How do you make an efficient transmitter? If I wanted to send out a 1khz sine wave, couldn't I just use a function generator and a wire, sending the AC current through the wire? It seems to me that, in order to transmit even a small signal, you'd have to waste a LOT of energy to heat. Do you want to use really high voltage with low current OR really high current with low voltage to generate strong signals without a lot of wasted heat? How would I build a transmitter? Are transmitters connected in series to the rest of the circuit, or is it like an antenna, just floating? How do you increase/decrease the power to your transmitter and how do you measure it's strength and load on the circuit?
What's the rule for running LEDs at much higher voltages than rated, but with series resistors? You effectively can draw less current but still use the same wattage/power. Is LED brightness dictated by the power or current? At higher voltages, if it's the current that matters, wouldn't there have to be more waste heat? Theoretically, could you run an LED on 10,000 volts+ with very little current?
Lastly, do motors work more efficiently at higher voltages and lower current? If so, why? What sort of loads can you safely use the higher voltage with limited current scheme in general?
What's the rule for running LEDs at much higher voltages than rated, but with series resistors? You effectively can draw less current but still use the same wattage/power. Is LED brightness dictated by the power or current? At higher voltages, if it's the current that matters, wouldn't there have to be more waste heat? Theoretically, could you run an LED on 10,000 volts+ with very little current?
Lastly, do motors work more efficiently at higher voltages and lower current? If so, why? What sort of loads can you safely use the higher voltage with limited current scheme in general?