Yes, it does.
Just plugged in my 1ohm resistor bank, and pulled around 10a of PS current at 14.4v for about 1 minute.
A clean 50Hz sine wave is going to the resistor bank.
Just plugged in my 1ohm resistor bank, and pulled around 10a of PS current at 14.4v for about 1 minute.
A clean 50Hz sine wave is going to the resistor bank.
Earlier, the 393 close to the transformer didn't appear to be causing the problem. Check it again, does pin 1 change when you sweep from low to high voltage (to where it went into protect)?
While playing an audio signal on the resistor bank?
On idle, it is just a tiny bit
At 10v, the voltage on pin 1 is 4.68v
At 11v, the voltage on pin 1 is 4.75v
At 12v, the voltage on pin 1 is 4.88v
At 13v, the voltage on pin 1 is 5.00v
On idle, it is just a tiny bit
At 10v, the voltage on pin 1 is 4.68v
At 11v, the voltage on pin 1 is 4.75v
At 12v, the voltage on pin 1 is 4.88v
At 13v, the voltage on pin 1 is 5.00v
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Previously, you stated that it had to be over 13.2 to go into protect. What happens to pin 1 at near 14v?
Is pin 16 still going high, shutting the amp down at high voltage?
Is either pin 1 or 7 of the other 393 changing at higher voltages?
Is either pin 1 or 7 of the other 393 changing at higher voltages?
Because Q14 and Q87 are removed, the amp is not going into protect at any voltage. Pin 16 stays at 0.006v when the PS voltage is 14.0v
Pin 1 LM393 at 10v is 0.11v
Pin 1 LM393 at 12v is 0.126v
Pin 1 LM393 at 14v is 0.146v
Pin 7 of the LM393 seems to be 0.1v less then the PS voltage.
Pin 1 LM393 at 10v is 0.11v
Pin 1 LM393 at 12v is 0.126v
Pin 1 LM393 at 14v is 0.146v
Pin 7 of the LM393 seems to be 0.1v less then the PS voltage.
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I only re-installed Q14, the amp is getting in protect again.
Without Q14 and Q87, pin 16 stays 0.006v, it is not burping
Without Q14 and Q87, pin 16 stays 0.006v, it is not burping
When lifting Q13, the amp is not going into protect.
Both Q14 and Q87 installed
So strange. I replaced Q13, then it powered on just fine at 14.4v. After 20sec it went into protect.
Now it always goes into protect directly after powering on (with all transistors in place).
When the amplifer has been turned on without transistor Q13 or Q14 it doesn't go in protect, If you connect Q13 it goes in protect again when the amp is at 13v
Both Q14 and Q87 installed
So strange. I replaced Q13, then it powered on just fine at 14.4v. After 20sec it went into protect.
Now it always goes into protect directly after powering on (with all transistors in place).
When the amplifer has been turned on without transistor Q13 or Q14 it doesn't go in protect, If you connect Q13 it goes in protect again when the amp is at 13v
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Thank you very much again for your help guys, I really appreciate it.
Bertje, C44, R101 (reads 10.05k) are OK. C42 fell apart when desoldering. I try to find a new 1nF SMD capacitor.
Perry, There is no TL074 in this circuit. Only a TL074C and a TL072 which are both placed on the right side of the output pwm driver card. The CT is connected to PIN 3 and 5 of the TL074c
Bertje, C44, R101 (reads 10.05k) are OK. C42 fell apart when desoldering. I try to find a new 1nF SMD capacitor.
Perry, There is no TL074 in this circuit. Only a TL074C and a TL072 which are both placed on the right side of the output pwm driver card. The CT is connected to PIN 3 and 5 of the TL074c
Look like the C42 was the problem 😀
I could not find an exact 1nF capacitor, so I replaced it with something as close to the value I could find.
The amp is powering on just fine now, no protection anymore.
It just passed some 300a of continuous current pull from the batteries at 50Hz.
Thanks for the help Perry and Bert 🙂
I could not find an exact 1nF capacitor, so I replaced it with something as close to the value I could find.
The amp is powering on just fine now, no protection anymore.
It just passed some 300a of continuous current pull from the batteries at 50Hz.
Thanks for the help Perry and Bert 🙂