Well the next step if you are happy would be to turn the bias down and then try on full mains. Only if it seems OK should you re-bias to the correct value.
You also should really use a scope to make sure nothing bad is going on that you can't hear.
A 100nF cap between output and ground sound bizarre tbh. Is that on the original design?? It doesn't sound right at all. Assuming the amp survived the cap would draw several amps if you tested at high frequencies.
You also should really use a scope to make sure nothing bad is going on that you can't hear.
A 100nF cap between output and ground sound bizarre tbh. Is that on the original design?? It doesn't sound right at all. Assuming the amp survived the cap would draw several amps if you tested at high frequencies.
Yep I will remove the bulb.
I have unfortunetly not the possibility to find a scope, I know that it is really a big help, but this is dead :/
C6652 is between the GND of the output, and the backcover of the AVR.
The 100n cap is on the original design, you can see that on my post #6 :
P6601 is the ouput connector, and C6642 is the 100n cap between out and GND.
I have unfortunetly not the possibility to find a scope, I know that it is really a big help, but this is dead :/
C6652 is between the GND of the output, and the backcover of the AVR.
The 100n cap is on the original design, you can see that on my post #6 :
P6601 is the ouput connector, and C6642 is the 100n cap between out and GND.
C6652 (shown as 102) is a 1nF or 1000pF cap. That kind of thing is pretty common in lots of commercial gear to meet any tests on interference and so on.
C6642 is not 100nF. 103 is 10,000pF which is 0.01uF
C6642 is not 100nF. 103 is 10,000pF which is 0.01uF
Ouuuups sorry yes it is 10nF !
I make some measures, and I found the values indicated in the manual services at different point.
I make some measures, and I found the values indicated in the manual services at different point.
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Hello all,
some news about my project 🙂
I tested my amp with music, all seems good (but I have nothing for measure the THD or other parameters..), and with a sin signal with a Youtube "music" :
200 Hz Frequency •♕• - 10 mins - YouTube
200Hz and 1Khz.
I mounted a 40W 6R ceramic resistor on the output, and start the tests.
Multimeter displayed 25V-AC, so arround 104W, but my phone can't generate a higher signal, so I have not tested for more power.
I start 5 tests for 5min each time, because I have only 1 resistor of 40W in my hands !
No smoke, resistor is hot, and heatsink too, but all seems ok.
My multimeter is capable to measure the frequency of a signal, so I measured the frequency with 200hz and 1khz on the input, I get 199.9Hz and 999Hz, nice.
Power transistors arenot hot without signal.
Now I'm working on the MCU baord, you can see that below. I will try the board this week, and come back here for show the result 🙂
It is not the best board that you can see on this forum, but I think that all will work fine xD
The MCU is the ESP32, with a 320*240 LCD, one NJW1194 for the audio processing and a rotary with button. Only that 🙂
some news about my project 🙂
I tested my amp with music, all seems good (but I have nothing for measure the THD or other parameters..), and with a sin signal with a Youtube "music" :
200 Hz Frequency •♕• - 10 mins - YouTube
200Hz and 1Khz.
I mounted a 40W 6R ceramic resistor on the output, and start the tests.
Multimeter displayed 25V-AC, so arround 104W, but my phone can't generate a higher signal, so I have not tested for more power.
I start 5 tests for 5min each time, because I have only 1 resistor of 40W in my hands !
No smoke, resistor is hot, and heatsink too, but all seems ok.
My multimeter is capable to measure the frequency of a signal, so I measured the frequency with 200hz and 1khz on the input, I get 199.9Hz and 999Hz, nice.
Power transistors arenot hot without signal.
Now I'm working on the MCU baord, you can see that below. I will try the board this week, and come back here for show the result 🙂
It is not the best board that you can see on this forum, but I think that all will work fine xD
The MCU is the ESP32, with a 320*240 LCD, one NJW1194 for the audio processing and a rotary with button. Only that 🙂