1、AMSC N/A FSC 5985 MIL-DTL-28791C 10 March 2011 SUPERSEDING MIL-DTL-28791B 10 July 2006 DETAIL SPECIFICATION ISOLATORS AND CIRCULATORS, RADIO FREQUENCY, GENERAL SPECIFICATION FOR This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. T
2、his specification covers the general requirements for isolators and circulators, coaxial, waveguide, and stripline radio frequency for use in armed service radar and radio application. 1.2 Part or identifying number (PIN). Pins to be used for devices acquired to this specification are created as fol
3、lows. The PIN consists of the letter “M” followed by the basic number of the specification sheet, and an assigned dash number (see 3.1). M28791/1 - 001 Military designator and specification sheet number Dash number designated on specification sheet 2. APPLICABLE DOCUMENTS 2.1 General. The documents
4、listed in this section are specified in sections 3 and 4 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, do
5、cument users are cautioned that they must meet all specified requirements documents cited in sections 3 and 4 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a
6、 part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract (see 6.2). COMMERCIAL ITEM DESCRIPTIONS A-A-59588 - Rubber, Silicone. FEDERAL SPECIFICATIONS TT-P-645 - Primer, Paint, Zinc-Molybdate, Alky
7、d Type. INCH-POUND Comments, suggestions, or questions on this document should be addressed to: Commander, DLA Land and Maritime, ATTN: VAT, P.O. Box 3990, Columbus, OH 43218-3990, or e-mailed to TubesAmpsdla.mil. Since contact information can change, you may want to verify the currency of this addr
8、ess information using the ASSIST Online database at https:/assist.daps.dla.mil. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28791C 2 DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-DTL-3922 - Flanges, Waveguide, General Purpose, General Specific
9、ation for. MIL-DTL-14072 - Finishes for Ground Based Electronic Equipment. MIL-DTL-15090 - Enamel, Equipment, Light Gray (Navy Formula No. 111). MIL-PRF-39012 - Connectors, Coaxial, Radio Frequency, General Specification for. MIL-DTL-28791/1 - Isolator, Radio Frequency, Coaxial. FEDERAL STANDARDS FE
10、D-STD-H28 - Screw-Thread Standards for Federal Services. DEPARTMENT OF DEFENSE STANDARDS MIL-STD-129 - Military Marking for Shipment and Storage. MIL-STD-202 - Electronic and Electrical Component Parts. MIL-STD-1285 - Marking of Electrical and Electronic Parts. MIL-STD-2073-1 - Military Packaging, S
11、tandard Practice for. DEPARTMENT OF DEFENSE HANDBOOKS MIL-HDBK-454 - General Guidelines for Electronic Equipment. (Copies of the above documents are available online at https:/assist.daps.dla.mil/quicksearch or from the Standardization Document Order Desk, Building 4D, 700 Robbins Avenue, Philadelph
12、ia, PA 19111-5094.) 2.3 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, issues of these documents are those cited in the solicitation or contract (see 6.2). ASTM INTERNATIONAL (ASTM) ASTM-B210 - Standard Sp
13、ecification for Aluminum and Aluminum-Alloy Drawn Seamless Tubes ASTM-B372 - Standard Specification for Seamless Copper and Copper-Alloy Rectangular waveguide Tube (Copies of the above documents are available online at http:/www.astm.org or can be requested from ASTM International, 100 Barr Harbor D
14、rive, West Conshohocken, Pennsylvania 19428-2959.) INTERNATIONAL ORGANIZATION FOR STANDARDIZATION (ISO) ISO 10012 - Quality Assurance Requirements for Measuring Equipment - Part 1: Metrological Confirmation System for Measuring Equipment (Copies of this document are available from the International
15、Organization for Standardization, American National Standards Institute, 11 West 42ndStreet, 13thFloor, New York, NY 10036 or at http:/www.iso.ch.) NCSL INTERNATIONAL NCSL-Z540.3 - Requirements for the Calibration of Measuring and Test Equipment. (Copies can be obtained online at http:/www.ncsli.org
16、 and are available at NCSL International, 2995 Wilderness Place Suite 107, Boulder, CO 80301-5404.) 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this document and the references cited herein (except for related specificatio
