TDA7265 Humming

[aditya]

hiii
i had used this amp earlier but now when i rebuilt it is sort of humming when no input is give and volume is at max, ( speaker kept next to ear)

and i ahve toriod transformer , 2 4700/35v caps per rail and 104 poly cap on the ic about 4 mm away frompin
posted the pcb, it is made as per the datasheet only change is i dont have mute circuit and my feed back resistor for gain are on the tother side complared to datasheet

help needed

 

[Minion]

So with No input and the Vol at max it hums ?? I haven"t played with many amps that didn"t hum with the Vol at max with no input , I believe it is normal .....

 

[aditya]

after taping thing and tie it and doing twisted wire's its gone silent. will post pic shortly

 

[lanchile]

after taping thing and tie it and doing twisted wire's its gone silent. will post pic shortly

Good to hear that! I bet you had a big antenna with all the wires lol.
yeah, we need pictures!

 

[aditya]

Good to hear that! I bet you had a big antenna with all the wires lol.
yeah, we need pictures!

hi here are some pictures of the amplifier

 

[mjf]

hello.
......it looks like there is a preamp on the backside.........it is built in near the big transformer.......that could cause the humming.
greetings

 

[aditya]

i'm not aware if toroid,s caused any hum but now the hum's gone and that pre needs a micro controller to use. Which is not installed yet. And i'm giving it direct input to amp