Teac A-3300SX - Overall Performance Checks

20
8-19 SIGNAL-TO-NOISE RATIO —OVERALL—
Using blank Test Tape ........... YTT-8003
—
. Output and Line controls should be at the specified posi-
tions.
2.
Remove
the
AF
oscillator
from
the
LINE
IN
L,
R
jacks.
3. Place the deck in the Record mode with “no signal’
applied. Note the point on the index counter where re-
cording begins.
4, Rewind the tape to the beginning point and play it back.
5. The noise level as indicated on the VITVM should be
readings listed below.
TS5cips(2T) 9.22 a siti eine. bee 48 dB
7-1/2 ips(2T) ........... 48 dB
7-1/2 ips (4T) ........... 48 dB
3-3/4 ips(4T) ........... 46 dB
8-20 OPTIMUM ERASURE MEASUREMENT
Tape SPEED SW.......... HIGH
1. Thread the TEAC YTT-8003 Test Tape on the unit.
2. Apply a 1 kHz signal at 10 dB above the operating level
of --8 dB (308 mV) to the LINE IN jack.
3. Make a 30 seconds recording of the above signal while
reading and noting the level of output, then rewind to
beginning of this recording.
4. Disconnect the 1 kHz signal source (AF oscillator) from
the LINE IN jack.
5. Connect a VIVM to the OUTPUT jack, through a 1 kHz
Narrow Band Pass Filter.
6. Put deck in the Record mode and “record” (erase) over
this previous recording, then rewind to beginning again.
7. Put deck in Play mode and monitor the output on the
VTVM.
8. Difference in putput level, between the 1 kHz signal and
the “‘no signal” section level should be more than 65 dB
for 2 track decks and 68 dB for 4 track decks.
OSCILLOSCOPE
OSCILLATOR
DECK
under TEST
LINE IN
n
ATTENUATOR
%
ce r eo imi
Fig. 8-12 Test Connections for Erase measurement
8-21 CHANNEL SEPARATION
1. Be sure tape is completely bulk erased prior to doing
these checks.
2. Apply a 1 kHz signal at —8 dB (308 mV) to L chan.
3. Place deck in Record mode.
4. While recording, measure the OUTPUT on R chan with
VTVM connected through a 1 kHz Band Pass Filter.
Level should be — 45 dB
OSCILLOSCOPE
°
AMP. SPKR
DECK
under TEST
OSCILLATOR
ATTENUTOR LINE IN
ra)
VTVM !
jourPuT IkHz FILTER
T3981
Fig.
8-13
Test
Connections
for
Channel
separation
check
8-22 TRACK-TO-TRACK CROSS TALK
REJECTION (4 TRACK MODELS)
Following is the measurement procedure at 7-1/2 ips using
the TEAC standard tape, Type YTT-8003:
1. Thread a blank tape or the YTT-8003 tape on the unit.
2. Apply a 125 Hz signal at —8 dB to the right channel
LINE IN jack.
3. Make a 30 second recording of the 125 Hz signal.
4. Interchange the left and right reels and rethread tape on
the unit.
5. Connect a VIVM to the right channel OUTPUT jack.
. Playback the recorded signal portion of tape and moni-
tor the level on the VTVM.
7, The reading should be —35 dB.
ON
8-23 DISTORTION CHECK
Tape SPEED 7-1/2 ips
BIAS and EQSW ............ 1
1. Thread the TEAC YTT-8003 Test Tape on the unit.
2. Apply a 1 kHz signal to LINE IN jacks.
3. Place the deck in the record mode for about 10 seconds.
Rewind and play this recorded section of the tape.
4. Read the indicated value on the distortion analyzer.
5. The distortion factor should be 1.5% or less.