dbx 224X-DS Service Instructions

Page 1

TYPE II NOISE-REDUCTION SYSTEM Model 224X-DS Service Manual

Notes: IRF 1MD is measured with 19 kHz and 20 kHz mixed 1:1, output 1 V. SHFTE IMD is measured with 60 Hz and 7 kHz mixed 4:1, output 1

Page 2

SPECIFICATIONS 2
ADJUSTMENT PROCEDURE
PERFORMANCE TEST
ADJUSTMENT POINT
SCHEMATIC DIAGRAM
SCHEMATIC DIAGRAM
BLOCK DIAGRAM
WIRING BOARD LAYOUT (1) Component Side View 15
WIRING BOARD LAYOUT (2) Foil Side View 16
WIRING BOARD LAYOUT (3) Component and Foil Side View
WIRING LAYOUT
EXPLODED VIEW
REPLACEMENT PART LIST 20-27

SPECIFICATIONS

• ELECTRICAL
Frequency response(40 Hz to 20 kHz)	+/-0.5 dB
(35 Hz to 20 kHz)	+0.5/-1 dB
(30 Hz to 20 kHz)	+0.5/-2 dB
Total harmonic distortion
( 30 Hz to 100 Hz)	0.5 %
(100 Hz to 20 kHz)	0.1 %
Intermodulation distortion	0.2 % (IHF)
	0.2 % (SMPTE)
Dynamic range(below 1V)	105 dB
Equivalent input noise	-88 dBV
Maximum input	6.5 Vrms
Maximum output	6.5 Vrms
Effective noise reduction	40 dB or more(depending on deck)
Unity gain(set at 200 mV)	Adjustable from 20 mV to 2 V
CENEDAL
O GENERAL
Dimensions(W x H x D)	19"(17-1/8") x 1-31/32" x 8-3/4"
	483mm(435mm) x 50mm x 222mm
	(without rack mounting bracket)
weight	5.95 LDs.
-	2./ kg.
Power consumption	13 W

Notes: IHF IMD is measured with 19 kHz and 20 kHz mixed 1:1, output 1 V. SMPTE IMD is measured with 60 Hz and 7 kHz mixed 4:1, output 1 V.

Power requirement ..... 100-120 V/220-240 V. 50/60 Hz

Page 3

BEFORE ADJUSTMENT

Confirm that the voltage-selector switch is in the proper position.
Inspect the unit to be tested and verify that all interconnect cables are properly installed.
Allow a minimum of 10 minutes warm-up for the test equipments and the unit under test.

INSTRUMENTS REQUIRED

Audio signal generator
Oscilloscope
Digital voltmeter
Distortion meter and and a board dial of total and the second and the second
VTVM (Vacuum tube voltmeter)
Frequency counter
Toneburst generator

• POWER SUPPLY TEST

1. Verify the following power-supply conditions:

	Probe location	Test condition	Tolerance
1	+12V	+12.0 V	+/-0.6 V
2	-12V	-12.0 V	+/-0.6 V

• LED TEST

1. Depress the power switch and verify that the POWER LED lights.

Mechanically center the calibration potentiometers VR701L, VR701R, V VX704R to the center of their angular rotation.

Page 4

• RMS SYMMETRY ADJUSTMENT

1. Set the controls as follows:

(RECORD/PLAY)
RECORD	Off
PLAY	Off
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE
(DUBBING)
SOURCE/1 > 2	1 > 2

2. Connect the signal generator to both L and R inputs desinated "TAPE RECORDER 1, FROM TAPE RECORDER OUTPUT" and apply a 100 Hz, -10 dBV(316 mV rms).

3. Connect the oscilloscope to TP 4, and set it to 2 mV/div and 50 ms/div.

4. Observe the output on the scope.

5. Adjust a potentiometer VR702L for the output becomes symmetrical and clear.

6. Repeat this procedure for equal peaks on the wave shape at the following test points and potentiometers .

VCA SYMMETRY ADJUSTMENT

1. Set the controls as follows:

(RECORD/PLAY)
RECORD	Off
PLAY	Off
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE
(DUBBING)
SOURCE/1 > 2	1 > 2

2. Mechanically center the calibration potentiometers VR701L, VR701R, VR704L, VR704R to the center of their angular rotation.

Page 5

3. Connect the signal generator to both L and R inputs desinated "TAPE RECORDER 1, FROM TAPE RECORDER OUTPUT" and apply a 1kHz, -10 dBV(316 mV rms).

(TAPE LEVEL - RECORD adjustment)

4. Adjust VR707 "TAPE LEVEL RECORD" on the front panel to obtain a output of -10 dBV at L ch desinated "TAPE RECORDER 2 - TO TAPE RECORDER INPUT"
5. Adjust VR703 for R channel.
6. Connect the X-axis probe of the oscilloscope to the TEST JIG* (see page 6) triangle wave output terminal.

