DC Protection

[Xavier]

Guys, I'm looking for some good DC Protection circuits. I have built a muting relay circuit which is a part of preamplifier circuit that appeared in Electronics World. This included turn-on muting and immediate relay de-enegrgizing at turn-off and power-failure. The circuit works excellent, but it has no DC Protection or Thermal Over-Load Protection built-in(coz its a part of a preamplifier circuit), so I'm looking for a DC Protection which might serve as an add-on to the existing circuitry. I beleive that this part also appeared in Electronics World. Your kind help is needed.

Thanks

- XL

PS: I don't want to use a thermal switch for protection.

 

[paulb]

Check out Projects 33 and 46 at http://www.sound.au.com/index.html

 

[Koy]

I have just finished one. When DC offset is higher than about 2.5V the output relay switches the speakers off. If you are interested I can send the shematics. Very simple. Needs +-15V supply ( or about). You can use the email.