Michael Imsic wrote: > > Roman, > > The hot box consists of two 25 watt globes fitted to a large foam > container. The globes are wired to a dimmer switch which allows me to > control the temperature. I don't need prescise regulation, more over > temp protection. For example the heating turned off at about 40 deg. C > (104F) and back on again at 20 deg. C (68F). I would love to hear about > your incubator. (changed topic to EE) Hi Michael, i'm using a wooden box about 2 cubic feet, one 100w light globe. Globe has 7% drop resistor to give globe life over hundreds of thousands switching cycles and switched by a relay at 240vac. Circuit is just 3 transistors, common collector amps each with about 10 gain, so 1000 gain total, a pot and nice large dial. Thermostat from junkbox. Adjustable from about 25'C to 55'C. Works like a charm, keeps temp within about 0.2'C of where you set the pot. We use it for curing resins and I also use it a lot for drying things, great at about 40'C. All built from junk in an afternoon. :o) -Roman -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body