7. Connect the Y-axis of the oscilloscope to R ch output terminal desinated "PREAMP OR RECEIVER TO PREAMP TAPE INPUT".
8. Apply a staircase wave shape output to TP 9.
9. Monitor the lissajous wave shape and adjust VR701R such that the output wave shape should be less than 5 mV.

10. Repeat this procedure for L ch, at test point TP 8 and VR701L.

(TAPE LEVEL - PLAY adjustment)

11. Adjust VR709 "TAPE LEVEL PLAY" on the front panel to obtain a output of -10 dBV at L ch desinated "TAPE RECORDER 2 - TO TAPE RECORDER INPUT"
12. Adjust VR706 for R channel.
13. Repeat paragraphs 6, 7, 8, 9 for testpoint TP 11 (TP 10 for L ch.) and VR704R (VR704L for L ch.)

Page 6

• LED DISPLAY ADJUSTMENT of another is bas i date of rederedes langle edd toennoo it

1. Set the controls as follows:

				Compared the constraints of the	and the second second
(RECORD/PLAY	()
RECORD		Off	tD" on the fr	"TAPE LEVEL - RECOR
PLAY		Off	RECORDER 2 -	oh desinated "TAPE
				for R channel.	Adjust VR703
(MONITOR)		to the	oscilloscone	-axis probe of the
TAPE 1/TAPE	2	TAPE	1	output terminal.
SOURCE/TAPE		TAPE

(DUBBING)

SOURCE/1 > 2 1 > 2

Connect the signal generator to both L and R inputs desinated "TAPE RECORDER 1, FROM TAPE RECORDER OUTPUT" and apply a 1kHz, -10 dBV(316 mV rms).
3. Adjust VR 01 for 4.5 Vdc at its center lead.
4. Adjust VR 02 so that the all four rows of LEDs read 0 dB.
5. Vary the level of the input from -60 dBV to +20 dBV in 10 dB steps and verify that the "RECORD IN" and "PLAY OUT" displays go from all LEDs off to all LEDs on in 10 dB steps (2-LED steps) over this input range.

TEST JIG

Page 7

• TRACKING TEST

1. Set the controls as follows:

(RECORD/PLAY)
RECORD	Off S.C. Off
PLAY	Off Cill of
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE

(DUBBING) SOURCE/1 > 2 1 > 2

2. Connect the signal generator to both L and R inputs desinated "FROM PREAMP TAPE OUTPUT" and apply a 1kHz, -10 dBV(316 mV rms).
3. Adjust the "TAPE LEVEL RECORD" control on the front panel such that the output voltage at the L ch and R ch "TO PREAMP TAPE INPUT" is exactly -10 dBV. 4. Verify the following levels:

INPUT LEVEL (dBV)	OUTPUT LEVEL (dBV)
0	-1 to +1
-10	-10
-20	-21 to -19
-30	-31 to -29
-40	-41 to -39
- 50	-51 to -49
-60	-61 to -59

FREQUENCY RESPONSE TEST

1. Set the controls as follows:

(RECORD/I	PLAY)
RECORD		On
PLAY		On

(MONITOR) TAPE 1/TAPE 2 SOURCE/TAPE

(DUBBING) SOURCE/1 > 2 1 > 2

TAPE

TAPE 1 WOLLON BUT DESCRIPTION AND THE SAME AND

Page 8

2. With a 0 dBV(1.0V rms) sinewave to both "FROM PREAMP TAPE OUTPUT" input jacks and verify that the outputs at the "TO TAPE RECORDER 1 - TO TAPE RECORDER INPUT" jack is as shown for the following frequencies:

FREQUENCY (Hz)	OUTPUT LEVEL (dBV)
20	+3.2 to +5.2
100	-0.5 to +1.5
lk	0
10k	-4.0 to -2.0
20k	+2.5 to +4.5

3. With a 0 dBV sinewave to both "TAPE RECORDER 1 - FROM TAPE RECORDER OUTPUT" input jacks and verify that the outputs at the "TO PREAMP TAPE INPUT" jack is as shwon for the following frequencies:

FREQUENCY (Hz)	OUTPUT LEVEL (dBV)
20	-17.0 to -15.0
100	-1.5 to +0.5
lk	0
lOk	+5.5 to +7.5
20k	-7.5 to -5.5

• THD TEST

1. Set the controls as follows:

(RECORD/PLAY)
RECORD	Off
PLAY	Off
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE
(DUBBING)

SOURCE/1 > 2 1 > 2

2. Apply a -10 dBV(316 mV rms) sinewave to "FROM PREAMP TAPE OUTPUT" input jacks at the following frequencies.
3. At the "TO PREAMP TAPE INPUT" jacks, measure the total harmonic distortion and verify that it does not exceed the following limit.

