Technics SL-Q303 Service Manual

Detection of a record
1. When the start button is pressed without putting a
record on the turntable, the drive cam rotates in the
direction of arrow @ to turn the index sub-plate in the
direction of arrow @). At that time, the index plate
moves in the same manner as the index sub-plate.
(See Fig. A)
2. The record size detection plate interlocked with the
index sub-plate rotates in the direction of arrow oe.
(See Fig. A)
3. Then, the reset lever of the size detection base, attached
to the turntable, is pushed by the record size detection
plate and moves in the direction of arrow®.
(See Fig. B)
4. When the reset lever is pushed, the record detection pins
are projected on both inside and outside.
In this case, as both detection pins are up, they do not
touch the index plate even when the turntable rotates.
(See Fig. B, C-a)
5. The index plate does not move when no record is on the
turntable (dotted line in Fig. D). Then, the turntable
rotates 3 times for detecting 3 times. (The same holds
true for record size detection.)
6. When the index plate position has been determined, the
PU fixing plate tends to move the arm, but the arm does
not move because the short drop position setting pin@
of the PU fixing plate touches the no-record detecting
part of the index plate. (See Fig. D)
Detection of 30cm record
1. The operation is the same as for record detection, but as
a record is on the turntable, both inside and outside
detection pins are down. (See Fig. C-b)
2. As the detection pins are down, only the inside detec-
tion pin is down. (See Fig. C-b)
3. The detection pin touches the index plate and pushes
it in the direction of arrow e. Then, the index plate
Position is as shown by the solid line in Fig. D.
4. When the index plate position has been determined, the
PU fixing plate moves the arm inward, but the 30cm
record detecting part of the index plate touches the drop
Position setting pin @ of the PU fixing plate, causing
the arm to drop at the position. (See Fig. D)
Be i
we 30cm record e oF >|
a. No record
30cm record
detection pin
Turntable sheet
17cm record detection
Pin
LLL Turntable
Reset lever Detection pin
b. 30cm record detection
Record
SSSSSSSSSSSSSS SSSA SAE SS pa and FSD
1, NY ( TS ES
Fig. C
Detection of 17cm record
1. In the case of 17cm record, the outside detection pin is
up and the inside pin is down. Therefore, both detec-
tion pins are down. (See Fig. C-c)
2. The detection pin touches the index plate to push it in
the direction of arrow @. In this case, the index plate
position is as shown by the broken line in Fig. D.
(As both detection pins are down, the index plate is
pushed much more than in 30cm.)
3. When the index plate has been determined, the PU fixing
plate moves the arm inward, but the 17cm record detec-
ting part of index plate touches the drop position setting
pin @ of the PU fixing plate, causing the arm to drop at
the position. (See Fig. D)
PU fixing plate
Pin@
30cm record
17cm record
Index plate
Fig.D

Technics SL-Q303 Specifications

General

Brand	Technics
Model	SL-Q303
Category	Turntable
Language	English