Are the MPSA06/56 the drivers for the outputs or where are the drivers located ?
200 series parts .
Amp will draw excessive current when trying to power up and the outputs get hot
200 series parts .
Amp will draw excessive current when trying to power up and the outputs get hot
Rebuilt that channel .
I still have a problem with this amp .
As soon as I apply remote the amp draws excessive current .
The bias pots are set fully counter clockwise .
Any ideas ?
I still have a problem with this amp .
As soon as I apply remote the amp draws excessive current .
The bias pots are set fully counter clockwise .
Any ideas ?
It looks like D7 is blown. It's not causing the over-current but will cause engine noise.
Bias set to full CCW?
Bias set to full CCW?
Bias is set fully counter clockwise .
I replaced all of the smd diodes and transistors in that channel 200 series .
Checked every resistor in that channel as well .
That channel is still giving me
Issues with current draw
I replaced all of the smd diodes and transistors in that channel 200 series .
Checked every resistor in that channel as well .
That channel is still giving me
Issues with current draw
Measure the DC voltage across all of the 0.1 ohm source resistors. Are they all the same or do you see higher voltage on some?
I dont think it’s the channel causing the issue now .
I pulled the outputs from that channel and amp still draws 40 amps of current .
With the fet locations loaded with a 0.1 if cap here is what I get for drive signals .
Do these appear to look good ?
Also since someone tried repairing this them selfs .
Wondering if the regulators and rectifiers are in the correct locations ?
Like I said if I pull the outputs only the amp still draws 40 amps of current
I pulled the outputs from that channel and amp still draws 40 amps of current .
With the fet locations loaded with a 0.1 if cap here is what I get for drive signals .
Do these appear to look good ?
Also since someone tried repairing this them selfs .
Wondering if the regulators and rectifiers are in the correct locations ?
Like I said if I pull the outputs only the amp still draws 40 amps of current
Attachments
Those look OK.
The 3082 diagram I have only shows the output stage.
Compare your amp to the attached diagram.
The 3082 diagram I have only shows the output stage.
Compare your amp to the attached diagram.
Ok I think the regulators may be in the wrong locations .
How do I determine which one goes where ?
On another amp the 337 sits next to the negative regulator in this amp it’s sitting next to the positive regulator .
But like I said the amp has been worked on before
How do I determine which one goes where ?
On another amp the 337 sits next to the negative regulator in this amp it’s sitting next to the positive regulator .
But like I said the amp has been worked on before
What is the voltage on the input pins? The positive regulator will have a positive voltage on the input.
I'd use new regulators if they were connected to the wrong rails.
I'd use new regulators if they were connected to the wrong rails.
I replaced the power supply fets , regulators and rectifiers
The 317 has positive voltage on leg 3
337 has negative voltage on middle pin
Checked all of the outputs out of circuit and all test fine .
540’s are on negative rail 9540’s on positive rail
Amp still draws 40 amps of current when applying remote voltage
The 317 has positive voltage on leg 3
337 has negative voltage on middle pin
Checked all of the outputs out of circuit and all test fine .
540’s are on negative rail 9540’s on positive rail
Amp still draws 40 amps of current when applying remote voltage
I did some more checking
If I leave the rectifiers in when the amp draws excessive current the outputs in both channels get hot within secs
If I remove the rectifiers the amp will not draw excessive current
If I leave the negative rectifier out the amp will power up normally
If I leave the rectifiers in when the amp draws excessive current the outputs in both channels get hot within secs
If I remove the rectifiers the amp will not draw excessive current
If I leave the negative rectifier out the amp will power up normally
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