FREQUENCY (Hz)	DISTORTION LIMIT
100 (2nd H.D)	below 0.1 %
lk	below 0.1 % .
10k (3rd H.D)	below 0.1 %

Page 9

MAXIMUM OUTPUT LEVEL TEST

1. Set the controls as follows:

(RECORD/PLAY) RECORD	Off
PLAY	Off
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE
(DUBBING)
SOURCE/1 > 2	1 > 2

2. Apply a 1 kHz sinewave to "FROM PREAMP TAPE OUTPUT" and measure the output voltage at "TO PREAMP TAPE INPUT".
Verify that the output voltage is greater than approximately +16 dBV(6.5 V rms) at 1% THD.

NOISE TEST

1. Set the controls as the above.
2. Terminate the "FROM PREAMP TAPE OUTPUT" and "FROM TAPE RECORDER OUTPUT" inputs with 1 K-ohm resistor in parallel with 1000 pF to ground.
3. Verify that the noise level is less than -88 dBV. (with DIN audio filter)

• TONEBURST TEST

1. Set the controls as follows:

(RECORD/PLAY) RECORD	On
r LAI	OII
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE / TAPE	TAPE
(DUBBING)
SOURCE/1 > 2	1 > 2

2. Connect the signal generator to the toneburst generator, and connect the toneburst generator output to L and R ch. "FROM PREAMP TAPE OUTPUT" input jacks of the reference unit encoded.
3. Connect the output of the reference unit encoded to both "FROM TAPE RECORDER OUTPUT" jacks of the unit under test.

Page 10

4. Apply a toneburst of 50 cycles of burst(approx. 50-ms) and 500 cycles off(approx. 500-ms) of at least 40 dB attenuation at 1 kHz.
5. Observe the output wave shape at the "TO PREAMP TAPE INPUT" jacks of the unit under test.
6. Verify that there is no more than 20 % overshoot on the first cycle and no overshoot for the remaining cycles, including the end of the wave shape.
7. Replace the cable connecting the output of the toneburst generator to L and R ch. "FROM PREAMP TAPE OUTPUT" input jacks of the unit under test.
8. Connect the "TAPE RECORDER 1 TO TAPE RECORDER INPUT" of the unit under test to "FROM RECORDER 1 - FROM TAPE RECORDER OUTPUT" of the reference unit decoded.

9. Verify that the wave shape at "TO PREAMP TAPE INPUT" output of the reference decoder has no more than 20 % overshoot on the first cycle and on the remaining cycles.

Page 11

• LED DISPLAY TEST

1. Set the controls as follows:

(RECORD/PLAY)
RECORD	Off
PLAY	Off
(MONITOR)
TAPE 1/TAPE 2	TAPE 1
SOURCE/TAPE	TAPE
(DUBBING)
SOURCE/1 > 2	1 > 2

2. Connect the signal generator to both L and R inputs desinated "FROM PREAMP TAPE OUTPUT" and apply a 1 kHz, -10 dBV(316 mV rms).
3. Verify that the two rows of "RECORD (ENCODE)" LEDs now read 0 dB even if the "RECORD" switch is depressed.
4. Replace the cable connecting the signal generator output to "TAPE RECORDER 1 -FROM TAPE RECORDER OUTPUT".
5. Verify that the two rows of "PLAY (DECODE)" LEDs read 0 dB even if the "PLAY" switch is depressed.
6. Vary the level of the input from -60 dBV to +20 dBV in 10 dB steps and verify that the "RECORD IN" and "PLAY OUT" displays go from all LEDs off to all LEDs on in 10 dB steps (2-LED steps) over this input range.

Page 12

ADJUSTMENT POINTS

Page 13

SCHEMATIC DIAGRAM

Page 14

SCHEMATIC DIAGRAM

BLOCK DIAGRAM

Page 15

WIRING BOARD LAYOUT (1)

Component Side View

APSAB069AH

Page 16

WIRING BOARD LAYOUT (2)

APSAB069AH

Page 17

WIRING BOARD LAYOUT (3)

Component Side View

APSLD235AH

APSVR065AH

Foil Side View

APSLD235AH

APSVR065AH

Page 18

Page 19

EXPLODED VIEW

Page 20

Table of Part Structure

---(12) Chassis Assy -----(12) Switch Bracket Assy
---(AP11) APSAB069AH

---List 3. (Printed Materials)

---List 4. (Packing Materials)

---List 5. (Accessories)

L--List 6. (Shipping Materials)

LIST 1. SET ASSY ELEMENTS

Numbers with ( ) listed in Ref.No. has exploded details.

