Problem with tda2030a+tip41/tip42 120w amp

[rrbadrike]

I build power amp using 2 ic TDa2030+2 transistor TIP41+2 transistor TIP42 but when i turn the power on it gives big hum.I can't understand what should be the problem.I checked the all connection in the circuit.But there is same problem occurs.Please anybody give me solution or correct circuit diagram.This is circuit diagram which gives problem.

[tiefbassuebertr]

Such effects are always an Indicator for one or more fatal errors. Especially by this circuit you need an absolutely perfect mass/GND management. This means, you need two complete independend power supplies and power transformers for both channels.
I recall to a German magazine where this amp was describted. Check out at first step this circuit diagram, whether there are differences (see attachement)

[sakis]

fatal errors .....

[rrbadrike]

when i build the 30w amp using tda2030a+2 transistors tip41/tip42,it worked properly but when i build the amp bridge version it does not work properly .so if i replace transistor tip41/tip42 instead of bd249/bd250 in your schematic will it work proper.my single version 30w scematic is below.

[sakis]

for starts the first "fatal error" is the amplifier its shelf .... ..expected power of this amplifier of 200W is only theoretical and even with perfect tranistors, power supply , wiring , cooling , and construction could be achived for a moment as a peak power ...

bridge amplifiers will only perform the best if both parts of the bridge are equal ...if not will not work properly

then again if your original target is the power of 200W this will never make it ...add that sound that will come out of it will be terrible from every aspect ( speed , bandwidth ,ends ) and your picture is now complete

regards sakis

[Mooly]

Disconnect the speaker and measure the DC volts across the speaker output (pin 4 to pin 4). It should be below 100mv. If it's not you have a construction error or fault.

[exflaco]

The 2,2k resistor to ,22uf and work fine, tested