Proportional A-C power control

A control circuit connected to an alternating current source for providing smooth and continuous current regulation to connected loads comprising:

• a crossover detector for detecting the change in polarity of the alternating current source and generating a signal in response thereto,
• a timing circuit connected to said crossover detector for receiving said signal,
• said timing circuit being energized by said source for establishing an adjustable direct current reference potential and comprising a pair of capacitive means,
• one of said capacitive means functioning as a timing device and being charged by said source under the control of said signal,
• control means for receiving said signal and effecting the charging or discharging of said timing device depending on the value of said signal,
• the other of said capacitive means being charged by said adjustable reference potential and connected to said control means for preventing said timing device from discharging below a value related to said reference potential,
• whereby when said signal is relatively high said one of said capacitive means charges and when said signal drops to substantially zero it begins to discharge to a predetermined voltage value depending on the set value of said reference potential, said timing circuit generating an output signal relatively early in each half cycle of said source when said reference potential is high and generating an output signal relatively late in each half cycle when said reference potential is low.