Ref.No.	MFR's Part No.	Description	Remarks
(11)	AY224DS*01	Front Panel Assy	8 148
(12)	AY224DS*02	Chassis Assy	1110
(AP11)	APSAB069AH	P.W.Board Assy	- Cami
1A	MS625AA002	Switch Cover
10	ML543AA003	Rack Mount Adaptor
13,15	NBR1255258	Push Knob
14	VK321SB001	Joint
16	VQ611SB008	Joint Switch
17	VS547XB001	Power Transfomer Sheet
18	MU985SX001	Cover
19	VVL511GE30	Serial No. Plate
311,16	BTPB3005ZB	Bind T.T Screw M3 x 5	2
312	BTPS3006TZ	Flat T.T Screw M3 x 6	a
B13	BSPB3012NZ	Bind Head Screw M3 x 12
B14	BSPB4010NB	Bind Head Screw M4 x 10
B15	BWU40855SB	IT.Lock Washer M4 x 8.5 x 0.5

Page 21

11. Front Panel Assy

Numbers with ( ) listed in Ref.No. has exploded details.

Ref.No.	MFR's Part No.	Description and the second	Remarks
(111)	AM224XDS01	Escutcheon Assy	1231
(AP111)	APSVR065AH	P.W.Board Assy
(AP112)	APSLD235AH	P.W.Board Assy	181233
112	VN276SB036	Flat Rotary Knob	0
113	MU542SD001	Volume Bracket	1 22
114	VS741SB001	PCB Holder
			51
B111	BTPS3006TZ	Flat T.T Screw M3 x 6
LD111	QLBLN222RN	LED (red) LN222RP

12. Chassis Assy

Numbers with ( ) listed in Ref.No. has exploded details.

Ref.No.	MFR's Part No.	Description		Remarks
121	MU984SL001	Chassis	BRECLIGHTSZ	82
122	MB951SL008	Rear Panel		83
(123)	AY1BXDS*03	Switch Bracket Assy
124	NBR9227577	Foot Assy		01,2181/8,2191/8
				7221/8,7231/8
AC121	ACAC029ULA	AC Cord Assy		142L/R, 143L/
ACB121	VM270NB001	Bushing		1462/8, 1470/9
B121	BTPW3008AB	Bras Tap Screw M3 x 8		CO2.05.06.07.49
B122	BTPB3005TB	Bind T.T Screw M3 x 5		09,10,12,2030 8
B123,124,126,128	BTPB3005TZ	Bind T.T Screw M3 x 5		1 2641/3
B127	BTPL3006TB	Round Head Wood Screw M3 x 6		1004,801,802,800
B129	BWM30705SN	Flat L Washer M3 x 7 x 0.5		108
				111
PT121	TPL41A001K	Power Transformer	CCGB270JOT	613,14
				015
S2	SS010226AJ	Slide Switch		C701L/R, 709L/R
				11 1997 01 100 1/1

111. Escutcheon Assy

MFR's Part No.		Description		Remarks
ME95EAA051	Escutcheon			11.1985 (A\.386\)
VF132SB004	Button Guide	mili a		7121./R. 7131./K.
VF122SB004	Button Guide			7361/3.7371/8
	MFR's Part No. ME95EAA051 VF132SB004 VF122SB004	MFR'S Part No. ME95EAA051 Escutcheon VF132SB004 Button Guide VF122SB004 Button Guide	MFR's Part No. Description ME95EAA051 Escutcheon VF132SB004 Button Guide VF122SB004 Button Guide	MFR's Part No. Description ME95EAA051 Escutcheon VF132SB004 Button Guide VF122SB004 Button Guide

Page 22

123. Switch Bracket Assy

Ref.No.	MFR's Part No.	Description	Remarks
1231	ML544SD004	Switch Bracket
			(1.10 22) 1011 POL
B1231	BTPB3005TZ	Bind T.T Screw M3 x 5	AP1127 Y224
C1	CKDU102KBM	Ceramic 1000 pF 125V +/-10%	1
C2	WUA322EEXX	Hi-Wrap Wire	11
			11
S1	SP01AAW07A	Push Switch

AP11. P.W.Board Assy (APSAB069AH)

