Operation And Adjustment Of; Auto Leadin - Pioneer PL-3000/HB Service Manual

PL-3000
5. OPERATION AND ADJUSTMENT OF TURNTABLE
DRIVE MECHANISM
Feed plate
Return lever
Actuator
Microswitch A
Crank lever
Microswitch B
Rotary cam
Disengage lever __]
Short switch
PU plate screw
Selector plate
Operation plate
PU plate shaft
Lock lever
Fig. 2. Drive mechanism when stationary
5.1 AUTO LEAD IN
When the START or REPEAT button is pressed,
power is applied to the Timing motor, and the
rotary cam commences to rotate. By the time
this cam has made half a turn (commencement of
record play), the following operations will have
been completed.
1. When the cam commences to rotate, micro-
switch A is turned on to start up the DD
motor.
2. The crank lever coupled to the cam rotates the
operation plate.
3. The start lever commences to move at the same
time as the operation plate, resulting in the
lock lever engaging the PU plate shaft (see
Fig, 3-a).
4. As the cam rotates further, the lock lever
together with the start lever moves the tonearm
across to the position determined by the
selector plate.
5. The start lever stops when it meets the selector
plate (see Fig. 3-b A point).
6. Although the start lever stops, the operation
plate continues to rotate, consequently releas-
ing the lock lever from the PU plate shaft (the
lock lever being pushed out by contact with
the operation plate at point B).
. As the operation plate continues to rotate, the
tonearm elevation is lowered until the stylus
lands on the record surface (see Fig. 5).
Selector plate
Start lever
Lock lever
Fig. 3-a Fig. 3-b