Classe Audio CAV-180 Wartungshandbuch PDF herunterladen (Seite 8)

PRO-SVR_LEGACY Page 8 of 13

Output Transistors Testing and Replacement

PLEASE NOTE THAT THESE TESTS ARE ONLY EFFECTIVE ON BIPOLAR TRANSISTORS.

DO NOT PERFORM THESE TESTS ON MOSFET DEVICES, AS THEY ARE LIKELY TO

BECOME SHORT DURING THE TEST.

You should check all pin combinaisons, as there is a chance that only one side of the transistor is short. When

replacing outputs transistors, the technician should first disconnect both outputs and main board to check if

the blown outputs were caused by a faulty component on the amplifier’s base. Blown output transistors should

be replaced by kits, not individually. These kits contains matched transistors for both rails of one channel.

When replacing blown output transistors, you must also replace positive and negative Mosfet drivers and bias

transistor. Carefully inspect 4.7ƻ resistor and 10ƻ soft start resistor, and replace if necessary. Replace any

burnt component or board.

Pins : 1 Base

2 Collector

3 Emitter

You should have these results, if the transistor is good.

2SC3263 (NPN)

Positive lead Negative lead Result

B C Conductive

B E Conductive

C B Infinite

C E Infinite

E B Infinite

E C Infinite

2SA1294 (PNP)

Positive lead Negative lead Result

B C Infinite

B E Infinite

C B Conductive

C E Infinite

E B Conductive

E C Infinite

1 2 3 4 5 6 7 8 9 10 11 12 13 ... 23 24

Keine Kommentare

Classe Audio CAV-180 Wartungshandbuch Seite 8