Ok those appear correct voltages after placing black probe on ground Germaine .
How do I measure the rail voltage in this amp ?
How do I measure the rail voltage in this amp ?
Across the center legs of the two rectifiers. Don't slip. Alternatively, you should be able to touch to the tabs of the transistors.
I don't know what it is supposed to be but if it's producing rail voltage, that's probably right. I see 100v rail caps in the photos I have.
Back to this amp .
The amp has very distorted output sounds like I’m plugging the test speaker into a wall outlet .
The voltage at the speakers terminals is 0.00 so that’s not and issue .
Any ideas ?
The amp has very distorted output sounds like I’m plugging the test speaker into a wall outlet .
The voltage at the speakers terminals is 0.00 so that’s not and issue .
Any ideas ?
Post a photo of the waveform. Drive a 50-100Hz signal into the amp. Set the scope to 2ms and 5v/div. Drive the amp hard enough to make the waveform cover most of the display.
I will have to get back to you on that either the probe or the scope is no good it won’t lock on a waveform .
Unless is picking up noise or something it’s on the bottom level of my house next to my power supply
Unless is picking up noise or something it’s on the bottom level of my house next to my power supply
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If by power supply, you means the mains panel, that won't cause a problem.
Try setting the trigger to manual and adjusting the trigger level.
Can you view a power supply waveform (10us and 5 or 10v/div, depending on the point probed)?
Try setting the trigger to manual and adjusting the trigger level.
Can you view a power supply waveform (10us and 5 or 10v/div, depending on the point probed)?
Yes I can view the power supply waveform perfectly .
Wondering can mismatched outputs cause this problem in this amp ?
Wondering can mismatched outputs cause this problem in this amp ?
That won't cause it to be distorted.
Try paralleling a capacitor across the speaker terminals with your dummy load/speaker. Does that allow your scope to lock on?
Use a mylar/film cap of about 10uf if you have one. If you have to use polarized caps, connect two in series with reverse polarity (negatives together).
Try paralleling a capacitor across the speaker terminals with your dummy load/speaker. Does that allow your scope to lock on?
Use a mylar/film cap of about 10uf if you have one. If you have to use polarized caps, connect two in series with reverse polarity (negatives together).
I let this amp sit for a couple of weeks and now when I power it up it works perfectly fine .
Any ideas why it had distorted output then letting the amp sit now it works perfectly fine?
Any ideas why it had distorted output then letting the amp sit now it works perfectly fine?
Push/pull/tap/heat/cool everything to see if you can cause the problem to return. It's very rare for an amp to fix itself... reliably.
The amp will distort when first powered on but if it plays for a min the distortion goes away and the amp plays fine .
Not sure if it’s in my head unit or test sub I will try to get a pic of the waveform
Not sure if it’s in my head unit or test sub I will try to get a pic of the waveform