Special Exhibit:

Prototype TEMCO

(Click on any of the images on this page to see a larger version)

This was the first TEMCO Electronic Control Box, the prototype. It was made by TEMCO’s founder Herb Tomoser sometime around 1955-57. This controller, together with TEMCO’s 5SC servo, enabled standard single channel, single button systems to produce multi control. The production model had a fifth button to activate a separate escapement for throttle control.

Here’s how the production system looked when it was introduced nationally in 1958 (April 58 MAN):

This control box generated one to four pulses, (one to five on production models) depending on which button was pushed. This enabled multi control with greater convenience, reliability and accuracy than the single button alternative. Without the control box, the pilot would have to remember the correct number of pulses and then key them in successfully, not too fast or slow, all under the pressures of varying flight conditions.

But this box was not merely a better way to operate TEMCO’s 5SC servo, it was the
only way. The servos in the initial years were sold only with the controllers, and buyers were warned they would not work otherwise and could not be manually pulsed. We do not yet know why this was true or what modifications were made in the manually operated TEMCO servos, which appeared at the end of 1959.

Sometime between 1959 and 1961 TEMCO introduced a new control box which made automatic keying even easier than the old TEMCO controller. The new control box used a joystick instead of buttons for left-right and up-down controls. Thus, it could be flown more like a real plane with no need to remember which button was which.

This was TEMCO’s prototype of the new joystick control box:

Here is an inside view showing the simple technique employed to replace button controls with stick operation. The buttons were not actually eliminated. They were merely moved inside the box and positioned so they could be pressed by the lower end of the joystick when the tip was moved. The resulting control movements continued to be all-or-nothing, not proportional:

For more information on TEMCO and Herb Tomoser, see TEMCO ONE.