Teac V-2RX - DBX PCB Adjustment; DBX PCB Adjustment Preparation; DBX Encoding Adjustment Procedures

~ V-2RX/V-4RX
14
5-6 DBX PCB ADJUSTMENT
Note:
Since the DBX PCB assembly has been precisely adjusted at the
accidental damage when disconnecting or reconnectilg.
factory, this section adjustment is not usually needed unless any of 2. Make the following initial settings.
the trimmers have been changed, or any components on the PCB
have sustained damage.
5-6-1 PREPARATION
1. Disconnect the wires from the P501 and P503 connectors (P503
for V-2RX) on the DBX PCB. Turn the deck OFF to prevent
e POWER switch: ON (for supplying power vi the P502
connector to the DBX PCB).
NR SYSTEM switch: OUT
DBX PCB trimmers: Approximate center positiins
All other front panel switches and controls have no effect
on this adjustment.
5-6-2 ENCODING ADJUSTMENT
ITEM SETTING
100 Hz/-8.2 dB
INPUT SIGNAL
For V-4RX, check in the REC/PAUSE mode.
ia one RESULT REMARKS.
Clean 200 Hz sine- Refer to Figs.
wave. 5-12and 5-13.
Check
R52/R62
*1 ,
Reference
1
-8.2
dB*?
(300
mV)
*2
Reference
2
(300 mv)
1.
RMS
SYM
soo
nv
me
*1
2.
Encoding
level
pela
Nad
dB
3.
VCA
SYM
400
Hz/-8.2
dB
Min. distortion
(0.16% or less)
R51/R61
100 Hz/—8.2 dB
(300 mv)
4. Encoding single
frequency re-
sponse
(300u V)
5. Encoding opera-
tion level
(3.00 V)
Low distortion
AF OSCILLATOR
Distortion: 0.02% or less
Output: 3 V or more
Fig. 5-12 RMS SYM check (incorrect)
Low distortion
AF OSCILLATOR
Distortion: 0.02% or less
Output: 3 V or more |
; —3.3 dB+0.5 dB against
10 kHz/-8.2 dB Check Ref. 2
(194 mV ~ 217 mV)
400 Hz/~68.2 dB*? -30 dB+0.5 dB against | «3 -60 dB
400 H2/+11.8 dB**
+0.2 dB+0.5 dB against
Ref. 2
(290 mV ~ 325 mV)
Ref. 2
(8.96 mV ~ 10.1 mV)
+10 dB+0.5 dB against
Ref. 2
(0.896 V ~ 1.01 V)
Distortion: 0.3% or
less
against Ref.1
*4 +20 dB
against Ref.1
OSCILLOSCOPE
DBX PCB AC VOLTMETER
P502 7
+ CONNECTED
ATTENUATOR TP 53 ©@®
: ©6©® are mess ©@®
DBX PCB _INPUT|
P502 —
attenuator | CONNECTED
es
{TPE
o © OTP.SHTPEI} METER
[@@@ yn
@©@®
©@®@
EXT.
TRIG.
Fig. 5-13 RMS SYM check (Correct)
Fig. 5-15