Test Mode - Fostex CR200 Service Manual

Notes
(1) Use a 10 : 1 probe for the oscilloscope.
(2) All the knob positions (settings) for the oscilloscope in the adjustment procedures are for when a 10 : 1 probe is used.

Test Mode

This model has a test mode so that the adjustments and checking required for servicing can be carried out easily.
When this model is put into test mode, the keys on the front panel would work differently from normal condition.
Adjustments and checks can be carried out by operating these keys with the correct procedures. On this model, all
adjustments are carried out in test mode.
[ Setting to Test Mode ]
The way to set this model into test mode.
(1) Plug the power cord back into the AC socket.
(2) Shorten the test mode lands. (See Fig. 6.)
(3) Press the Power SW ON.
When the test mode is set correctly, the display is different from what it usually is when the power is turned on. (lights up
all FL display) If the display is still the same as usual, test mode has not been set correctly, so repeat Steps 1 Ð 3.
[ Release from Test Mode ]
Here is the procedure for releasing the test mode.
(1) Press the STOP key and stop all operations.
(2) Press the Power SW OFF.
[ Operations of the Keys in Test Mode ]
Code Key Name Function in Test Mode
DIGITAL
SYNCHRO
FINALIZE
PLAY
PAUSE
Playback laser diode ON
Focus servo closes
Spindle servo ON
Tracking servo close/open
Explanation
Lights up the laser diode by playback power.
The laser diode is lit up and the focus actuator is lowered,
then raised slowly and the focus servo is closed at the point
where the objective lens is focused on the disc.
With the player in this state, if you slightly rotate the stopped
disc by hand, you can hear the sound of focus servo. If you
can hear this sound, the focus servo is operating correctly.
If you press the key with no disc mounted, the laser diode
lights up, the focus actuator is pulled down, then the
actuator is raised and lowered three times and returned to
its original position.
Starts the spindle motor in the clockwise direction and when
the laser rotation reaches the prescribed speed (about 500
rpm at the inner periphery), set the servo in a closed loop.
Pressing this key when the focus servo and spindle servo
are operating correctly in closed loops puts the tracking
servo into a closed loop, displays the track number being
played back and the elapsed time on the front panel.
If the elapsed time is not displayed or not counted correctly,
it may be that something is out of adjustment, or that there is
some other problem.
This key is a toggle key and open/close the tracking servo
alternately. This key has no effect if no disc is mounted.
CR200
15