Serge Auckland wrote:

"TonyL" wrote in message

I've found a couple of HY60 amplifier modules in my junk box. I have a
data sheet which indicates a +/- 25v power supply voltage rails
requirement but no indication of current. Power into 8 ohms is 30W. If I
put a power supply together what sort of current should I be expecting to
supply to each module ? Presumably, a simple dual rail
transformer/rectifier/electrolytic type of supply would be OK ?

Nice little amps!

Assuming that you're not going to be using these amps to drive some extreme
loads, then 30 watts into 8 ohms is a current of 1.94 amps, add a little for
the amp's overhead, and so you need a minimum of 2 amps per amplifier.

2 amps at +/- 25V ? That's 100W of DC per amplifier. Even run continous sinewave
it won't need that ! You're forgetting the current is shared between the + and -
rails.

1 Amp at + and - 25V per amp would do very adequately even for continuous
sinewave duty.

Graham

p.s don't forget to derate the transformer VA rating for the non-sinusoidal
currrent draw. Allow an ~ extra 30% VA over the DC watts.

Graham