NAD Monitor 6300 Series User manual

MANUAL
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21/10/2013
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ALIGNMENT METHOD
IMPORTANT
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The tape path (heads, tape guides, capstan, plnch roller) should be cleaned and degaussed before alignment.
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This tape recorder is designed to work well with a variety of tapes, however, maxlmum performance will be obtained with recommended
tapes or similar tape formulations.
Recommendedtapes ForNorthAmerica For Europe-DIN
Type 1
MaxellUDS-1 MaxellUD-I,BASFTP18 no, R723DG
Type lI MawellXL-I1 MaxellXL-11, TeacMlT-5561
TYPe MaxellMX MaxellMX. MaxellMX 422
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All adjustments done with Dolby NR OFF. MPX filter (on back panel) OFF and BlAS FINE ADJUST in center position.
DOLBY NR level 200 nWblm
= 245 mV RMS on testpointsTP001(L) and TP002(R)KP003(L) and TP004(R) (PLAYBACWRECORDING) on
Maln PCB; approximately 505 mV at line outputs.
1. TAPE SPEED
Connect one output to Wow and Flutter Meter or Frequency
Counter, Play speedtest tape TEAC MlT-111
= 3 kHz or TEAC
MlT-211 = 3.15 kHz and adjust SVR851, for correct readlng
on Wow and Flutter Meter or FrequencyCounter.(See Fig. A)
Tolerance:
k 1 %
2. AZIMUTH
Connect VWM's andlor Oscilloscope to outputs. Set tape
selector to normal and start playing Azimuth tape TEAC
MlT-113 or MTT-114. Rotate azlmuth screw for maximum
output andlor maximum and in phase on Osdlloscope. Reseal
adjustment screw with nail pollsh or similar (do not use
glue).(SeeFig. B)
3. PLAYBACK EQ
MISADJUSTMENT IS NOT NEEDED UNLESS THE 'HEAD
HAS BEEN REPLACED OR REPAIR HAS BEEN DONE IN
HEADAMP CIRCUIT.
Play levellazimuthtape TEAC MTT-256 and adjust SVU001(L)
and SVR002(R) for identicaloutput at 31516300 Hz (MT-255)
or 25016300 Hz (M7T-256).
Tolerance: 20.5 dB
4. PLAYBACK HIGH FREQUENCY EQ
THIS ADJUSTMENT SHOULD BE DONE ONLY WHEN HEAD
HAS BEEN REPLACED.
Play frequency response tape TEAC MlT-258 or MTT-256U
and check playback level at 14 kHz.
Before adjust, cut the center of jumper leads E001(L) and
E002(A). Adjust by dlsconnectlng R001(L) and R002(R) If 14
kHz Is too low and connecting E001(L) and E002(R)
If 14 kHz
Is too high. Leave same component values In both channels.
Tolerance:
-+I dB
5. PLAYBACK LEVEL
Connect VWM to testpoints. Play Dolby NR lev% tape TEAC
MTT-150 and adjust SVROO3(L) and SVROO4(R) for 245 mV
RMS at testpoint TP001(L) and TP002(R) on Main PCB.
Tolerance: k2.5 mV
RMS
Output shouldbe approximately505.mV RMS.
6. METER LEVEL
Play Dolby NU level tape MlT-150 and adjust SVRSOl(L) and
SVR502(R) so that 0 dB LED'SJustturn on.
.I"
h
7. BlAS TRAP
Inserta blank type
1 tape and start recording.Turn recordlevel
all the way down and set tape selector to type
lV position.
Connect VNM's andlor oscilloscope probe to testpoint
MP201-3(L) and adjust F301 for minimum. Connect probe to
MP201-1 and adjust F302 for minlmum.
Tolerance: Less than 300 mV RMS.
8. RECORD LEVEL
Set tape selector to .we
N tape. Qonnect audio oscillator to
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llne Inputs, tuh r&ord levela to maxlmum (clockwise). Adjust
audlo
oscillator frequencyto 400 Hz andoutputqthat VTVM's
read 30 - 40 mV. (Use a condnlent referen-point on the
VNM's). r I 81
L 2
Reset tape countei~o0 anb release pause to start recording.
Recordfor approximately
5 seconds, rewindto0gntapewunter
andplay back while observingthe VTVM's. ~heh~'$should
Indicatethe same level as when the tape
was recorde8~djust
SVRDO!5(L) and SVROO6(R)
If neceseary and repeat the record
1play procedure untilthe readings are the same.
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Tolerance: 20.5 dB from record level. Less than 0.5 dB
dlfferencs between channels.
9. BlAS ADJUST TYPE I TAPE (NORMAL)
Set audlo generator to 1.2 kHz wlthout changing output level.
