Jake writes "When the temperature controller on my $50 garage-sale hot tub failed I balked at springing for another electro-mechanical thermostat so I built this one using junk box parts with the help of that classic: The Engineer's Mini Notebook - Op-Amp Projects from Radio Shack." Link.
HOW TO - Make an Op-Amp hot tub temperature controller
Jake writes "When the temperature controller on my $50 garage-sale hot tub failed I balked at springing for another electro-mechanical thermostat so I built this one using junk box parts with the help of that classic: The Engineer's Mini Notebook - Op-Amp Projects from Radio Shack." Link.
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Do you think this will work with a water bed (desired temp around 90 degrees F)? How close does it hold the temperature?
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It holds the temp to one degree or better, the thermometer in the tub just doesn't move. I'm sure it would work with a waterbed.
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It holds the temp to one degree or better, the thermometer in the tub just doesn't move. I'm sure it would work with a waterbed.
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