Ref.No.	MFR's Part No.	Description		Remarks
	PSAB069C0X	P.W.Board (without parts)
R1	BRU3280XA1	Thin Head Rivet M3 2 x 8 0		108.197
B2	BNHCI 30NS7	Heya Nut M3		101
B3	RSPP3008N7	Pan Head Screw M3 x 8		ber
	DOITIGUOUL			The second
CO1 7181 /R 7191 /R	CEVG010ALX	Electrolytic 1 uF 50V		171
7221 /R . 7231 /R	of the test
742L/R.743L/R	and the second second			10176
746L/R.747L/R				Istenizi
807	and and the second
C02.05.06.07.08	CO4B103JTH	Film 0.01 uF 50V +/-5%		rera
09,10,12,703L/R		Rind L.T. Screw M3 x 5		6122
704L/R	2012444000			18123.124.126.1
C04,801,802,803	CEAF471ALX	Electrolytic 470 uF 35V	872005 1978	BIZZ
804		Flat L Washer N3 x 7 x 6.5		8129
C11	CEVE4R7ALX	Electrolytic 4.7 uF 25V
C13,14	CCGB270J0T	Ceramic 27 pF 50V +/-5%		191121
C15	CQ4B124JTH	Film 0.12 uF 50V +/-5%
C701L/R,709L/R	CCGB101J0T	Ceramic 100 pF 50V +/-5%		52
725L/R,727L/R
733L/R	VM.5110530
C702L/R,726L/R	CCGB221KOT	Ceramic 220 pF 50V +/-10%	;
C705L/R,732L/R	CQPC103GEH	Film 0.01 uF 100V
C706L/R,707L/R	CQ4B154JTH	Film 0.15 uF 50V +/-5%
730L/R,731L/R	BSPESCIERZ			11th Esculoive
C708L/R	CQSC101GEF	Film 100 pF 100V
C710L/R,711L/R	CQ4B104JTH	Film 0.1 uF 50V +/-5%	MFR's Part No	.08.108
715L/R,734L/R				mere conservestill
735L/R,739L/R			NEB2EVV021	IIII
C712L/R,713L/R	CQSC332GEF	Film 3300 pF 100V	VF13258004	1112
736L/R,737L/R				EITI
C714L/R,738L/R	CQSC331GEF	Film 330 pF 100V

Page 23

Ref.No.	MFR's Part No.	Description of the state	Remarks
C716L/R,740L/R	CQ4B123JTH	Film 0.012 uF 50V +/-5%	0.36
C717L/R,741L/R	CKGB102KBT	Ceramic 1000 pF 50V +/-10%	839,7570,60
C720L/R,744L/R	CSVE100KLN	Tantalum 10 uF 25V +/-10%	840,41,42,43,44
C721L/R,724L/R	CEVE100ALX	Electrolytic 10 uF 25V	45,46,47
745L/R,748L/R	000516179688	RD25523183X Carbon 97128MW 188 ohm 33/	1851, 53, 55, 57, 39
805,806,808	00000001268		61,63,65,67,89,71
C729L/R	COSC201GEF	Film 200 pF 100V	1024
CN01	Y.1F04S0437	Junction Jack	100 00 81 57 N 250
CN02	Y.1F06S0357	Junction Jack	1 81 82 83 84 88 88
CNOS	Y 1E0BS0287	Junction Jack	7991 10 7601 17
Chub	1010030202		01 10050
01	00710551 #N	Diada (zanan) MA10561	al intera
D1	QUZIUSOL#N	Diode (zener) MAIOSOL	an in it in it in the the
	QUZIUSIM#N	Diode (zener) MAIOSIM	UTATT'S/TABAT
U501L/R,502L/R	QUZIIZOM#N	Diode (zener) MAIIZUM	1.1214/1/1/JCC1
503L/R,504L/R		The week state with a set weeks and the set of the set	N1111, N/161/0
D801,802	QDSN4003AZ	Diode IN4003	HATTA AN TERE
D803	QDSMA150XN	Diode MA150	7361/8,7421/1
D804	QDSW02MXXG	Diode W02M	745L/R,746L/R
	83		R706L/R,737L/
HS1	MS736AD001	Heat Sink	82.071/0.2331.41
			734L/R 738L/R
J701,702,703	YJP02S033Z	Pin Jack (2P)	P.2121./R.2431./I
704.705.706	- Westernes an	ROZEPJEGIX Carbon I/4W 100-mbd- #/	RALEIVE
1111	separate and an	ADDRESS MAN ANT A	DU LANC BU LATUR
PA	AC77460111 A	Farth Wire Assy	01 ICAT 01 IATED
DE	ACCNI 73III A	Connection Cond Assu	I mar of mered
F.5	ACCILIZOLA	connection cord Assy	Di lost di losta
01	0701204201		A abox, ALacator
19	QTC1384XGN	Transistor 2501384 (R,S)	TTTEL'N/JAZAN
Q701L/R	Q1K0364X11	Transistor 25K364 (BL,GR)	111267,0111248
Q801	QTA1015XTT	Transistor 2SA1015 (Y,GR)	11/221/19,3631.19
APTIN, P.W.Bpan	Assy (APSVRA		RY 1847, R , 754L/R
R01,02,03,06	RD25PJ332X	Carbon 1/4W 3.3K ohm +/-5%	R224L4R,755L/B
R04,05,07,08,09	RD25PJ103X	Carbon 1/4W 10K ohm +/-5%	N725676855667/0
10,11,12,18,26	1		R126L/R, 257L/II
27,28,33,708L/R	5%X03230AV24	RD25P3100X Carbon(stree states 10 ohes. 4/	R727L/R, 763L/I
739L/R,801,802	58		R728L/R, 244L/R
R13,14,73	RD25PJ822X	Carbon 1/4W 8.2K ohm +/-5%	7590/8
R15.22	RD25PJ224X	Carbon 1/4W 220K ohm +/-5%	R730L/R
R16.20.7091 /R	RD25PJ392X	Carbon 1/4W 3.9K ohm +/-5%	8731178
7401 /8	NOLOT COULT	the state of the s	at trat of mater
P17 10 25 32 35	PD25P 1102X	Carbon 1/AW 1K ohm +/-5%	at inata-
37 38 48 7011 /0	NUL JI UIVEN
7301 /p 7601 /p
/J2L/K,/00L/K	0000010004	Caphon 1/44 200K abm 1/5%
KZI	RU25PJ204X
R23	RD25PJ244X	Larbon 1/4W 240K ohm +/-5%	016
R24	RD25PJ912X	Carbon 1/4W 9.1K ohm +/-5%	RITAL/R. NZLIM
R30	RD25PJ122X	Carbon 1/4W 1.2K ohm +/-5%	RD3
R31,49,50,52,54	RD25PJ363X	Carbon 1/4W 36K ohm +/-5%
56,58,60,62,64		SPOLAAXBLA Bush Switch	501.02
66,68,70,72			503
R34	RD25PJ823X	Carbon 1/4W 82K ohm +/-5%
New York Street Street			2/4

