DS18 Amp

[caraudioguy2100]

Well amp is powered up and idles fine .

Now the issue is no output.

This is what I get on the gate leg for the outputs so I’m assuming it’s producing rail to rail oscillation

Scope set to 5 us 5 volts div

 

[Perry Babin]

Check on the input side of the output filter inductor to see if it's producing r-r oscillation.

 

[caraudioguy2100]

This is the input side of the output inductor

 

[Perry Babin]

Are you driving a signal into the amp?

 

[caraudioguy2100]

No

 

[Perry Babin]

Self-oscillating amps often need an input signal to start the output stage oscillating.

 

[caraudioguy2100]

I drove a signal into the amp also and still no output

 

[Perry Babin]

Did you see a rail-rail signal on the input of the inductor?

What's the rail voltage in this amp?

 

[caraudioguy2100]

I saw rail to rail on the input side of the inductor .

The rail voltage is 117 volts

 

[caraudioguy2100]

Ok I found a burnt resistor by the audio driver board replaced it now I get -167 volts across the speaker terminals.

Any ideas what might cause this ?

 

[Perry Babin]

You're going to have to wait for someone with a diagram of a similar amp. I have no clue what resistor you replaced or what driver board it uses.

Does this amp have a bridged output?