Sansui BA-3000 - Main Troubleshooting on each Section

4-2. Main Troubleshooting on Each Section
1. Troubles on Power Supply Section
Symptom
1-1. Voltage +B not supplied to F-2513, F-2515 or F-2507
1) Defective AC line of power section 1,
2.
3.
4,
2) +85V, Input voltage not supplied to F-2508 5.
6.
3) +35V not suppied to F-2513 and F-2515 7.
8.
9.
4) +65V not supplied to F-2507- 10.
Laat.
12
. Defective ZD02 on F-2508
2. Troubles on Power Amplifier Section
2-1. Power Amplifier inoperative (Protector lamp lighted)
1) AC Fuse opens
2) AC fuse not opened —
2-2. Inproper Bias —— |
8
3. Buffer Amplifier or Subsonic Filter Inoperative
Wh
Sy :OE Bef
1) Low and high filter inoperative 1.
| [_,
2) MONO (B.T.L.) circuit inoperative 3.
aa
4. Troubles on Power Meter Circuit 1.
2.
3.
4.
5.
5. Troubles on Speaker Protector Circuit
1) Relay, RLO1 not switched OFF 1.
2
3.
2) RLO1 & RLO2 not switched OFF at the moment 4,
when setting power switch to ON 5.
6.
7.
3)
When
power
transistors
overheat,
protector
8.
relay
RLO1
inoperative
4) Protector indicator lamp not ie a
10.
_
Cause
AC Fuse F701 open
Imperfect contact of AC switch, $702
RO1 or RO2 open on F-2511
Inoperative inrush absorber circuit
FO1 or FO2 open on F-2511
Defective DO3 or D04 on F-2511
Defective DO1 or D02 on F-2508
Defective TRO1, TRO2 or TROS~TR11 on
F-2508
Defective ZDO1 on F-2508
Defective DO1 or D02 on F-2508
Defective TRO3, TRO4 or TR11~TR16
. Power transistor shorted
. TRO1 opened on F-2509
TR10 or TR11 shorted on F-2507
TRO8 or TROY shorted on F-2507
D06 or DO7 shorted on F-2507
TRO2, TRO6 or TRO7Z shorted on F-2507
VRO2 or VRO3 out of adjustment or defective
on F-2507
. TRO1 shorted on F-2509
Imperfect contact of $01 on F-2513
Defective TRO7~TR10 on F-2513
Defective MODE switch $701 or relay RLO1
Defective TRO2, TRO4 or TRO6 on F-2513
VRO1 or VRO2 out of adjustment or F-2515
Defective 1C0O1 or F-2515
Defective D01~D04 or F-2515
Defective TRO1~TRO3 or F-2515
Defective power meter
Defective D0O9~D14 on F-2511
Defective TRO3 or TRO4 on F-2511
Defective reley, RLO1
Defective C08 on F-2511
Defective TRO1 or TRO2 on F-2511
Defective relay, RLO2
RLO1 inoperative due to defective D17 on
F-2511
Defective posistor PRO1 on F-2509
Defective TRO5 on F-2511
. Defective LED, LD701
*As each voltage of speaker protector circuit floats from chassis, it can not be measued to the earth point.
. *Refer to Schematic Diagram.