1、 INCH-POUND MIL-DTL-55535A 28 February 2007 SUPERSEDING MIL-H-55535(EL) 23 January 1967 DETAIL SPECIFICATION HEADSET-MICROPHONE KIT MK-1039/G This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers Headset-Mic
2、rophone Kit MK-1039/G. This Headset-Microphone Kit is designed to fit both the regular and large size Combat Vehicle Crewmans Helmet. The electrical characteristics of the kit are compatible with Tactical Radio Systems, such as the VRC-12. The impedance of the microphone circuit is 150 ohms, and the
3、 earphone elements are transformer matched and present a 500-ohm load to the earphone circuit. 1.2 Classification. Each MK-1039/G kit is composed of the following components: a. Switch Housing Assembly SA-1552/G (80063 / SM-D-700882) 1 each b. Upper Cord set CX-10453/G (80063 / SM-C-317800) 1 each c
4、. Microphone and Boom Assembly M-138/G (81349 / MIL-PRF-26542/10) 1 each d. Retractile Cord Assembly CX-8650B/G (80063 / SM-D-436079) 1 each e. Earphone Elements H-269/G (80063 / SM-C-436361) 2 each f. Cord set Earphone CX-10454/G (80063 / SM-D-700914) 2 each g. Ear Cushion Right Hand 1 each h. Ear
5、Cushion Left Hand 1 each 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as example
6、s. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, st
7、andards, and handbooks. The following specifications, standards, and handbooks form a part of this do therwise specified, the issues of these documents are thoInactive for new design after February 28, 2007 Comments, suggestions, Center, Columbus, Attn: VAI, sounddscc.dla.mil. Sinthis address inform
8、ation using AMSC N/A Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHScument to the extent specified herein. Unless ose cited in the solicitation or contract. or questions on this document should be addressed to: Defense Supply P.O. Box 3990, Columbus, Ohi
9、o, 43218-3990 or emailed to ce contact information can change, you may want to verify the currency of the ASSIST Online database at http:/assist.daps.dla.mil. FSC 5965-,-,-MIL-DTL-55535A 2DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-C-3885 - Cable Assemblies and Cord Assemblies, Electrical for use in El
10、ectronic Communication and Associated Electrical Equipment. MIL-C-10392 - Cable, Special Purpose, Electrical (Miniature). MIL-F-14072 - Finishes for Ground Based Electronic Equipment. DEPARTMENT OF DEFENSE STANDARDS MIL-STD-202 - Test Methods for Electronic and Electrical Component Parts. MIL-STD-25
11、2 - Wired Equipment, Classification of Visual and Mechanical Defects. MIL-STD-810 - Environmental Engineering Considerations and Laboratory Tests MIL-STD-13231 - Marking of Electronic Items. (Copies of these documents are available online at http:/assist.daps.dla.mil/quicksearch/ or http:/assist.dap
12、s.dla.mil from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.2.2 Other Government documents, drawings, and publications. The following other Government documents, drawings, and publications form a part of this document to the extent specifi
13、ed herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. DRAWINGS U.S. ARMY SC-D-10598 - Microphone Test Equipment, ARL-174-A, Calibration general. 3.3.1 Magnetized materials. The materials used in the magnetic circuit shall be of such a c
14、haracter and shall be so processed and assembled that the microphone and earphone elements will not suffer objectionable degradation in performance, due to loss in magnetization over long periods of storage or service. 3.3.2 Diaphragm and air gap. The stability of diaphragm material and the concentr
15、icity of the air gap shall not be affected by extended aging and exposure to environmental conditions. There shall be no foreign material present in the air gap. 3.3.3 Pure tin. The use of pure tin, as an underplate or final finish, is prohibited both internally and externally. Tin content of loudsp
16、eaker components and solder shall not exceed 97 percent, by mass. Tin shall be alloyed with a minimum of 3 percent lead, by mass (see 6.8). 3.3.4 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum e
17、xtent possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-55535A 43.4 Finish. Equipment s
