Downloaded from https://www.everyspec.com MIL-STD-1311D METHOD 1202 FILAMENT BURNOUT 1. Purpose. The purpose of this test is to ensure that the filament suspension is designed such that when the filament opens, no permanent short circuit occurs between the filament and any element carrying anode voltage. 2. Procedure. Raise the Ef until the filament opens. Test for shorts from the filament to elements carrying B+ voltage. 3. Acceptance criteria. If a short circuit is indicated and passes a current in excess of five times the rated filament current without burning out the short circuit, the tube will be deemed a failure. NOTE:
This test is normally carried out during qualification approval testing only. 4. This is a destructive test. METHOD 1202 1202-1 19 April 1968