The 810th, like many other SAGE radar installations, had a Burroughs AN/FST-2 Coordinate Data Transmitting Set (CDTS). This was a huge Cold War military computer system using vacuum tubes. These computers were installed at SAGE radar stations for displaying aircraft tracks and converting them for digital transmission to air defense data centers.
The AN/FST-2 processed the raw radar data, antenna position information, and IFF data, and sent it over voice grade toll phone lines at 1200 baud (bits/second). The transmissions were received at SAGE Direction Centers, which performed the aircraft control and warning operations and provided command information to Command Centers which forwarded data to the NORAD command center in Colorado, and the Cheyenne Mountain Complex.
As one of the 810th's Refrigeration and Air Conditioning techs, one of my responsibilities was to ensure the twin T-2s remained cool. To that end there was an adjacent machine room containing two 40 ton A/C systems, one primary and one back up. Both systems were different for some reason. One used a Trane compressor and the other an older Worthington. The conditioned air was forced through ducts under the floor which terminated in outlets at the bottom of each cabinet.
If either T-2 was shut down for maintenance or any other reason those cabinets would quickly become refrigerators. If the A/C ever failed while the T-2s were running it would be a matter of just a few minutes before you could detect the scent of burning circuit boards. That was something we never wanted to have happen though it did a couple of times. We would get a call and would respond immediately, day or night.
A Honeywell temperature and humidity chart recorder sat outside the machine room, keeping track of conditions 24/7. When the chart paper ran out I or one of the other technicians would be required to replace it. The old chart would then be shipped off to head quarters some place so they could keep tabs on the system's performance.
One of many cards packed into those grey cabinets, this card, containing four dual triode vacuum tubes, made up four digital flip flop circuits. Those tubes were a militarized version of the popular 12AU7/12AX7 dual triodes that are still in demand today in high end audio equipment. In fact these military tubes were pin for pin identical and would work perfectly in those civilian audio applications.
*AC&W - Aircraft Control and Warning