Hey guys can you please help me determine whats wrong with my tda7377 chipamp when i have it on with bare circuit speakers connected its silent but when i connect any audio cable one of the channels have 50 hz tone witch is quite annoying how do i resolve it?
Im not sure if its the right section but can anybody please help me regarding my issue i really dont wanna deal with the 50hz tone playing when i want silence
Im not sure if its the right section but can anybody please help me regarding my issue i really dont wanna deal
with the 50hz tone playing when i want silence
How about if you insert shorting plugs in both inputs, is there still hum?
Can you post the schematic and a photo?
Ok if i short buzzing signal to the ground it gets a little bit qmore quiet but than the silent channel starts to buzz if i short both channels together the silent shannel pops and remain silent. If i desolider the input wire both channels are quiet if i touch the input it react like normal and start to buzz 50hz as long as i touch either of the channel. It wasnt a case until i replaced the chip last one died when i touched back of the pcb.
Circuit diagram is here
Simple Amplifier Stereo HiFi Circuit with TDA7377_Circuit Diagram World
The photos of real amp pcb is here
Postimage.org / gallery - IMG 20160124 235453, IMG 20160124 235508, IMG 20160124 235522
Circuit diagram is here
Simple Amplifier Stereo HiFi Circuit with TDA7377_Circuit Diagram World
The photos of real amp pcb is here
Postimage.org / gallery - IMG 20160124 235453, IMG 20160124 235508, IMG 20160124 235522
Ok if i short buzzing signal to the ground it gets a little bit qmore quiet but than the silent channel starts to buzz if i short both channels together the silent shannel pops and remain silent. If i desolider the input wire both channels are quiet if i touch the input it react like normal and start to buzz 50hz as long as i touch either of the channel. It wasnt a case until i replaced the chip last one died when i touched back of the pcb.
If it started when the chip went bad, check all the solder joints, then the tantalum/electrolytic capacitors.
It wasnt a case until i replaced the chip last one died when i touched back of the pcb.
If it started when the chip went bad, check all the solder joints, then the tantalum/electrolytic capacitors.
If it started when the chip went bad, check all the solder joints, then the tantalum/electrolytic capacitors.
Thanks for the reply. How do i check the caps? I only have a value digital multimiter with out capacitance check option. Further more at the time i bought those caps i didnt know the leaguer caps are the worst quality brand
Thanks for the reply. How do i check the caps? I only have a value digital multimiter
with out capacitance check option. Further more at the time i bought those caps
i didnt know the leaguer caps are the worst quality brand
I'd just replace the polarized caps, one at a time. The others are likely ok.
I'd just replace the polarized caps, one at a time. The others are likely ok.
I reccon you know more than me in electronics im looking forward to learn more about analog electronics in general.
Can you tell me what c8 do is it some kind of filtering maybe this could be the issue? But if it is it should affect all channels so there is only film caps left witch could affect one of the channels right?
I'd just replace the polarized caps, one at a time. The others are likely ok.
Thanks for your replies chnging c8 resolved the issue
I reccon you know more than me in electronics im looking forward to learn more about analog electronics in general.
Can you tell me what c8 do is it some kind of filtering maybe this could be the issue? But if it is it should affect all channels so there is only film caps left witch could affect one of the channels right?
It's SVR, supply voltage rejection (filtering).
Thanks for your replies chnging c8 resolved the issue
Great, congratulations.
I'd just replace the polarized caps, one at a time. The others are likely ok.
Thanks for your replies chnging c8 resolved the issue
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