NAD L-53 Schematic

L 53 PRELIMINARY
SERVICE MANUAL
MAY 2005

SUBWOOFER MUTING

Install diode on the main board (component side), solder to resistor R689 (figure 1) with a long wire
connected to resistor R903 on the standby power-supply board (foil side), see figure 2

NEW DIODE 1N4148 CATHODE FACING R689

WIRE FROM DIODE ANODE

Figure 1 CUP11734-1

CUP11734-1

To R903 on CUP11732-6

To CUP11734-1
R689

Figure 2 CUP11732-6

CUP11732-6

ST_M

1N4148

ELECTRICAL PARTS LIST

■ RESISTORS AND CAPACITORS
Notes : ㆍParts numbers are indicated for most mechanical parts.
Please use this part number for parts order.
ㆍIMPORTANT SAFETY NOTICE.
Components identified by ! mark have special characteristics important for safety.
When replacing any of these components, use only manufacture's specified parts.
ㆍThe unit of resistance is OHM (Ω)
k=1000 (Ω) , M=1000 (kΩ)
ㆍThe unit of capacitance is MICROFARAD (uF)
P=10-6 uF

■ Numbering System of Resistor
Example
CRD 25 F J 101
Type Wattage Shape Tolerance Value

Resistor Type Wattage Tolerance
K[C]RD : Carbon 20 : 1/5W F : ±1%
K[C]RG : Metal Oxide 25 : 1/4W J : ±5%

50 : 1/2W K : ±10%
1 : 1W
2 : 2W
3 : 3W

K[C]RJ : Carbon,Chip 10 : 1/10w

14 : 1/4w

■ Numbering System of Capacitor
Example
HCKR 1H 101 K B
Type voltage Value Tolerance Peculiarity

Capacitor Type Tolerance

HCEA Type Other
HCB : Ceramic 0J: 6.3V 1H : 50V DC C : ±0.25pF
CCC : Ceramic 1A: 10V 1 : 125V DC G : ±2%
CCK : Ceramic 1C:16V KC : 400V AC J : ±5%
HCQI : Polyester 1E: 25V K : ±10%
HCQP : Polypropylene 1V: 35V Z : +80% , -20%
HCQS : Polystyrol 1H: 50V
HCUS : Ceramic 1J: 63V
HCEA : ELECT

Voltage

LOAD NO. PART NO. DESCRIPTION SPECIFICATION

CUP11732Y PCB, FRONT

CUP11732-1 V.F.D PCB
BN81 CJP14GB190ZC PIN HEADER
BK83,BK84 CMD1A374 BRACKET , FLT
C801,C802 HCBS1H223ZFT CAP , CERAMIC 0.022UF 50V Z
C803 HCBS1H220JCT CAP , CERAMIC 22PF 50V J
C804 CCEA1CKS101T CAP , ELECT 100UF 16V KS
C805 HCBS1H473ZFT CAP , CERAMIC 0.047UF 50V Z
C806 CCEA1HKS2R2T CAP , ELECT 2.2UF 50V KS
C807,C808,C812 HCBS1H223ZFT CAP , CERAMIC 0.022UF 50V Z
C813 HCBS1H104ZFT CAP , CERAMIC 0.1UF 50V Z
FL81 HFL11BT230GNK V.F.D 11-BT-230GNK