for our outside dog, we used a ceramic light fixture for an incandescent bulb, a 5-pound metal coffee can, piece of three quarter inch plywood little more than a foot Square, ( to be used as the base) coat the inside of the metal can with flat black paint. drill about a hundred 1/8 inch holes in the can. Mount Your ceramic fixture at the center of the board, wiring it Through the Wood. invert the can, Center it on the light fixture, and secure it to the wood with a small hinge on one side and a hook and eye closure on the other. 4 pan head screws on the underside act as levelers.
the size of the bulb determines the amount of a heat output. 60-100wt was plenty for an Ohio winter. ( used in the normal wood dog house)

An unemployed Jester, is nobody's Fool.

the only real difference between a good tracker and a bad tracker, is observation. all the same data is present for both. The rest, is understanding what you're seeing.

~Molɔ̀ːn Labé Skýla~