Tektronic Type 106 Square-Wave Generator used for ground support. The generator measures 9 x 6 x 14, with a “Lockheed NAS 10-10900,” label affixed to the top of the housing, and two NASA calibration and certification labels affixed to the front. Another label affixed to the back states that this particular generator has been modified. In fine condition. This generator could be used in such applications as diode recovery, core testing, and digital and analog design. RR Auction COA.