I ran the first tests of a new thermal vacuum chamber. It's a stainless steel can with vacuum and cable ports. The can fits inside a plastic ice chest that can be packed with dry ice (see my Nuts and volts article on this subject).
The front of the chamber is sealed with thick acrylic plastic to permit observations of the interior of the chamber during testing. The cable port permits power to enter the chamber for its ultraviolet source and temperature sensor. Pressure inside the chamber is monitored with an analog pressure gauge.
I call the thermal vacuum chamber, Near Space in a Can. It's the second simulator NearSys will sell (the GPS simulator is the first). Near Space in a Can is large enough to test BalloonSats and CubSats.
Near Space in a Can will be available from NearSys in 2011 as an affordable kit.