Twisted Sounds 8.5k

[mnhiphop101]

Correct. Not the center leg

Yes I get rail to rail oscillation but its not at the correct frequency

No. The amp does not go into protect

 

[Perry Babin]

What frequency is it at?

 

[mnhiphop101]

76khz

 

[Perry Babin]

Only clocked amps always oscillate at the same frequency. Self-oscillating amps like these can vary in frequency and will during normal operation.

You need to find what happened between post 110 and now. Why won't the working half of the amp work like it did previously.

Could you have possibly mixed the inductor from the previously working half with the one that had a problem?

 

[mnhiphop101]

No. I decided to replace both of the so they would be the same

 

[Perry Babin]

Are you saying that the replacements are different compared to the original?

What happens if you try the original that was working perfectly?

 

[mnhiphop101]

I dont think thats the issue. I have 2 of these amps and both of them have the same issue. It appears to be a common fault with them. All I get on the speaker terminals is a triangle-ish wave. Now all of a sudden I have .7vdc on the speaker terminals. I swear things change on this amp seemingly out of nowhere.

 

[mnhiphop101]

Here's where I'm at. With one leg of each inductor pulled i installed fets on one side and powered it up. On the side with fets in I get normal operation but on the other side I see a triangle wave on the the drain of the low side.

 

[mnhiphop101]

Here's the switching wave with the inductors in.

 

[Perry Babin]

On the side with a triangle waveform, what do you get on the low-side gates?

 

[mnhiphop101]

Here's a pic

 

[mnhiphop101]

The relays close then open right away