Recording signal (F4 " ) generation cir c uit
a rea
ring