Downloaded from https://www.everyspec.com MIL-STD-1311D METHOD 1116 (Subminiature tube) 1. Purpose. This test is conducted in order to detect defects in the tube leads. 2. Procedure. Two leads per tube shall be tested. The leads shall be selected in a cyclical manner (regular recurring), for example, leads No. 1 and 2 on the first tube, leads No. 2 and 3 on the second tube, etc. The lead-fatigue test shall be made by subjecting each lead under test to a pull of 16 ± 1 ounces. Each lead shall withstand four 90 degree arcs of the glass header. An arc is defined as the movement of the lead away from the tube through 90 degrees from normal and back, to normal.
All arcs on a single lead shall be made in the same direction and in the same plane. A lead shall be considered to have failed at the time it breaks off from the tube. 3. Acceptance criteria. Upon completion of the test, acceptance or rejection of the lot shall be based on the number of tubes defective. A tube having one or more defective leads shall be considered a defective tube. NOTE: This is a destructive test; electrical rejects may be used for this test. LEAD FATIGUE METHOD 1116 1116-1 19 April 1968