Thank you for pointing that out, I originally had the black probe on the main NEG connection of the amp. This time I moved it to the negative spk terminal and managed to get a proper reading. For both positive rails I get +32.15V and both negative rails I get -32.00V
For the probes, I'm sure the ones mentioned are better but don't throw out the old ones. To make some measurements easier, you can solder to them to make right-angle or extended probes. You can sharpen them, when needed, to prevent having them slip.
It appears that the amp's power supply is up and running (assuming that the rail voltage is not dropping).
With your scope (use the same ground point), do you see rail-rail oscillation on the input side of the output filter inductors?
It appears that the amp's power supply is up and running (assuming that the rail voltage is not dropping).
With your scope (use the same ground point), do you see rail-rail oscillation on the input side of the output filter inductors?
True that, I'll definitely keep my old one for automotive or modify them like you mentioned.
Good to know the power supply is good at least. Seems like some tiny component has gone bad perhaps.
Regarding the inductor, that would be the big wounded one right? I'm gonna trace around to see what's the input side
The output filter inductors are the toroidal coils standing in front of the output transistors. One terminal (the input terminal) connects to the output transistor. The other terminal connects to the speaker terminal. You want to check on the input terminal of the inductors.
Ok im back, Thank you for the guidance. I did notice exactly what you said
**wanted to add that for the rail voltage measurements, the rail voltage drops when I disconnect the remote and goes back up to normal when I connect the remote back.
So I probed all 6 and got about 31Vrms at 366Khz square wave for all
**wanted to add that for the rail voltage measurements, the rail voltage drops when I disconnect the remote and goes back up to normal when I connect the remote back.
So I probed all 6 and got about 31Vrms at 366Khz square wave for all
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Have you tried to get audio from it on this 12v supply?
Out of the heatsink, watch the temperature of the transistors that are normally clamped to the heatsink.
Out of the heatsink, watch the temperature of the transistors that are normally clamped to the heatsink.
Just did, I supplied 1khz Sine wave from my phone to each channel and they all seemed to produce a fairly good 1kzh Sine wave output.
So this is weird, the amp seems to work just fine, and the red protect light just goes on when the remote is off. Maybe I should put it back on the car and see how it reacts?
So this is weird, the amp seems to work just fine, and the red protect light just goes on when the remote is off. Maybe I should put it back on the car and see how it reacts?
Is there any DC voltage on the RCA shields of the amp input RCAs?
Twist the power transformer while checking to make sure there isn't any DC. Do this with the amp on, as it is in the photo above.
When the protection LED would come on with no remote, would the LED stay lit indefinitely?
Twist the power transformer while checking to make sure there isn't any DC. Do this with the amp on, as it is in the photo above.
When the protection LED would come on with no remote, would the LED stay lit indefinitely?
To test the RCAs, should i connect the NEG probe on the outer shield and the POS probe on the inner connection and have the DMM set to Vdc ?
I believe the primary ground is the main power ground, I place my scope ground there and red on the RCA shield, and got the following reading for ch 5 & 6, did not test the rest. Twisting the large toroidal didn't seem to change the readings. ** Its been about 5min since I disconnected the remote and the red light still on
Check the others.
200mv is likely just noise. 12v DC and/or significant square wave from the power supply would be significant.
200mv is likely just noise. 12v DC and/or significant square wave from the power supply would be significant.
Done,
All other channels act the same, I did make the toroidal whine after twisting it but that's no biggie.
All other channels act the same, I did make the toroidal whine after twisting it but that's no biggie.
After reinstalling it in the heatsink, make sure each channel plays up to what the supply can handle.
I just put it all together and will test later today. Would that limit be once I get clipping on my sine wave?
The current limit of the supply would cause the 12v supply voltage to drop and the amp shut down or clip really early.
I wanted to provide some closure and a bit of a PSA. But I got my amp back and working after sending it to Mmats as I didn't have any more time to keep testing it, unfortunately. But the people at MMats were great and cut me an unexpected deal due to my history with their products.
Well, It ended up being the SG2535A PWM. According to them, they can fail after a while as in my case (my amp is from '19), and it's one of the components to go if this amp gets pushed past its limit. So that's the PSA bit -- test that PMW first and foremost on this amp (probably why its socketed. I'm gonna keep one extra handy)
They didn't mention this but I did notice a small botch update done to my board, they just moved one leg of the add-on resistor from the cap to another resistor. (Name of that IC is show on earlier pictures.)
And thank you @Perry Babin for all the help.
Well, It ended up being the SG2535A PWM. According to them, they can fail after a while as in my case (my amp is from '19), and it's one of the components to go if this amp gets pushed past its limit. So that's the PSA bit -- test that PMW first and foremost on this amp (probably why its socketed. I'm gonna keep one extra handy)
They didn't mention this but I did notice a small botch update done to my board, they just moved one leg of the add-on resistor from the cap to another resistor. (Name of that IC is show on earlier pictures.)
And thank you @Perry Babin for all the help.