17、n sheets), the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28791C 3 3. RE
18、QUIREMENTS 3.1 Specification sheets. The individual item requirements shall be as specified herein and in accordance with the applicable specification sheet. In the event of any conflict between requirements of this specification and the specification sheet, the latter shall govern. 3.2 First articl
19、e inspection. Products furnished under this specification shall be products which have passed the first article inspection in 4.4. 3.3 Materials. The materials shall be as specified herein; however, when a definite material is not specified, a material shall be used which will enable the isolators a
20、nd the circulators to meet the performance requirements of this specification. Acceptance or approval of any constituent material shall not be construed as a guaranty of the acceptance of the finished product. 3.3.1 Copper alloy. Copper alloy used in the fabrication of waveguide-type isolators and c
21、irculators shall conform to commercial bronze, 90 percent, of ASTM-B372. Copper alloy used in the fabrication of coaxial-type isolators shall conform to the material requirements of ASTM-B372, 99.90 percent purity. 3.3.2 Aluminum alloy. Aluminum alloy shall conform to the requirements for 6061 or 60
22、63 of ASTM-B210. The finished waveguide shall have an “F” temper and after heat treatment and aging, shall meet the mechanical properties of the T6 temper of ASTM-B210. 3.3.3 Rubber. Rubber shall conform to the requirements in A-A-59588. 3.3.4 Pure tin. The use of pure tin, as an underplate or final
23、 finish, is prohibited both internally and externally. Tin content of radio-frequency isolator and circulator components and solder shall not exceed 97 percent, by mass. Tin shall be alloyed with a minimum of 3 percent lead, by mass (see 6.6). 3.4 Design and construction. Isolators and circulators s
24、hall be designed and constructed to conform to the requirements specified (see 3.1), in a manner entirely suitable for their intended use. They shall be of the lightest practicable weight consistent with the strength required for sturdiness, safety, and reliability. Isolators and circulators shall b
25、e fully shielded to external magnetic fields. 3.4.1 Waveguide isolators and circulators. The mating face of the isolators or of the circulators shall be so designed and manufactured as to provide the mating characteristics of the flange specified (see 3.1) in accordance with MIL-DTL-3922. 3.4.2 Coax
26、ial isolators and circulators. Connectors shall be as specified (see 3.1). The material and gauging for receptacle connectors shall conform to the requirements of MIL-PRF-39012. 3.4.3 Dimensions. The dimensions shall be as specified (see 3.1). 3.4.4 External finish. External finish shall be applied
27、to the isolators and to the circulators regardless of plating or chemical treatment, except that the mating surfaces shall not be coated. The primer coat shall be zinc chromate conforming to TT-P-645. Two finish coats of enamel, conforming to type III, class 2, of MIL-DTL-15090, shall be applied. Ex
28、ternal coatings shall be applied as continuous films. 3.4.5 Dissimilar metals. Dissimilar metals between which an electromotive couple may exist shall not be placed in contact with each other. Refer to MIL-DTL-14072 for the definition of dissimilar metals. 3.4.6 Screw threads. Screw threads shall be
29、 in accordance with FED-STD-H28. If used, helical inserts shall be selected (for information refer to MIL-HDBK-454, Guideline 12). 3.4.7 Engineering parameters. The parameters of nominal impedance, voltage rating, frequency range, temperature range, and power rating shall be as specified (see 3.1).
30、Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28791C 4 3.5 Dielectric withstanding voltage (applicable to coaxial circulators only). When circulators are tested as specified in 4.7.2, there shall be no evidence of breakdown. 3.6 Isolation.
