Teac V-2RX - Electrical Checks and Adjustments; Electrical Adjustment Precautions; Playback Performance Checks

_V-2RX/V-GRX |
5
ELECTRICAL
CHECKS
AND
ADJUSTMENTS
PRECAUTIONS :
1. Before performing adjustments and checks, clean and demag-
netize the entire tape path.
2. Make sure the deck is properly set for the voltage in your local-
ity.
3. In general, adjustments and checks are made in the order of
L-ch then R-ch. Double REF. Nos. and test point designations
indicate L-ch/R-ch. (Example: R11/R21)
Oscillator Distortion Analyzer
Attenuator
. 0 dB is referenced to 0.775 V. If an AC voltmeter thi references
0 dB to 1 V is used, appropriate compensation should be made.
. The AC voltmeter used in the procedures must hav@ an input
impedance of 1Mo or more.
. Note the “deck settings” at the top of each chart. The settings
apply to all checks for a specific chart unless explicitly stated
otherwise.
Oscilloscope
AC Voltmeter
1kHz Filter
LINE IN OUTPUT
Fig. 5-1 Basic test setup
Deck settings:
LEVEL cont.: OFF (depressed) .
MONITOR sw TEAC test tapes:
{V-2RX only): TAPE MTT-150: For Dolby level calibration
NR SYSTEM sw: OUT MTT-356: ‘For playback Lh barten 4 response
TAPE sw: METAL check for METAL, Co (CrO2)
5-1 PLAYBACK PERFORMANCE OUTPUT cont.: MAX MTT-501: For S/N check with NORMAL
ADJUST MEASURING
ITEM SETTING INPUT SIGNAL (or CHECK) POINT: RESULT REMARKS
: OUTPUT: Refer to Fig.
. REC-PLAY MEDIC eneee Phase: within 45° 5-5.
head Connection: Fig. 5-2 Azimuth screw | OUTPUT:
azimuth
MTT-356 (12.5 kHz)
of R-P head
(Figs. 5-3, 5-4)
Max. output at L-&
R-ch’s (on VTVM)
. Specified
output
——
level
MTT-150
OUTPUT: Spec. output
R11/R21
~3.5
dB
(518
mV)
level
. PEAK PRO-
PEAK PROGRAM
GRAM LEVEL — MTT-150 R15/R25 LEVEL METER:
METER 0dB
TAPE sw: METAL
If 10 kHz output is lower
then spec, connect C107 MTT-356 Check OUTPUT: Fig. 5-6
(C202) in parallel with C101
(C201) on REC/PLAY AMPL
. Frequency PCB.
response
TAPE sw: NORMAL MTT-356
OUTPUT: At 10 kHz
should be approx.
Check 4 dB higher than
measured in above
step.
F
i
Fully-erased
Ratio
of
spec.
.
Signal-to-noise
:
.
OUTPUT:
ratio
TAPE
sw:
NORMAL
MTT-501
tape:
Check
47
dB
min.
outp
ut
of
(Use bulk tape eraser)
-3.5 dB to noise