If R848 is a 3.3K resistor pin 7 connects to it..
From Pin 7 to R848 i get 0.02 ohms
On the other side of that resistor i dont not get 5 volts it remains at 0.00 volts whn trying to power the amp up the voltage never moves from 0.00
Pin 7 also connects to a 9.1K resistor and i get 0.02 ohms to pin 7 also..
The other side of that resistor the voltage remains at 0.00 volts and never changes..
The 9.1 K resistor connects to pin 8 of U801 (MM74HC02M)
Pin 8 remains at 0.00 volts..
I noticed the on that IC the pads on Pins 3 and 4 are missing off the board but all other pads are intact..
Pins 3 and 4 of that IC (U801) do not connect together do they?
From Pin 7 to R848 i get 0.02 ohms
On the other side of that resistor i dont not get 5 volts it remains at 0.00 volts whn trying to power the amp up the voltage never moves from 0.00
Pin 7 also connects to a 9.1K resistor and i get 0.02 ohms to pin 7 also..
The other side of that resistor the voltage remains at 0.00 volts and never changes..
The 9.1 K resistor connects to pin 8 of U801 (MM74HC02M)
Pin 8 remains at 0.00 volts..
I noticed the on that IC the pads on Pins 3 and 4 are missing off the board but all other pads are intact..
Pins 3 and 4 of that IC (U801) do not connect together do they?
I think that all of the logic ICs (74....) operate off of 5v and for all of them, the top left pin is 5, the bottom right pin is ground.
I think all of the pins on U801 are used.
Follow the traces back for the 5v power. Virtually every power source in these amps passes through a 10 ohm resistor before going to the IC. The resistors sometimes open.
I think all of the pins on U801 are used.
Follow the traces back for the 5v power. Virtually every power source in these amps passes through a 10 ohm resistor before going to the IC. The resistors sometimes open.
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