Does anyone have a schematic for this amp?
Or can tell me the value of R9908 ? It is right in front of the 494
Or can tell me the value of R9908 ? It is right in front of the 494
It's part of the regulator circuit. I would not expect it to get hot unless the negative rail is far from what it should be. Replace it and monitor the voltage on the rails as you drive a signal into the amp with a load on the amp.
I don't know if it can cause the amp to go into protect.
I don't know if it can cause the amp to go into protect.
replaced the Regulators and the 68K ohm resistor amp is still stuck in protection
The outputs test fine any idea what to check next?
The outputs test fine any idea what to check next?
I'm sorry I wasn't more specific. The resistor is part of the rail voltage regulator.
Were there any wire strands in the amp?
Did you check the outputs across all legs and not just 2-3?
Were there any wire strands in the amp?
Did you check the outputs across all legs and not just 2-3?
If you jump Q2201 collector to emitter, will the supply power up?
Be careful. Without knowing the fault, I don't know what will happen if it does power up.
Be careful. Without knowing the fault, I don't know what will happen if it does power up.
This is what i get on the 494
Pin 1:0.00
Pin 2:0.10
Pin 3:0.03
Pin 4:3.60
Pin 5:1.53
Pin 6:3.37
Pin 7:0.00
Pin 8:13.88
Pin 9:0.00
Pin 10:0.00
Pin 11:13.88
Pin 12 :13.88
Pin 13:4.98
Pin 14:4.98
Pin 15:4.98
Pin 16: 0.00
Here's what i get on the Power supply fets
Gate:0.00
Drain: 13.88
Source: 0.00
The IC isnt producing pulse's
Pin 1:0.00
Pin 2:0.10
Pin 3:0.03
Pin 4:3.60
Pin 5:1.53
Pin 6:3.37
Pin 7:0.00
Pin 8:13.88
Pin 9:0.00
Pin 10:0.00
Pin 11:13.88
Pin 12 :13.88
Pin 13:4.98
Pin 14:4.98
Pin 15:4.98
Pin 16: 0.00
Here's what i get on the Power supply fets
Gate:0.00
Drain: 13.88
Source: 0.00
The IC isnt producing pulse's
After removing R9903 the IC produces pulses but amp is still in protection mode and doesn't produce rail or regulated voltages
Do you have drive pulses on the gate legs of the 3205s?
Do you have a signal that swings from ground to 25v on the drains?
Do you have a signal that swings from ground to 25v on the drains?
I get drive pulses on the 3205's
I also get signal that swings about 25 volts volts from ground on drains
I also get signal that swings about 25 volts volts from ground on drains
How can it not have rail voltage if the transformer is being driven?
Are the rectifiers in the circuit?
Are the rectifiers in the circuit?
The rectifiers are in circuit.
The rail voltage in this amp right now is only positive 2 volts and negative 2 volts thats all i get
I just noticed R9903 is missing it sits by the 494 do you happen to know the value ?
The rail voltage in this amp right now is only positive 2 volts and negative 2 volts thats all i get
I just noticed R9903 is missing it sits by the 494 do you happen to know the value ?
Last edited:
- Status
- Not open for further replies.