Can a step down toroid be reversed to a step up toroid?

Usually refers to a transformer. A step up transformer increases the voltage and a step down decreases the voltage by an amount proportional to the ratio of the windings between Primary and...

A step-up transformer is a transformer that receives its voltage lower than its output voltage (it 'steps-up ' the voltage). While a step-down transformer is a transformer that receives the voltage...

step-down transformer Transformer in which the output AC voltage is less than the input AC voltage. step-up transformer Transformer in which the output AC voltage is greater than the input AC voltage.

step up T/F increase the supply voltage while the step down transformer decrease the supply voltage

Step up increases the voltage and a step down decreases the voltage from the primary to the secondary proportional to the number of turns in each winding.