Need help for amplifier - Electronic Circuits Projects Diagrams Free

ajik · 29th October 2004, 07:05 AM

hello all,
i have a problem with my amplifier. maybe somebody can help me how it can be solved.

yesterday, i'm working with my amplifier, this is the schematic.

when the power is on, i found a abnormal condition. Q5 and Q7 is very hot.

maybe somebody can tell me why it could happen and what must i do?

thanks before

zachtheterrible · 29th October 2004, 07:15 AM

4 some odd reason, your picture does not seem to be loading, try converting it to .gif . . . jpeg should work fine though.

**Nigel Goodwin** · 29th October 2004, 08:08 AM

Quote:

Originally Posted by ajik

hello all,
i have a problem with my amplifier. maybe somebody can help me how it can be solved.

yesterday, i'm working with my amplifier, this is the schematic.

when the power is on, i found a abnormal condition. Q5 and Q7 is very hot.

maybe somebody can tell me why it could happen and what must i do?

thanks before

Three things:

1) Do you have the output transistors mounted on a substantial heatsink?.

2) Have you set the bias correctly?, the preset resistor adjusts this.

3) Is the Vbe multiplier (the small transistor connected to the preset) thermally connected to the heatsink?.

If you're driving the amplifier hard the output transistors will get hot, it's why you use large transistors and big heatsinks.

zachtheterrible · 29th October 2004, 04:34 PM

WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAT!?!?!?!?!?!? WHY CAN I NOT C THIS AND EVERYONE ELSE CAN!!?!?

zachtheterrible · 29th October 2004, 04:34 PM

WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAT!?!?!?!?!?!? WHY CAN I NOT C THIS AND EVERYONE ELSE CAN!!?!?

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29th October 2004, 07:05 AM	(permalink (permalink))
ajik	Need help for amplifier hello all, i have a problem with my amplifier. maybe somebody can help me how it can be solved. yesterday, i'm working with my amplifier, this is the schematic. when the power is on, i found a abnormal condition. Q5 and Q7 is very hot. maybe somebody can tell me why it could happen and what must i do? thanks before

29th October 2004, 07:15 AM	(permalink (permalink))
zachtheterrible	4 some odd reason, your picture does not seem to be loading, try converting it to .gif . . . jpeg should work fine though. __________________ I'm no electronics god, i just talk too much.

29th October 2004, 04:34 PM	(permalink (permalink))
zachtheterrible	WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAT!?!?!?!?!?!? WHY CAN I NOT C THIS AND EVERYONE ELSE CAN!!?!? __________________ I'm no electronics god, i just talk too much.