There are several types of load boxes, some as expensive as a decent amp. The ones I use are called an L-pad. Basically a rheostat and a large wattage resistor. Not everyone likes them but, they are economical and work well if you use them within reason.
There are several types of load boxes, some as expensive as a decent amp. The ones I use are called an L-pad. Basically a rheostat and a large wattage resistor. Not everyone likes them but, they are economical and work well if you use them within reason.