Technics RS-B965 Service Manual

This unit is of 3-head type, and the record head is independent of
the playback head. Also, the sound before recording can be
compared with the recorded sound by use of the monitor switch,
therefore the state of recording can be easily checked.
PLAYBACK
HEAD
REC AMP PLAYBACK
MONITOR SWITCH
“source” “tape”
POSITION POSITION
LINE INPUT LINE OUTPUT
JACK (REC) JACK (Playback)
RS-B965
The recording-equalizer amplifier is an amplifier for supplying (to
the head) the current necessary for recording. Usually, loads such
as the recording head and bias trap circuitry (circuitry for control of
the bias current) would be applied to the output of this amplifier,
with the result that complex changes of the current phase occur,
causing distortion of the recording signal.
The recording-equalizer amplifier used in this unit, however, is a
linear magne-field class AA amplifier that.is a combination of class
A voltage-controi amplifier circuitry and current-drive amplifier
circuitry. (See the figure below.) As a result, a current flow that is
equivalent to the current flowing in the pure resistance of the
current-drive amplifier can be supplied to the recording head.
Consequently, a magnetic field that corresponds to the input
signals is produced at the head and is recorded on the tape, which
means that recorded sounds are faithful to the original sound
source, without fluctuations of the current phase.
CLASS A VOLTAGE CURRENT DRIVE AMP
CONTROL AMP (V-I CONV.)
INPUT
@ Pure resistance
@ Current flowing through the current-drive amplifier's pure
resistance and current flowing through the recording head
become equivaient.

Technics RS-B965 Specifications

General

Brand	Technics
Model	RS-B965
Category	Cassette Player
Language	English