18、hall be finished, as specified in MIL-F-14072, type I. 3.5 Marking. Marking shall conform to MIL-STD-13231. 3.5.1 Serial numbers. Serial numbers are not required. 3.6 Microphone. 3.6.1 Microphone response. The frequency response of the microphone shall be essentially flat from 300 to 3,500 Hz. The m
19、inimum power output of the microphone shall be 56 dBm (the term “dBm” is used, when a power of one milliwatt is the reference level) at 1,000 Hz, when measured in accordance with 4.7.1. In addition, the response shall fall within the envelope on figure 1. During this test, the microphone shall be te
20、rminated with a non-inductive load of 150 ohms. 3.6.2 Distortion. Total harmonic distortion shall not exceed 5 percent at a sound pressure level of 115 dB referenced at 20 Pa (micropascal) over the frequency range of 300 to 3,500 Hz (see 4.7.2). 3.6.3 Signal to noise ratio. The signal-to-noise ratio
21、 of the microphone shall be at least 15 dB (signal over noise), when measured in accordance with 4.7.3. 3.6.4 Dielectric strength, and insulation resistance (see 4.7.4). There shall be no evidence of insulation breakdown. There shall be no decrease in insulation resistance below 1 megohm following t
22、his test. 3.7 Earphone. The earphone element shall be constructed in accordance with ECOM Drawing SM-C-436361. 3.7.1 Earphone response (see 4.8.1). The output of the earphone shall be not less than 103 dB above a reference level of 20 Pa, when 1 milliwatt rms power at 1,000 Hz is applied to the earp
23、hone terminals. The response of the earphone at any frequency shall not deviate from the 1,000 Hz response by more than the values shown in table I (see figure 2). TABLE I. Earphone response. Deviation from 1,000 Hz (dB)Frequency (Hz)Min. Max. 300 - 1,0001,000 - 3,500-3.5 -5 +1.5 +5 3.7.2 Distortion
24、. The acoustic output of the earphone shall have no more than 5 percent total harmonic distortion over the audio frequency range of 300 to 3,500 Hz, when measured as specified in 4.8.3. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-55535A 5
25、Frequency points 300 Hz 600 Hz 2,500 Hz3,500 Hz7,000 Hz Upper limits (dB) +4.0 +4.0 +7.0 +7.0 +0.5 Lower limits (dB) -15.0 -4.0 -4.0 - - FIGURE 1. Microphone response limit curves (see 3.6.1). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-5
26、5535A 6NOTES: 1. Minimum sensitivity at 1 KHz: 103 dB minimum. 2. Impedance: 15 Ohms. 3. Sensitivity Reference: 0 dB =20 Pa (micro-Pascal). FIGURE 2. Earphone response limit curves. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-55535A 73.7.
27、3 Overload. The earphone shall show no more than 3 dB change from its original response curve, after being subjected to the test specified in 4.8.4. 3.7.4 Dielectric strength, and insulation resistance. There shall be no evidence of insulation breakdown. There shall be no decrease in insulation resi
28、stance below 1 megohm following the test (see 4.8.5). 3.7.5 Impedance. The impedance of the earphone at 1,000 Hz shall be 15 ohms 20 percent, as determined by the test (see 4.8.2). 3.8 Service conditions. The equipment shall meet the following service conditions. Where a test is referenced, meeting
29、the test shall be considered as compliance with requirement. 3.8.1 Temperature (see 4.13.1). a. Operating: Ambient temperature in the range of + 150 to 40 F (Fahrenheit). (The + 150 F temperature includes affect of sun-load). Exposure at the high temperature extreme not to exceed 4 hours, and at the
30、 low temperature extreme not to exceed 72 hours, at any one time. b. Non-operating: Exposure in the range of + 160 to 80 F; exposure at the high temperature extreme not to exceed 4 hours and at the low temperature extreme not to exceed 24 hours. 3.8.2 Moisture resistance. Equipment shall meet specif
31、ied performance after subjection to the test in 4.13.2. The equipment shall meet the microphone and earphone response requirements of 3.6.1 and 3.7.1 with degradation not to exceed 3 dB. There shall be no evidence of cracking, warping, or other mechanical deterioration. 3.8.3 Altitude (see 4.13.3).
