Elmo ST-1200 - Magnetic recording cannot be effected; Recording level is low; Output sound is low during optical recorded film reproduction; Tone color is inferior during optical recorded film reproduction

SOUND (Conttd)
Case
Magnetic
recording
cannot be
effected
Recording
level is low
Point
Recording
knob assy
(P7-k)
AMP assy
(P7-j)
AMP assy
(P7-j)
step
Check the breakage of Recording knob assy
by a tester.
Check Sound head whether the adequate
bias voltage has been effected.
If not, replace AMP assy.
*Bias voltage:
Single recording •• 30-50V A.C.
Double recording •• 25-30V A.C.
Check the breakage of Tr3 in AMP assy to
find out the damage of high frequency
circuit in AMP assy.
If so, replace AMP assy.
Check the bias voltage of Sound head to
find out under-bias current.
If so, replace AMP assy.
Remark
Sound
head
(p5-56)
Head presser
(p5-51)
Film
If Sound head has been exhausted or broken, P-18
replace Sound head.
If the film cannot be held in parallel P-18
with Head presser and Sound head, adjust
the position of Head presser holder assy.
If the sound track of film has been
exhausted, replace film.
Output sound
is low during
optical
recorded film
reproduction
Exciter lamp
(p5-68)
Sound lens
(P5-81)
Silicon photo
diode (P5-77)
AMP assy
(P7-j)
Film
Adjust the position of Exciter lamp if it
has been distorted.
Adjust the angle and position of Sound
lens if it has been distorted.
If Sound lens has been stained, replace.
Check the breakage of Silicon photo diode
and if so, replace.
Check the output voltages on Circuit plate
in comparison with the voltage checking
points on AMP circuit plate and if the
unusual voltage would be measured, replace
AMP assy.
Recording level of the film loaded is low.
- to be continued -
-27-
P-17
P-17
P-17
P-34