Publicidad
1.
Tune selecting method
. Tune select
circuit
LED
Phototransistor
Voltage
fotlower
Negative
,
pulse
1
v
Tune select
circuit
Positive
pulse
——-
>
circuit
Inverter
QL-G90B
L-E50B
L-E30B
AL-E77BK
AL-E77BK
of the gaps between tunes (the numbers of pulse in the
rotary encoder) are stored in the microprocessor.
In programmed playback, the microprocessor commands
the lowering of the tonearm at the designated gap posi-
tions (designated pulse count values) and lifts it up at
the end of the designated tune.
Detected output
Com-
parator
Delay
Fig. 1
In the delay circuit, the signal is separated into its leading
and
trailing edges
before
being
amplified,
then
the
positive pulse is delayed and the negative pulse is in-
verted before being added.
This circuit is also used in the previous model QL-E55;
refer to the ''Techanical
Explanation'
in its Service
Manual (No. 11011).
Cartridge and tune
select sensor
Microprotessor
used
MB88401M-292K
Separate type
MB88401M-277K
|
or
MB88401i-304K
Integrated and fixed type
| MB88401lN-304K
ico. 2896)
1-3
Publicidad
