I've seen old threads talking about electric heat sticks from Northern Brewer and other vendors - again the threads are old and I can't find these products any more. They claim they have override switches to keep them on for a full boil, to override the thermostat built in.
I want an electric stick, 120V, to stick in the wort on my gas range to help achieve vigorous boil. i bought a bucket heater:
But I didn't realize it had a safety feature, it cycles temp at boiling, I want one that stays on, also one that can work in shallower boils. This bucket heater needs probably 5 gals of water in a normal kettle, I don't think it will work at all in my 3-4 gallon boils.
I do have a 220 outlet nearby not being used (wired for electric stove, but i have gas), maybe I need to just go that route.