31、When isolators and circulators are tested as specified in 4.7.3, the isolation shall be as specified (see 3.1). 3.7 Insertion loss. When isolators and circulators are tested as specified in 4.7.4, the insertion loss shall not exceed the value specified (see 3.1). 3.8 Voltage standing wave ratio (VSW
32、R). When isolators and circulators are tested as specified in 4.7.5, the VSWR shall not exceed the value specified (see 3.1). 3.9 Shock (specified pulse). When isolators and circulators are tested as specified in 4.7.6, there shall be no change in electrical or mechanical performance. 3.10 Thermal s
33、hock. When isolators and circulators are tested as specified in 4.7.7, there shall be no evidence of damage or electrical degradation due to the test. 3.11 Moisture resistance. When isolators and circulators are tested as specified in 4.7.8, there shall be no change in electrical or mechanical perfo
34、rmance or destructive corrosion. Destructive corrosion shall be construed as any type of corrosion which in any way interferes with electrical or mechanical performance. 3.12 Vibration, high frequency. When isolators and circulators are tested as specified in 4.7.9, there shall be no change in elect
35、rical or mechanical performance. 3.13 Marking. Isolators and circulators shall be marked with the military part number, manufacturers code and numbers identifying each port (see 3.1). Marking shall be applied directly on the isolators or on an attached name plate. Marking shall be in accordance with
36、 MIL-STD-1285. 3.14 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent possible provided that the material meets or exceeds the operational and maintenance requirements, and promotes economic
37、ally advantageous life cycle costs. 3.15 Workmanship. Isolators and circulators shall be processed in such a manner as to be uniform in quality and shall be free from defects that affect life, serviceability, or appearance. 4. VALIDATION 4.1 Test equipment and inspection facilities. Test and measuri
38、ng equipment and inspection facilities of sufficient accuracy, quality, and quantity to permit performance of the required inspection shall be established and maintained by the supplier. The establishment and maintenance of a calibration system to control the accuracy of the measuring and test equip
39、ment shall be in accordance with NCSL-Z540.3 or ISO 10012. 4.2 Classification of inspections. The inspections specified herein are classified as follows: (a) Materials inspection (see 4.3). (b) First article inspection (see 4.4). (c) Conformance inspection (see 4.6). 4.3 Materials inspection. Materi
40、als inspection shall consist of certification supported by verifying data that the materials listed in table I used in fabricating the isolator or the circulator are in accordance with the applicable referenced specifications or requirements prior to such fabrication. Provided by IHSNot for ResaleNo
41、 reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28791C 5 TABLE I. Materials inspection. Material Requirement paragraph Applicable specification Copper alloy 3.3.1 ASTM-B372 Aluminum alloy 3.3.2 ASTM-B210 Rubber 3.3.3 A-A-59588 4.4 First article inspection. 4.4.1 Samples. F
42、irst article inspection shall be performed by the supplier, after award of the contract and prior to production, at a location acceptable to the Government. First article inspection shall be performed on sample units that have been produced with equipment and procedures normally used in production.
43、First article approval is valid only on the contract or purchase order under which it is granted unless extended by the Government to other contracts or purchase orders. 4.4.2 Sample size. Two isolators and/or two circulators shall be subjected to the first article inspection. 4.4.3 Inspection routi
44、ne. The first article samples shall be subjected to the inspection specified in table I and table II. TABLE II. First article inspection. Examination or test Requirement paragraph Test method paragraph Visual and mechanical examination Dielectric withstanding voltage 1/ . Isolation. Insertion loss .
45、 VSWR . Shock (specified pulse) . Thermal shock . Moisture resistance . Vibration, high frequency 3.1 thru 3.4, 3.13 and 3.14 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 4.7.1 4.7.2 4.7.3 4.7.4 4.7.5 4.7.6 4.7.7 4.7.8 4.7.9 1/ Coaxial type circulators only. 4.4.4 Failures. One or more failures shall be cause
46、 for refusal to grant first article approval. 4.5 Inspection conditions. Unless otherwise specified herein, all inspections shall be performed in accordance with the test conditions specified in the “GENERAL REQUIREMENTS” of MIL-STD-202. 4.6 Conformance inspection. 4.6.1 Inspection of product for de
47、livery. Inspection of product for delivery shall consist of group A and group B inspections. 4.6.1.1 Inspection lot. An inspection lot shall consist of all isolators or all circulators of one type produced under essentially the same conditions, and offered for inspection at one time. 4.6.1.2 Group A
48、 inspection. Group A inspection shall consist of the examinations and test specified in table III in the order shown. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28791C 6 TABLE III. Group A inspection. Examination or test Requirement para
49、graph Test method paragraph Visual and mechanical examination 3.1 thru 3.4, 3.13 and 3.14 4.7.1 Dielectric withstanding voltage 1/ 3.5 4.7.2 1/ Applicable to coaxial only. 4.6.1.2.1 Group A sampling plan. Statistical sampling and inspection shall be performed on an inspection lot basis with a random sample of isolators or of circulators selected in accordance with table IV. The acceptance levels shall be based u
