Well, here are some of my measurements:
U17
Pin 1: 0
pin 2: 0
pin 3: 0
pin 4: -9.91
pin 5: 0
pin 6: 7.90
pin 7: 9.76
pin 8: 0
U5
Pin 1: 0
pin 2: 7.90
Pin 3: 8.15
pin 4: -9.91
pin 5: -0.40
pin 6: 8.23
pin 7: 9.76
pin 8: -0.93 and this measure ranged
U5 can be wrong?
U17
Pin 1: 0
pin 2: 0
pin 3: 0
pin 4: -9.91
pin 5: 0
pin 6: 7.90
pin 7: 9.76
pin 8: 0
U5
Pin 1: 0
pin 2: 7.90
Pin 3: 8.15
pin 4: -9.91
pin 5: -0.40
pin 6: 8.23
pin 7: 9.76
pin 8: -0.93 and this measure ranged
U5 can be wrong?
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U11
pin 1: -8,04
pin 2: 0
pin 3: 1,67
pin 4: -9,90
pin 5: 0
pin 6: -7,15
pin 7: 8,16
pin 8: 9,76
pin 1: -8,04
pin 2: 0
pin 3: 1,67
pin 4: -9,90
pin 5: 0
pin 6: -7,15
pin 7: 8,16
pin 8: 9,76
Okay, but this IC, I have not, I will order more parts, take me to come, eight or ten days.
Thanks for everything, Perry, and when I get the parts, I will tell what happens ...
Thanks for everything, Perry, and when I get the parts, I will tell what happens ...
Well, today I arrived I was missing the IC (LM6172)
This is what happens when connected:
The first thing to say that the amplifier is stable, even when loaded in the output and input signal.
The speaker produces hissing, (0.7 v at terminals)
When I connect the audio signal at the entrance, distorted sound on the speaker, and bass, as if it ran only 15% of its performance.
When you turn the gain level, the hissing sound changes, there is even a point at which almost disappears.
When I switch the switch on the stage, the speaker cone gives a blow.
I think the amp works, but must have a fault in the previous section ...
What do you think Perry?
This is what happens when connected:
The first thing to say that the amplifier is stable, even when loaded in the output and input signal.
The speaker produces hissing, (0.7 v at terminals)
When I connect the audio signal at the entrance, distorted sound on the speaker, and bass, as if it ran only 15% of its performance.
When you turn the gain level, the hissing sound changes, there is even a point at which almost disappears.
When I switch the switch on the stage, the speaker cone gives a blow.
I think the amp works, but must have a fault in the previous section ...
What do you think Perry?
No, sorry, must be my translator
I refer to the phase switch (0-180) which when I move it, produces a thump sound from the speaker....
I refer to the phase switch (0-180) which when I move it, produces a thump sound from the speaker....
Do any of the op-amps in the preamp section have more than 0.01v difference between the inverting and non-inverting inputs? For 2-channel op-amps, check both sections of the op-amp.
Okay, I'll check this afternoon.
This measure, I always do, with the black test negative ground of the amplifier, right?
O refers to a probe on pin 2 of the TL072, and the other probe on pin 3 of TL072?
This measure, I always do, with the black test negative ground of the amplifier, right?
O refers to a probe on pin 2 of the TL072, and the other probe on pin 3 of TL072?
Well, I have the measures
Multimeter's negative probe connected to the amplifier negative
U1 U2 and U3, the three have the same voltage
pin 2: 0.68
Pin 3: 0.67
pin 5: 0.67
pin 6: 0.68
U4 here changes the voltage
pin 2: 0.35
Pin 3: 0.35
pin 5: 0.67
pin 6: 0.67
Multimeter's negative probe connected to the amplifier negative
U1 U2 and U3, the three have the same voltage
pin 2: 0.68
Pin 3: 0.67
pin 5: 0.67
pin 6: 0.68
U4 here changes the voltage
pin 2: 0.35
Pin 3: 0.35
pin 5: 0.67
pin 6: 0.67
U4
Pin 1: 0.02
pin 2: 0.35
Pin 3: 0.34
pin 4: -9.91
pin 5: 0.67
pin 6: 0.67
pin 7: 0.67
pin 8: 9.78
U17
Pin 1: 0
pin 2: 0
Pin 3: 0
pin 4: -9.91
pin 5: 0
pin 6: 5.68
pin 7: 9.79
pin 8: 0
Pin 1: 0.02
pin 2: 0.35
Pin 3: 0.34
pin 4: -9.91
pin 5: 0.67
pin 6: 0.67
pin 7: 0.67
pin 8: 9.78
U17
Pin 1: 0
pin 2: 0
Pin 3: 0
pin 4: -9.91
pin 5: 0
pin 6: 5.68
pin 7: 9.79
pin 8: 0
Those look OK but the 5+v on the output of U17 seems to indicate that there is a problem in the driver circuit.
Do you have the DVD tutorial?
Have you found a scope yet?
Do you have the DVD tutorial?
Have you found a scope yet?
Can't remember if this was covered but you did check both MIC4420CT mosfet drivers to confirm they were ok?
Perry:
No, I have the dvd tutorial, where I can buy?
The oscilloscope, I'm still looking for here, my city, I can rent one, but can not find ...
Seankane:
I ... you're right, the U10, I have not checked, this afternoon when I get home, I will post the measurements of all the pins ...
I really appreciate the effort and consideration you're having me.
No, I have the dvd tutorial, where I can buy?
The oscilloscope, I'm still looking for here, my city, I can rent one, but can not find ...
Seankane:
I ... you're right, the U10, I have not checked, this afternoon when I get home, I will post the measurements of all the pins ...
I really appreciate the effort and consideration you're having me.
I'm not trying to sell the DVD here (the mods wouldn't approve). I was asking because I was going to point you to a particular section.
If you don't find that the driver is defective, maybe seankane can point you to the repair where a pot was used to cause the amplifier to swing high or low and allow the drive circuit to be tested with a multimeter.
If you don't find that the driver is defective, maybe seankane can point you to the repair where a pot was used to cause the amplifier to swing high or low and allow the drive circuit to be tested with a multimeter.
Sorry Perry, I did not mean to bother you, I read all your links ...
In my previous message, when I said, I really appreciated the effort and consideration that was on your part, I meant the two,
Sorry also for my translations (Spanish to English), that maybe sometimes not well understood ..
In my previous message, when I said, I really appreciated the effort and consideration that was on your part, I meant the two,
Sorry also for my translations (Spanish to English), that maybe sometimes not well understood ..
Well, U10 measures are:
pin1, pin2, pin3,pin4 and pin5 are all the same, ranging between 11.00 and 10.70 v
I checked, U6 and I make, the same measures as U10
Today when connecting the amplifier I've noticed something strange ...
The LED protection has not been on for a second, as before ...
After doing these steps I have said, I connected the speaker, and after five seconds, Q105 has blown, ¿weird?
pin1, pin2, pin3,pin4 and pin5 are all the same, ranging between 11.00 and 10.70 v
I checked, U6 and I make, the same measures as U10
Today when connecting the amplifier I've noticed something strange ...
The LED protection has not been on for a second, as before ...
After doing these steps I have said, I connected the speaker, and after five seconds, Q105 has blown, ¿weird?
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