2008 Espec EV21 Altitude chamber with Oerlikon SV25 vacuum pump (2008)

interior dimensions 35"x35"x30"h

Altitude performance to 15,000ft within 20 minutes

Altitude programmer Watlow F4 with RS232

11"x11" viewing window

460v, 3ph, 60hz, 15amps

Oerlikon SV25B vacuum pump ultimate vacuum 1 torr

1 torr corresponds roughly to 260,000 ft

100 torr corresponds roughly to 49,000 ft

Although the chamber has been specified as rated to 15,000 ft. for the customer application it is able to withstand considerably higher vacuum levels.

The chamber was purchased by Western Digital to test read/write heads on disk drives at higher elevations. (Read/write heads are tiny sensors on the end of an actuator arm that fly nanometers above spinning hard disk platters to read/write data using electromagnetism. They detect magnetic fields (reading) and alter magnetic polarity (writing). 

3610 hours