A while back I bought a cheap Chinese TDA 7294 mono amp board off Aliexpress to make a powered speaker simply because it would run off the existing toroidal transformer I had at the time. I am pleased to say it still works great.
Now I've got another toroidal from another dead amp which says it's a PM42E-240v. I'd like to make another powered speaker if I could, somewhere in the region of 100w mono. I can't find any information about this transformer but it's basically got two different outputs, one that's yellow wires 26-0-26 at 1.92a and another section that's blue wires 19-0-19 at .48a that I'd probably just ignore.
Now, to me this 26v sounds a bit suspect at only 1.92a but maybe I can use it for something. Just wondering what sort of similar amp boards out there (cheap) might be the sort of thing to use with this transformer.
Now I've got another toroidal from another dead amp which says it's a PM42E-240v. I'd like to make another powered speaker if I could, somewhere in the region of 100w mono. I can't find any information about this transformer but it's basically got two different outputs, one that's yellow wires 26-0-26 at 1.92a and another section that's blue wires 19-0-19 at .48a that I'd probably just ignore.
Now, to me this 26v sounds a bit suspect at only 1.92a but maybe I can use it for something. Just wondering what sort of similar amp boards out there (cheap) might be the sort of thing to use with this transformer.
+-26 v is LM1875 IC territory. 30 W max unfortunately.
Goes with the 1.92 A, 2^2=4*8ohms=32 watts.
The +-19 is useful for making +-15 for op amp input circuits.
No money, no glory.
Goes with the 1.92 A, 2^2=4*8ohms=32 watts.
The +-19 is useful for making +-15 for op amp input circuits.
No money, no glory.
Sorry but both are wrong.
Rail voltage is 1.4142 x secondary voltge so we are talking +/- 36V rails, absolutely impossible to use LM1875 with such high voltage.
I suggest the OP to get another TDA7294 board which will be very happy with such rails and provide some 60W RMS into 8 ohms.
Nice and useful project.
Rail voltage is 1.4142 x secondary voltge so we are talking +/- 36V rails, absolutely impossible to use LM1875 with such high voltage.
I suggest the OP to get another TDA7294 board which will be very happy with such rails and provide some 60W RMS into 8 ohms.
Nice and useful project.
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