Downloaded from https://www.everyspec.com MIL-STD-1311C 31 January 2001 4. GENERAL REQUIREMENTS 4.1 Numbering system. The test methods are designated by numbers assigned in accordance with the following system. 4.1.1 Category of tests. Each test method is designated by a four-digit number, with significance, assigned in accordance with the following criteria: a.
Category of tubes Numerical series (first digit) General (tests applicable to more than one tube category) ..................................1000 to 1999 Receiving, transmitting, and power ......................................................................2000 to 2999 Cold cathode, corona and glow discharge voltage regulators, graphic indicator, ignitron pulse modulators, and thyratrons...............................3000 to 3999 Crossed field, gas switching, klystrons, magnetrons, M-backward wave, O-type backward wave, and traveling-wave tubes....................................4000 to 4999 Cathode ray, cathode-ray charge storage, phototubes, image orthicons, and vidicons.......................................................................................................5000 to 5999 Radiation counter.................................................................................................6000 to 6999 b.
Within the above series, numbers will be assigned as follows: Category of tests Last three digits of series Environmental/Mechanical (physical)...................................................................001 to 199 Electrical..............................................................................................................200 to 499 Life ...................................................................................................................500 to 699 4.1.2 Revisions. Revisions to test methods will be indicated by a capital letter following the method number. For example, the first revision of method 1001 will be 1001A. Letters I and O will not be used.
4.2 Methods of reference. Applicable test methods contained herein shall be referenced on the TSS by specifying the method number of this standard and details required by the test method. Applicable methods shall be referenced without specifying a revision letter. Paragraph numbers within test methods shall not be referenced. If a particular paragraph(s) is applicable, the title shall be specified. 4.3 Order of precedence. Unless otherwise specified, in the event of conflict between this standard and the tube specification sheet (TSS), the latter shall govern (see MIL-PRF-1, paragraphs 2.4, 3.1.1 and A.2.4, Order of precedence.) 4.3.1 Quantity measurement.
When it is stated in any test method that a quantity is to be measured, it is implied that the measurement, after application of any necessary correction factors or calculations, is to be within the limits specified on the TSS, or herein. Consequently, the words ". . . and shall be within the limits specified . . ." are frequently implied but not stated, to avoid constant repetition. 4.3.2 Parameter values. Where any specific value or limit for a parameter is stated herein, the TSS may specify a different value, for good reasons; such value will automatically govern, in accordance with MIL-PRF-1 order of precedence provisions. Consequently the words ". . . or the specified value . .
." are frequently implied but not stated, to avoid constant repetition. In the interests of standardization, TSS's should not adopt different values of such parameters without good reason. 4.4 Obsolescent test methods. Test methods labeled "OBSOLESCENT" are retained in this standard because they are specified on TSS's for a limited number of older tubes. Obsolescent methods shall not be specified on new TSS. If a similar measurement is required for new tube types, a new test method will be prepared under a different number, reflecting current practice. Obsolescent methods will be deleted from this standard when no further requirements exist. 4.5 Destructive tests.
Tubes subjected to a destructive test (see MIL-PRF-1, para. 4.1) shall not be delivered on the contract or order. The manufacturer has the option of using different or the same sample tubes when more than one destructive test is required. Tubes subjected to deteriorating tests, such as environmental, physical, or life tests, which have electrical tests specified as end-point limits, shall conform to the initial limits for those electrical tests, prior to being subjected to deteriorating tests. 4.6 Alternate test methods.
An alternate test method may be substituted for a method specified herein provided it is demonstrated to the qualifying Government activity that there is adequate correlation between the results of the manufacturer's test method and the test method specified herein, and provided that such substitution in no manner relaxes the requirements of MIL- PRF-1 and of this standard. The schematic diagrams and description of the test equipment to be used, shall be made available for review by the qualifying activity (DSCC-VQE, Defense Supply Center Columbus, P.O. Box 3990, Columbus, OH 43216-5000). 5