Reset
tape counter to 0 and start recordlng. Afler 5 seconds
change audlo generator frequency to 12kHz (do not stop the
machlne or change levels) and wntlnue recordingfor another
5 seconds. Stop and rewind to 0 on tape counter. Play back
whlle obae~ingVNM's. There should be no level difference
between the 1.2 kHz and the 12 kHz tone when played back.
If 12kHz Is
different inlevelfor 1.2 kHz, adjust SVRSOl(L) and
SVR302(R) and repeat the record I play procedure until both
frequencies play back at same level.
Tolerance:
f 0.5 dB
WARNING: Greater tolerance will grossly affect the Dolby NR
tracking and especially the Dolby C tracklng.
Reoord level (step 8) should be checked and if necessary
adjusted.
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10. PEAKING CIRCUIT TYPE I TAPE (NORMAL)
Adjust audio generator to 18 kHz while maintainlng the same
output level. Record and play back the 18 kHz tone and adjust
SVR201(L) and SVR202(R) to the samo level as the 1.2 kHz
signal.
/ Tolerance: +I dB
.
WARNING: If the RIP head is worn, the tape may not have
adequate contact with the head, resulting in severe drop outs.
Awornheadwillmake this adjustmentverydifficult or impossible.
DO NOT try to adjust the worn RIP head. Leave SVR2Ol and
SVR202 in the factory preset condition, or ~fthey have already
been adjusted, readjust them to their approximate mldposition.
11. FREQUENCY RESPONSE TYPE ll TAPE (Cr02)
Insert a type 11 tape and set selector to type U posltion. Adjust
audio generator to 1.2 kHz and 12 kHz and repeat process
described in step
9 using SVR303(L) and SVR304(R) to adjust
both channel simultaneously. ARer 1.2 kHz and 12 kHz are
adjusted properly, set audio generator to 20 kHz and repeat
sameprocessasdescribedinstep10whileadjustingSVR203(L)
and SVR204(R) to obtain correct reading.
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FRONT PANEL from rear side Adjust the semi-variable
resistor
(SVR851) on the
ALIGNMENT COMPONENTS LAYOUT
Flg. A FOR ADJUSTING TAPE SPEED
CASSETTE
MECHA.
I #
capstan motor PCB
through this hole.
MECHA. 1
CONTROL
Flg. C MAIN PCB
IC 701
"
12. FREQUENCY RESPONSE TYPE IV TAPE (METAL)
Inserta type
IV tape and set selectorto type IV positlon.Repeat
procedure aa In step
9 while adjusting SVR305(L) and
SVR306(R) for correct 12 kHz level In both channele. Set audlo
generator to 20 kHz and repeat process as In step 10 while
adjustlng SVR205(L) and SVR206(R) for correct 20 kHz record
level.
PC 8. VR85l ['Q G
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13. DYNEQ
Engage record and pause mode. Adjust audlo generator to 14
kHz andoutput sothat tape recorderoutput is -5 dB from Dolby
NR level
(approximately 280 mV RMS). Set tape selector to
type
I posltlonandconnect VrVM probetotest polntMP201-3(L)
(nearest rear panel) and adjust SVR207 from fully counter-
clockwiseposltlonuntiltheoutputontheprobedecreases
1 dB.
Connect
VrVR probe to test point MP201-1(R) (nearest to front
panel) and adjust SVR208 from fully counter-clockwise position
untll the output probe decreases 1 dB.
14. CAR
INPUT MONITOR
is in position, frequency 1 kHz SIGNAL to
LINE INPUT.AdJustS.G,outputsothat voltage at TP003, TP004
are 22 mV. CAR Is INposltion. adjust SVR101 and SVRlO2 to
increase 6.0 dB at TPO03. TP004.
Tolerance: f 0.5 dB
Flg. B FOR ADJUSTlNQ AZIMUTH
R/F' HEAD FRONT VIEW
IRCA JACK
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SVRIOI
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lEST POINIS REG LEVEL
u u SVROO3
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TPOOS-.--.-GNO
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MPZOI--.---BIAS TRAP A@J
5: a a 5 E a RO~~W2SVRg PLAY EP
DYtIEO. ADJ PLAY LEVEL
IPIOI.IOZ --.FINEBIASEFFECT
HEASVREMENT1.P
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OOLBY NR PLAY TRIM MONlTOR FINE TAPE SELECTOR
SW VR SW BIAS SW
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www.freeservicemanuals.info
21/10/2013
Worldwide electronic heritage manuals

www.freeservicemanuals.info
21/10/2013
Worldwide electronic heritage manuals