Page 24

Ref.No.	MFR's Part No.	Description		Desc	ripti	ion of the 2'Alk	Remarks
R36	RX2ATJ100B	Metal-oxide	2₩	10	ohm	+/-5%	CIEL P. 740LO
R39,767L/R,804	RD25PJ105X	Carbon	1/4W	1M	ohm	+/-5%	CTLALAS, MILLA
R40,41,42,43,44	RD25PJ821X	Carbon	1/4W	820	ohm	+/-5%	C720L/8,744L/9
45,46,47		of , 25V					6721L/R,724L/H
R51,53,55,57,59	RD25PJ183X	Carbon	1/4W	18K	ohm	+/-5%	7451/8,7481./9
61,63,65,67,69,71		Conservative.					805,808,208
R74	RD25PJ753X	Carbon	1/4W	75K	ohm	+/-5%	C729L/R
R75,76,77,78,79,80	RD25PJ472X	Carbon	1/4W	4.7K	ohm	+/-5%	TOND
81,82,83,84,85,86	eners Laboration 1						CN02
729L/R,760L/R	Designation of the						EQUO
R702L/R	RQBPF3573X	Metal-oxide	1/4W	357K	ohm	+/-1%
R703L/R	RQBPF1214X	Metal-oxide	1/4W	1.21M	ohm	+/-1%	10
R704L/R,710L/R	RQBPF1002X	Metal-oxide	1/4W	10K	ohm	+/-1%	02
735L/R,741L/R							0501L/R, 502L/R
R705L/R,711L/R	RQBPF3322X	Metal-oxide	1/4W	33.2K	ohm	+/-1%	503678.594678
714L/R,717L/R	el fue o ucoosa						0801,802
736L/R,742L/R	and the second se						£080
745L/R,748L/R	TR'S PETT SO.						0800
R706L/R,737L/R	RD25PJ470X	Carbon	1/4W	47	ohm	+/-5%
R707L/R,733L/R	RD25PJ104X	Carbon	1/4₩	100K	ohm	+/-5%	121
734L/R,738L/R
R712L/R,743L/R	RD25PJ221X	Carbon	1/4W	220	ohm	+/-5%	3701.202.203
713L/R	RD25PJ101X	Carbon	1/4W	100	ohm	+/-5%	204 205 206
R715L/R,746L/R	ROBPF9092X	Metal-oxide	1/4W	90.9K	ohm	+/-1%
R716L/R.747L/R	ROBPF4751X	Metal-oxide	1/4W	4.75K	ohm	+/-1%
R718L/R.749L/R	ROBPF6811X	Metal-oxide	1/4W	6.81K	ohm	+/-1%
R719L/R,750L/R	RD25PJ203X	Carbon	1/4W	20K	ohm	+/-5%
R720L/R,751L/R	RD25PJ223X	Carbon	1/4W	22K	ohm	+/-5%
R721L/R.752L/R	ROBPF 3012X	Metal-oxide	1/4W	30.1K	ohm	+/-1%	statest
R722L/R.753L/R	ROBPF3011X	Metal-oxide	1/4W	3.01K	ohm	+/-1%	TARO
R723L/R.754L/R	RGOCPJ226X	Metal-oxide	1/4W	22M	ohm	+/-5%
7241 /R. 7551 /R	RD25PJ274X	Carbon	1/4W	270K	ohm	+/-5%	30 50 50 109
87251 /R . 7561 /R	RD25P.J200X	Carbon	1/4W	20	ohm	+/-5%	PD 80 55 30 100
7261 /R 7571 /R	ROBCE1654X	Metal-oxide	1/4W	1.65M	ohm	+/-1%	ST TE DE
7271 /R 7631 /R	RD25P.1100X	Carbon	1/4W	10	ohm	+/-5%	aliant es an co
7281 /R 7441 /R	RD25P.1471X	Carbon	1/4W	470	ohm	+/-5%	Chie mis as ibre
