Would a ba 494 cuase the amp to do this..
If all outputs are out of the amp the power light will come on and stat lit also the amp will idle fine...
If i put the outputs in the amp the power light will slowly dim down and shut off...
I triple checked all of the outputs and drivers for the outputs and all test fine..
If all outputs are out of the amp the power light will come on and stat lit also the amp will idle fine...
If i put the outputs in the amp the power light will slowly dim down and shut off...
I triple checked all of the outputs and drivers for the outputs and all test fine..
amp did it before when i first got it but the problem went away i thought i had it fixed but it came back
Install the outputs in each channel, one channel at a time to see if it's the left or right channel that's causing the problem.
i would personally check what is being driven to the outputs and drivers, both at idle, and with a tone, if you have it idling/assembled with no outputs installed.
all 4 of theese diodes are shorted they read 0.000 in both directions out of the board..
They are 1N4004 would the 1N4003's work ?
They are 1N4004 would the 1N4003's work ?
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see post above also it doesnt matter what channel i have the outputs in the light will slowly fade and turn off..
This amp uses C5200's and A1943's as the outputs..
If i only stick 1 output in the amp doesnt matter what side the amp goes dead
This amp uses C5200's and A1943's as the outputs..
If i only stick 1 output in the amp doesnt matter what side the amp goes dead
Reinstall the outputs and post the DC voltage on the TL494 an the 8-pin op-amp near it after the amp shuts down.
After the amp shuts off this is what i have..
TL494
Pin 1:0.19
Pin 2:4.98
Pin 3:4.74
Pin 4:0.08
Pin 5:1.48
Pin 6:3.45
Pin 7:0
Pin 8:13.90
Pin 9:0
Pin 10:0
Pin 11:13.90
Pin 12:13.16
Pin 13:4.98
Pin 14:4.98
Pin 15:4.98
Pin 16:11.16
JRC2904
Pin 1:0
Pin 2:12.38
Pin 3:6.52
Pin 4:0
Pin 5:11.69
Pin 6:4.98
Pin 7:11.77
Pin 8:13.16
TL494
Pin 1:0.19
Pin 2:4.98
Pin 3:4.74
Pin 4:0.08
Pin 5:1.48
Pin 6:3.45
Pin 7:0
Pin 8:13.90
Pin 9:0
Pin 10:0
Pin 11:13.90
Pin 12:13.16
Pin 13:4.98
Pin 14:4.98
Pin 15:4.98
Pin 16:11.16
JRC2904
Pin 1:0
Pin 2:12.38
Pin 3:6.52
Pin 4:0
Pin 5:11.69
Pin 6:4.98
Pin 7:11.77
Pin 8:13.16
A transistor (A1015) transistor is connected to pin 5 Also a 33K ohm resistor it measures 33.14k ohms
Heres the voltages on the A1015 transistor
Emitter:13.14
Collector:11.70
Base:13.15
Not sure if its defective or not buy if it appears to be Is there a good Sub?
Heres the voltages on the A1015 transistor
Emitter:13.14
Collector:11.70
Base:13.15
Not sure if its defective or not buy if it appears to be Is there a good Sub?
Remove that transistor. Does that allow the amp to remain on?
Desolder the 33k ohm resistor connected to pin 5. Does that allow the amp to remain on?
Be careful. If the output transistors are in the circuit, it may draw excessive current.
Desolder the 33k ohm resistor connected to pin 5. Does that allow the amp to remain on?
Be careful. If the output transistors are in the circuit, it may draw excessive current.
If i pull the 33ohm resistor or the Transistor the amp will protect and the power light still goes out
Yes the only thing that changes is pin 5 of that op-amp the voltage jumps around now and if i leave my meter probe on pin 5 the amps torriod hiss's but the power light remains on
Hi,
I think if the rails voltage it is OKAY then there is not a problem with 494 since the rail voltage are withing limits. Now I would check the gate or the base of all output transistors to see if there it is a problem with the drivers. If they all read zero or close to zero then the problem it is in the output transistors. The protection it is coming in because it is possible that it is detecting high voltage going to the speakers. That it is what it suppose to do. Check the base or the gate voltages it will tell you where it is the problem and post the read voltages.
I think if the rails voltage it is OKAY then there is not a problem with 494 since the rail voltage are withing limits. Now I would check the gate or the base of all output transistors to see if there it is a problem with the drivers. If they all read zero or close to zero then the problem it is in the output transistors. The protection it is coming in because it is possible that it is detecting high voltage going to the speakers. That it is what it suppose to do. Check the base or the gate voltages it will tell you where it is the problem and post the read voltages.
Ok with the resistor put back into circuit but the transistor out of circuit the amp remains powerd up and idles fine
Is the transistor defective?
Are the outputs in the circuit?
Does it produce clean audio from both channels?
Are the outputs in the circuit?
Does it produce clean audio from both channels?
With that out of circuit the left channel plays clean audio..
The right channel has issues I have 40 volts of rail on the speaker terminals..
The 150 ohm resistor that connects between the drivers (Tip31c Tip32c)
Keeps burning up..
I checked both drivers all of the outputs and every transistor in the right channel everything tests fine..
With all outputs removed from the right channel the amp will still burn the 150 ohm resistor within 3 secs..
Any ideas what may cause this???
Ive checked all transistors checked for solder bridges and still cant fine the fault
The right channel has issues I have 40 volts of rail on the speaker terminals..
The 150 ohm resistor that connects between the drivers (Tip31c Tip32c)
Keeps burning up..
I checked both drivers all of the outputs and every transistor in the right channel everything tests fine..
With all outputs removed from the right channel the amp will still burn the 150 ohm resistor within 3 secs..
Any ideas what may cause this???
Ive checked all transistors checked for solder bridges and still cant fine the fault
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