Hi all,
received this amp in this condition, it is in protection.
can someone assist with a schematic please?
PSU has IRFP2907 & IRFP064N
Outputs are IRF640 & IRF9640
received this amp in this condition, it is in protection.
can someone assist with a schematic please?
PSU has IRFP2907 & IRFP064N
Outputs are IRF640 & IRF9640
Last edited:
Hi Perry,
Yes. There are no shorted mosfets. I pulled the rectifiers and psu seems to work. I get + 63 and - 63 rails. I stopped there.
Yes. There are no shorted mosfets. I pulled the rectifiers and psu seems to work. I get + 63 and - 63 rails. I stopped there.
Hi,
I removed the outputs and installed the rectifiers, amp relay engages but i don't have any rail voltage. Could the rectifiers be defective?
I removed the outputs and installed the rectifiers, amp relay engages but i don't have any rail voltage. Could the rectifiers be defective?
What do you read if you measure the DC voltage across the output terminals of each of the two PS filter inductors?
I was sure I saw 63v on the dso scope when i probed the centre leg traces of the rectifiers... I could have been wrong
The rectifiers needed to be in the circuit when you measured the voltage on the inductors. Were they?
The voltage was likely from charged rail caps.
What's the resistance between the negative speaker terminal and the primary ground terminal?
What's the resistance between the RCA shields and the primary ground terminal?
The voltage was likely from charged rail caps.
What's the resistance between the negative speaker terminal and the primary ground terminal?
What's the resistance between the RCA shields and the primary ground terminal?
It appears that there is some conflicting information. Measure the voltages in the next few posts without making any changes. Have all components in the circuit.
What is the DC voltage on terminals 9 and 10 of the PS driver IC?
What is the DC voltage on terminals 9 and 10 of the PS driver IC?
With rectifiers installed - TL494 pin 9 & 10: 0.3v
without rectifiers - TL494 pin 9 & 10: 3v (square waves on gates and drains)
without rectifiers - TL494 pin 9 & 10: 3v (square waves on gates and drains)
Are you saying that there is nothing but 0.3v of DC on 9 and 10? And absolutely no drive signal?