7591 /R	NOLOI O ITTA	ourbon	1/ 1/	110	onn		55 65 510
7301 /R	ROBPEIDOIX	Metal-oxide	1/4W	1K	ohm	+/_1%	20,21,010
7311 /R	ROBPELOOSX	Metal-oxide	1/4W	1006	ohm	+/-1%	a upar as are
7581 /R 7611 /R	ROBPF4991X	Metal-oxide	1/4W	A GOK	ohm	+/-1%	IN HOAT
7621 /P	ROBPEA003X	Metal-oxide	1/4H	4.99K	ohm	+/-1%	11
764	RQDF1 4995X	Carbon	1/44	4331	ohm	+/-5%	DULING PA 96 TS
765	RD25P 1225Y	Carbon	1/41	2 2M	ohm	+/-5%	AU1101,09,00,10
766	RD250 11 64V	Carbon	1/41	1504	ohm	+/-5%	132618,10011
770	RD25P0154A	Carbon	1/41	2 74	ohm	1/ 5%	1.53
7711 /0 7721 /0	DORCE1924	Motal outda	1/4₩	1 004	ohm	+/ -5%	823
1/1L/K,//2L/K	RUBUE 1824X	Gambon	1/4₩	1.82M	onm	+/-1%	ASA ASA
(005	KUZSPJ303X	carbon	1/4₩	SOK	onm	%C-\+	130
01 02	SDOIAAVDIA	Duch Suddah					121,48,38,38,24
501,02	SPUTAAXBIA	Push Switch					10, 10, 00, 82, 82
503	SPUSTAXIIA	Push Switch					55, 58, 70, 72
and the second second	PROTECTION OF PE				0000		RSA

Page 25

Ref.No.	MFR's Part No.	sit() tis	Description	Assy (APSL020	Remarks
U01,02,03	QQM04558A&	IC Determined	4558	df81s Part No.	. ok instruction
U04	QQM02903AJ	IC	JRC2903
U05	QQ004051DE	IC	M4051BP
U06	QQM54563AE	IC	M54563P
U07	QQM54517PE	IC	M54517P		(18 01))
U08	QQ000412CB	IC	HMCS412C		- (2V (13)
U701L/R,702L/R	QQM0353NYL	IC	LF353N
U703L/R,707L/R	QQM01252AA	IC	uPC1252H2
U704L/R,708L/R	QQM01253AA	IC	uPC1253H2
U705L/R,706L/R	QQM00353NL	IC	LF353N
U801	QQM07812CJ	IC	NJM7812A
U802	QQM07912BJ	IC	NJM7912A
VR01	RP1NB203#1	Potentiometer	20K ohm-B
VR02	RP1NB103#1	Potentiometer	10K ohm-B		Assy national transfer
VR701L/R,702L/R 703,704L/R	ERP63H50301*02	Potentiometer	50K ohm-B		New Part Code
705L/R,706	ACCOUNCE
XT01	ECX15000201*01	Ceramic (OSC)	1.50 MHz		New Part Code
ZZ01	VS223RH002	Silicon Sheet
ZZ02	VF164DN003	Bushing
ZZ03	NBR2666116	Collar Bushing	q
ZZ04	NBR2675136	Collar Bushing	g

AP111. P.W.Board Assy (APSVR065AH)

Ref.No.	MFR's Part No.	Description	Remarks
	PSVR065C0X	P.W.Board (without parts)
P1	ACCNAC3ULA	Connector Cord Assy
VR707,709	RVNA503B17	Rotary Volume 50K ohm-B	1/1

Page 26

AP112. P.W.Board Assy (APSLD235AH)

Numbers with ( ) listed in Ref.No. has exploded details.

