| mike49504 |
| hi im working on a kenwood amp kac 7202 and checked all the outputs the test fine amp turns on but the red light stays on all the time its in protecion mode what do i check next or how do i get it out of protection |
|
|
| sdoom |
| wasn´t kenwood using the green light for ptotection ? I remember on my KAC-823 and KAC-1023 the red light indicated normal operation.... |
|
|
| mike49504 |
| yeah im sorry the red light means its fine but the red light shuts off almost instantly meaning its going into protection wondering what else i check |
|
|
| sdoom |
Are all power transistors in the music-output section ok ? Usually you can test this with an ohmmeter when the amp is off. Check for shorts between the power transistor legs.
Usually there are always two transistors belonging to one channel, one is an NPN , the other the PNP transistor, on both types usually the center leg is the collector. Try to check resistance between the two collectors , if there´s always a short there might be broken power transistors or faulty rectifier diodes in the power supply section.
Also try to check resistance of each collector to speaker GND , again ther e must be no short there. |
|
|
| mike49504 |
| thanks for your help it had a blown transistor on the left channel replaced it and works fine thanks again |
|
|
|
