Reducing transformer voltage...

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Hi !

This resistors to drop voltage shoud be huge .You need 150 V drop , and 250 mA , it is a lot of power and temperature - 37,5 W per each branch . Make sure so you have proper cooling . Resistor should have 600 ohm , if of course you need this 250 ma . How much of current You need to provide for application powered by this tran ?

Values of this transformer are telling me it's a power supply for tube amp , and I not reccomend any such big resistor reductions in main supply voltage because of voltage swing which depends from anode and other changing currents . Power supp should not to swing voltages . Revinding this tran is a better solution , I think .

:)
 
Will you be using the 5v winding? If not you could use a 30 to 36v
transformer to "buck" your line voltage. But your 5v will also be
reduced to about 3.8v.... but if you only needed 5v at 2A you
could send the 3.8v through a schottky rectifier bridge and cap
to get ~4.8v
 
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