If I have a transformer with X number of taps on the primary side, and I have a fixed input voltage that I'd like to change the output from.
In its lowest state the two outer taps are active and the coil is whole, this is a lowest voltage output in secondary. By switching to the next tap from one end the coil is effectively shortened and the output voltage is higher. This goes on for however many taps there are.
Obviously this can be done with an array of relays, or alternatively a different set of drive transistors on each tap.
What is the best (cheapest/simplest) way I can achieve this? All ideas welcome.
Specs: ~100-200V ~20A