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CIRCUIT ADJUSTMENT (Efififiifi)

Notes BEL Internal input resistance of volt-ohm meter should be higher than 10k Ohms
ix 7. Annmlomum 5 Ed-Milt??? ls

ESézi Adjustments should be made in case of the PC Board or Transistors being changed.
ElgleCrK- Fbéhlt i 51 '71? éilfiL/fl%éfioTT§lu

, In the DC Balance adjustment, though a normal volt-ohm meter can only indicate the oflset balance with a very small
amount of meter scale. adjust it carefully so as the meter to indicate exact ZERO polenllfllt
DC»? / X(OFFSFT) $113311 t f X 9 - Tfii'fialamlltaiéfi't Lion? SHH» 2 f. at? L T 7 x 7-mi3iffifii
intrxhlililliflflifTéh.
i=4. Adjustment is made at test point with shorting connector jack remOVEIL Aiter adiustmen! completed make sure to plug
test point with shorting connector jack.
5&127'1 It #34 / H7)? 5 - [- 35i~7 7/ i: 7 2411 LfiafTéls 1 fifiiéélidl~ifil)OHTTi-'ls
2365. After feeding 1-10 watts output for about 15 minutes, check bias adjustments again,
$711~10727 iifiiicififiihffiéttii. '4 Tzfifiéififz 7 7+5.

0 E
STEP ADJUST ITEM PRTLEIQLLARE ADJUST REMARKS
- -- TEST E PT I COVECTIVG POINT t} ' ' IX 2 z!
17' (7 Wfilfifi as? i - if": H .fiilfr flu. iii 1
HEAD AMP, EQUALIZER AMP ASSEMBLY (711-0014-00)
«"1 F777. 4 =54'thss'y
lnput OFFSET of Lch. Disc lnput Jack of Let
1 Head Amp. with Head Amp al 0N VRl
\-'/ l'rvatthnn 1h Leh. plsc new", Amp 0N]
lnput OFFSET of Rchi Disc input Jack of Rcll. See :22 3
2 Head Amp. with Heal Amp ll 0N m
\'7 r7 77Rch1/K7JT7-cv h lleh DlSC AMT-m. Amp om
Out I OFFSET { L h, V-°~ 9'" S" "E . . .2 . _ , s
3 Pu Okla-id Amp. m less than DCO.3V Termlnnl L. and Chassis \'R3 Adjust [or 0
\';' F7>7thwn2r7epi T $4 7 - EVT-9lfi reading of v,oi Meter
°"' OFFSET °HR°:A _ Terminal "R and Chassis VR
4 , _ , N P- 719- ixtgixi 'lt' t~/T-~/l'a1 T17-m3fii"0t:ifil§
«27h7/7Rehnlmz7e-2l Dcowum-mvyy |
output OFFSET of Lcll.
REC our Jack oi Lcll.
s Equalizer Ampi VR5
4:?4V777Lchniiht7t-Il LC C OUT 1?
0W OFFSET ° 3" REC OUT Jack of Rch.
e Equalizer Amn R h REC our _ vns
tfiternvkehmlinrvt-yl a"
TONE AMP ASSEMBLY (7|2-oot4-00)
I-/7/7'Ass'y See 32:3
1 Output OFFSET Tiffani, v.02 Meter Set range PRE OUT Jack of Lchi vm M 1 f 0..
n i w . jus or
i-yTV7LcllJI277ff7t-yl" ° 5 m" DCMV LC PRE OUT 1' reading of v.0. Meter
output OFFSET or Rcll. _ _
2 Tone Amp. Dco 3:;1Zflv 2. :RhE :13; 33°15 gig \le ~71 7-miEa-<0"l:$l§
l-yTVYRchiHfiXTt-yi ' " "'
POWER AMP ASSEMBLY (717-0017-00) See 222 4
I\"7--7/7Assy - 222' 5
1 Bins Current at L152; r Amp v.0. Mn" 5 range Tt;tRPainl Psi: +l ajlltlkl-l VR1 M n v
\e . . . . . s .
w I > h DCO.3\ ( emote orlulg ac .) f L h just or m
Len/"4 Txlt'tin ° 9 ' " lhen mitt sure lo Plug " reading at v.0. Meter
Bias cum, 0, ML _ ill-21H 2 he. 6 ray-msTT-cumv'
2 Power Amp 77" _ (meta: ~> s- h 75 7'2) VR Ema:
Rsh.»<47inn DCO,3VLAF7)V// (31 Latgwmiimsz 0' ML
METER CALIBRATION (Located Speaker 5w Assembly 7|6-0l26 or 7|6-0l40-00)
x-ymg
Note Adjustment should be repeated until correct meter indication is obtained
1 ~4mmxélil-5msfi'infiu < assT-ztlilreéLtFéll.
Peak-0 dB Calibration Adjust inpul signal so thit vrvn
I for LcIl. VR3 reads 34.6IV. Then adjust VRJ and
:0 dB .~ VIN so that Meter read 0 dB.
LcIl hi VTVM VT\'Mmlh'13L64Vl"xZ>J\7Jl3€'
Peak-l) dB Calibration 2AA. 1-77h'i7fifl0 dBM-ts
2 lor Reh, vm :ilfl'RSA'zflfl
Rch :0 dB SEE input: lltHz Sine Wave ; Speaker Terminals i
~30dE Calibralion M: lItHziEt-zi'a j lama?- Atliust input signal so that vrviil
3 (or Lch | VRj read LIN-MB). Then adjust
Lch Z -30dB GEE VRI and \'R2 so that Meter reads
Load I None -30dB.
-30dB Calibration ! vTvumsrl . lv -30dB) e as A
4 j for Ken; VR2 mm: angry-sow
Rclt : -30dB cm i no: warming

CIRCUIT ADJUSTMENT (@fifilflg)

Test Point for Bias Current
Rah. Power Amp Assembly
717*001700)
I

Lch.
Power Amp Assembly Test Point for
2717 001700) le artmtadogifm
TOP
I l
VRl (Bias) I'm VRI (Len)
vamchl H d A
3:qu VR21RchJ '3 'P
'QIi VR4(Rch.)
Test Point

Hi]

[or Bins Current

VRG
Equalizer Amp

VR5

Head Amp l
Equalizer Amp 1 Assembly

VR4 (Rch20dB) (711-0014 00?

ILch: - 3MB}!

Speaker Switch Assembly VRSiLt-h10d3)
i716 0126 001

VR2 1R h:-- d 1
I716 0140-00) C 30 B

BOTTOM

mw-nm-uumi-«nw

ans-unint- ".

Tone Amp Assembly
(712»0014-00)

Power Amp Assembly CHECKING/ADJUSTMENT of Power Amp Stage
I\"7-7"/7'I!§0>-7-1~7 7

SHORT terminal
{or class-C
Under normal circumstances, heat sink is indispensable
for final stage However, if it is operated under class-C

TESI Pom for EMS temporarily, circuit check can be made without heat sink,

x 4 xlilifiliiérirmimfifli t- r >7 flfidZ-E'CTfit
CiMMFE éfl-Z-rfiilC; c'C t- l- >7 72:;LC'ééiliém
57; I 73-5433??? 3T,

' After adjustment make sure to plug to the test-point
with shorting connector jacki

muffins/177927 7031f1éfifllflbs

Remove the shorting jack, and plug it
to the SHORT terminal
=2»: 7211?! s SHORT mfl-T-«Anb.