Ref.No.	MFR's Part No.	Descrip	otion		Remarks
	PSLD235C0X	P.W.Board (without parts)		400220220000	100
(LED A1)	AXLD008GEA	LED Assy	91 he 31/	00M54863AE 00M545517FE40
P2	ACCNAC4ULA	Connection Cord Assy	21 hai 21/		008 82011/8,2021/9
93	ACCNAC5ULA	Connection Cord Assy		OQHOIZEBAA	1704L/R, 708L/R

LED A1. LED Assy

Ref.No.	MFR's Part No.	Description	Remarks
n die Parte T	QLBLN222RN QLBLN322GN QLBLN422YN VB721SW002	LED (red) LN222RP LED (green) LN322GP LED (orange) LN422YP LED Case	7494_74 , 74%

LED A2. LED Assy

Ref.No. MFR's Part No.		Description
QLBLN222RN	LED (red)	LN222RP	AND ASSY (APSYNO	A.W.S. TITS
QLBLN322GN	LED (green)	LN322GP	MED'S DAVE NO	ALL TAR
QLBLN422YN	LED (orange)	LN422YP
VB721SW002	LED Case	and the set the state of the	k ronzanduza
	QLBLN222RN QLBLN322GN QLBLN422YN VB721SW002	QLBLN222RN LED (red) QLBLN322GN LED (green) QLBLN422YN LED (orange) VB721SW002 LED Case	QLBLN222RNLED (red)LN222RPQLBLN322GNLED (green)LN322GPQLBLN422YNLED (orange)LN422YPVB721SW002LED Case	QLBLN222RNLED (red)LN222RPQLBLN322GNLED (green)LN322GPQLBLN422YNLED (orange)LN422YPVB721SW002LED Case

LIST 3. PRINTED MATERIALS

Ref.No.	MFR's Part No.	Description	Remarks
1	KT224DSPXX	Owner's Manual
2	KW000341AX	Warranty Card
5	KF243400E4	Polyethylene Bag
			1/

Page 27

LIST 4. PACKING MATERIALS

Ref.No.	MFR's Part No.	Description	Remarks
41	KP224DS*01	Inner Carton
42	KS224DS*01	Outer Carton
43	KN1BX3**03	Partitioner L
44	KN1BX3**04	Partitioner R
45	KF604200E2	Polyethylene Bag No2
49	KN1BXDS*01	Pad A
			1

LIST 5. ACCESSORIES

Ref.No.	MFR's Part No.	Description	Remarks
51	ACSP023GEA	Stereo Audio Cable
			1/1

LIST 6. SHIPPING MATERIALS

Ref.No.	MFR's Part No.	Description	Remarks
61	KM224DSP01	Master Carton

Page 28


osificantes	MA's Part Ho.	aliaters \|

WFR'S Part No.

	Stereo Audibies



	-50-(nad)

dbx, Incorporated 71 Chapel Street, Newton Massachusetts 02195 617/964-3210

KD224DSPXX 0686TK Printed in Japan

dbx is a trademark of dbx Incorporated

dbx 224X-DS Service Instructions

CONTENTS

SPECIFICATIONS

BEFORE ADJUSTMENT

INSTRUMENTS REQUIRED

• POWER SUPPLY TEST

• LED TEST

• RMS SYMMETRY ADJUSTMENT

VCA SYMMETRY ADJUSTMENT

• LED DISPLAY ADJUSTMENT of another is bas i date of rederedes langle edd toennoo it

• TRACKING TEST

FREQUENCY RESPONSE TEST

• THD TEST

MAXIMUM OUTPUT LEVEL TEST

NOISE TEST

• TONEBURST TEST

• LED DISPLAY TEST

ADJUSTMENT POINTS

WIRING BOARD LAYOUT (1)

WIRING BOARD LAYOUT (2)

WIRING BOARD LAYOUT (3)

EXPLODED VIEW

Table of Part Structure

LIST 1. SET ASSY ELEMENTS

Numbers with ( ) listed in Ref.No. has exploded details.

11. Front Panel Assy

Numbers with ( ) listed in Ref.No. has exploded details.

111. Escutcheon Assy

123. Switch Bracket Assy

AP11. P.W.Board Assy (APSAB069AH)

AP111. P.W.Board Assy (APSVR065AH)

AP112. P.W.Board Assy (APSLD235AH)

Numbers with ( ) listed in Ref.No. has exploded details.

LED A1. LED Assy

LED A2. LED Assy

LIST 3. PRINTED MATERIALS

LIST 4. PACKING MATERIALS

LIST 5. ACCESSORIES

LIST 6. SHIPPING MATERIALS