Thank you for your advices,
Yes, maybe a 800 VA transformer is better, right?
How do you noticed that the output was oscillating, do you have an oscilloscope?
Oscilloscopes are very expensive.
I only have them in the university and I also have the bench power supplies.
But only sometimes I can go there, they have a tight schedule.
The oscillations destroyed the output devices?
What MOSFETs are you using?
It's a good idea to add a Zener and a diode from gate to source to limit Vgs?
Best regards,
Daniel Almeida
Yes, maybe a 800 VA transformer is better, right?
How do you noticed that the output was oscillating, do you have an oscilloscope?
Oscilloscopes are very expensive.
I only have them in the university and I also have the bench power supplies.
But only sometimes I can go there, they have a tight schedule.
The oscillations destroyed the output devices?
What MOSFETs are you using?
It's a good idea to add a Zener and a diode from gate to source to limit Vgs?
Best regards,
Daniel Almeida
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I'd go with the bigger transformer.
There were a few clues to the oscillation. The first was increased current drain. The second was excess heat. the scope confirmed the presence of oscillations.
Second hand scopes are not too expensive. There is some discussion over whether a scope is needed or not but personally think you're working blind without one. A 50MHz scope is still useful. It's all I have at the moment. At least you can get access to a scope at university.
The oscillations didn't kill the output devices. Always shut the amp down if they got too hot. The L-FETs I'm using are the ECW20x20 Exicon devices.
A Gate Source zener is a good idea to protect the devices. But there is another way.
There were a few clues to the oscillation. The first was increased current drain. The second was excess heat. the scope confirmed the presence of oscillations.
Second hand scopes are not too expensive. There is some discussion over whether a scope is needed or not but personally think you're working blind without one. A 50MHz scope is still useful. It's all I have at the moment. At least you can get access to a scope at university.
The oscillations didn't kill the output devices. Always shut the amp down if they got too hot. The L-FETs I'm using are the ECW20x20 Exicon devices.
A Gate Source zener is a good idea to protect the devices. But there is another way.
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