Panasonic RX-DS45 Service Manual page 33

RX-DS45
Mechanical Adjustment
Screws
(1) MECHANICAL ADJUSTMENT
1. Connect the oscilloscope's CH. 1 probe across
beeydeki(+) and tseyfene (V-REF) on the Servo
P.C.B.
Oscilloscope setting:
VOLT scgst ones tag eon Le tases 200 mV
SWEEP Aw.etiecsa alae sigue tes 0.5 usec
Input coupling .............. eee eee eee AC
2. Switch the player power ON, and play track 9 onthe
test disc (SZZP1056C).
3. Leave the player in Play mode and place it as shown
in the figure on the right.
4. Alternately adjust the two mechanical adjusting
screws with the 2.0 mm allen wrench (SZZP1101C)
until the RF signal amplitude variation on the oscillo-
scope is minimized.
5. After completing the adjustment, lock the mechanical
adjustments with lock paint (RZZOL01).
(2) BEST EYE (PD BALANCE) ADJUSTMENT
1. Connect the oscilloscope's CH.1 probe across
ides) (+)and peered (—) on the Servo P.C.B.
Oscilloscope setting:
MOLE 4 sien tielai inert acreied Seale Unie a 100 mV
Input coupling ........... cece eee eee AC
2. Switch the player power ON, and play the test disc
(SZZP1054C).
3. Adjust VR701 until the RF signal eye pattern ampli-
tude is maximized.
NN
ANNA ORNS
RRS HNO
Z SASL SCISZ SZ BS SZ EC SZIZ SZ
ESSE SSS MS
"Maximize the amplitude.
(3) ae GAIN ADJUSTMENT Oscilloscope setting: VOLT ..........
. Set the "FREQUENCY" dial of the servo gain ad- (both channels)
juster's to "1,000" the "RANGE" selector to "x1" SWEEP ........ 1 msec.
and the "OSC LEVEL" control to '0.15" (1 kHz, Input coupling .. AC
150 mVp-p).
2. Set the "MODE SELECTOR' to position "2", and the
"TRACKING ON/OFF" switch to "ON". ef ec
3. Play t r a c k 1 (1 kHz) on the test disc (SZZP1054C) A A If 1 A ATA 4 er
. Play track 1 | on the test disc 1 ; A | A AP '
: ODE SELECTO f
4. Change the "MODE R" switch setting from TW TVIIEN AY, LV, av
Hise ee
position "2" to "3".
5. Adjust VR704 until the green "SERVO GAIN" indica-
tor LED comes on to indicate '""GOOD".
6. Set the "MODE SELECTOR" switch from position
"3" back to "2" : \ R
Note: With the new version of the servo gain ad- RNA AAA A 1 IAI
juster, connect TP1, TP2, and TP3 to an.
\y
oscilloscope, and you will be able to perform
ATR
A \J
Uy | NAN
all adjustments while monitoring the wave- ERGs
vine
forms on the oscilloscope screen. Adjust ; ;
: "Adjust VR704 until is © .
VR704 until the signal amplitude on one chan- } unel@equals @)
nel becomes identical to that on the other, as
shown at right. This adjustment procedure
also applies with an oscilloscope and audio-
frequency oscillator to the former version of
the servo gain adjuster.