Teac A-650 - Overall Response and Noise Measurements; Overall Frequency Response Testing; Overall Signal-to-Noise Ratio Measurement

6-4-5. FREQUENCY RESPONSE -OVERALL-
Switch Setting:
BIAS
EQ LIMITER DOLBY NR
1 1
OUT OUT
OUT
5.
6.
TEST TAPE:
1 DOLBY NR:
Fig. 6-16
(BIAS/EQ3) ------
Fig. 6-17
6-4-6. SIGNAL TO NOISE RATIO -OVERALL-
Switch Setting:
BIAS
EQ
LIMITER DOLBY NR
OUT OUT
1
OUT 1
6.
28
Preparations:
Connection: See Fig. 6-6 (B) on page 22.
Preparations:
Connection. See Fig. 6-11 on page 25.
3.
4.
Specifications:
CrO 2 & Fe-Cr tapes: 46 dB (minimum)
Hi-Fi tape. 44 dB (minimum)
Load a TEAC MTT-505B test tape.
Apply and record a test signal from 30 Hz to 14 kHz
at -42 dB (6.15 mV).
Rewind and play this recorded section.
Make sure the readings on tire VTVM are within the
response limits.
In case of any deviation in the high frequency range of
the response limits, clean the heads and if this cleaning
is ineffective adjust L750/850.
Load a TEAC MTT-5O5B test tape.
Place the deck in the record mode for a few seconds
with no signal applied.
Rewind and play this recorded (erased) section.
Read the indication on the VTVM.
The VTVM should indicate — 51 dB minimum (2.18
mV maximum).
This — 51 dB corresponds to the specified signal-to-
noise ratio of 46 dB (minimum): the difference be 
tween the residual noise of — 51 dB and the specified
output level -5 dB (435 mV).
MTT-501
IN ------
MTT-505B
MTT-504
OUT
(BIAS/EQ 1)
(BIAS/EQ 2)
3.
4.
5.
“ 2 ” position
MTT-504
L751/851
LINE:
MIC:
LINE:
MIC:
I ’
'RIOUlSCV IS Hl
Overall Frequency Response Limits (for BIAS/EQ 1,2)
-t-i TEST TAPE:
4- ; DOLBY NR:
~ ........ -
n
\ Ln
m Uffl _ i
■ : Ti 1 ;
IRIOUISCV IS Hi
Overall Frequency Response Limits (for BIAS/EQ 3)
Control Setting:
OUTPUT: Specified Setting (See 6-2-2)
Specified Setting (See 6-3-2)
Minimum Setting
Control Setting:
OUTPUT: Specified Setting (See 6-2-2)
Specified Setting (See 6-3-2)
Minimum Setting
CrO 2 TAPE
1.
2.
CrO 2 TAPE
1.
2.
Fe-Cr TAPE
Repeat the above procedure, with the following ex 
ceptions.
BIAS/EQ switches:
Test tape:
Adjustments:
! Hili- 7
M K>» t? SX
i«
Hi-Fi TAPE
7. Repeat the above procedure, with the following ex 
ceptions.
BIAS/EQ switches: “ 3 ” position
Test tape: MTT-501
Applied frequencies: 30 Hz ~ 12.5 kHz
Adjustments: L752/852