32、The response characteristics of the earphone and microphone shall be measured, and shall not exhibit degradation in performance in excess of 5 dB from the requirements of 3.6.1 and 3.7.1 after being subjected to the following tests. a. Operating: Up to 15,000 feet (16.7 inches of mercury) above sea
33、level. b. Non-operating: Up to 50,000 feet (3.4 inches of mercury) above sea level. 3.8.4 Immersion (see 4.13.4). After completion of an immersion in water at a depth of three feet for 2 hours, any evidence of water in the switch cavity shall be cause for rejection. The microphone and earphone shall
34、 then meet the requirements of 3.6.1 and 3.7.1, respectively. 3.8.5 Salt atmosphere (see 4.13.5). Upon completion of the test, there shall be no evidence of harmful corrosive action or damage due to the salt spray. The earphone and microphone shall not suffer any degradation in response in excess of
35、 3 dB from their initial performance values of 3.6.1 and 3.7.1. 3.8.6 Blast (see 4.13.6). Following the blast test, the earphone and microphone units shall not suffer any degradation in their response of more than 3 dB from the initial performance values of 3.6.1 and 3.7.1. Provided by IHSNot for Re
36、saleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-55535A 83.8.7 Vibration (see 4.13.7). The amplitude of vibration of any part, sub-assembly, or structural member of the equipment shall not exceed twice the amplitude of the vibration applied to the equipment at any fre
37、quency between 10 and 55 Hz. Tests of the earphone element and the microphone element shall be made to determine compliance with 3.6.1 and 3.7.1, respectively, prior to, and after the cycling. Upon completion of the vibration test, the equipment shall exhibit no evidence of loosening of parts or oth
38、er mechanical damage and shall meet full specification requirements. 3.8.8 Bounce. The equipment shall meet specified performance, with no physical damage allowed, after being subjected to the test of 4.13.8. At the conclusion of the test, the equipment shall meet the requirements of 3.6.1 and 3.7.1
39、, with degradation not to exceed 3 dB. 3.8.9 Shock drop. The equipment shall be operable after the test of 4.13.9. Any physical damage shall be minor only. 3.9 Switch life. The switch shall continue to operate properly following 100,000 complete cycles of operation, when tested as specified in 4.12.
40、 3.10 Cord assemblies. Cord assemblies shall be as specified in MIL-C-3885. The earphone cords, CX-10454/G shall be 2 (two) conductor stranded WD-27A/U and shall meet the requirements of MIL-C-10392. The upper cord set, CX-10453/G shall be five-conductor tinsel with one microphone lead shielded. Cor
41、d set CX-8650B/G shall be constructed as specified in drawing SM-D-436079. 3.10.1 Cord dielectric strength and insulation resistance. The end item equipment specified shall be tested (see 4.14). During the test there shall be no evidence of insulation breakdown and at the conclusion of the test, the
42、 insulation resistance shall not have decreased to a value below 1 megohm. 3.11 Operational requirement. Units shall be tested, as indicated in 4.9. The unit under test shall perform in accordance with all requirements of this specification. 3.12 Interchangeability. Like units, assemblies, subassemb
43、lies, and replaceable parts shall be physically and functionally interchangeable without modification of such items or of the equipment (see 4.11). Individual items shall not be hand-picked for fit or performance. Reliance shall not be placed on any unspecified dimension, rating, characteristic, etc
44、. Non-interchangeability of these parts constitutes failure. 3.13 Preconditioning. The equipment shall be capable of meeting the requirements herein, without subsequent processing, after subjection to the bounce preconditioning of 4.6 (also see 4.5). 3.14 Workmanship (see 4.10). The equipments shall
45、 be manufactured and assembled in accordance with the applicable portions of 3.3.1 and 3.3.2: 4. VERIFICATION 4.1 Classification of inspection. The inspection requirements specified herein are classified as follows: a. First article inspection (see 4.3). b. Inspection covered by subsidiary documents
46、 (see 4.4). c. Conformance inspection of equipment (see 4.5). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-55535A 94.2 Inspection conditions. Unless otherwise specified herein, the examinations and the tests specified herein shall be perfo
47、rmed under the following standard test conditions: a. Temperatures between + 59 and + 95 F. b. Normal ground altitude. c. Prevailing room ambient humidity. d. No vibration. 4.3 First article inspection. This inspection shall be performed by the contractor and witnessed by a Government inspector. It
48、shall consist of groups A, B, and C inspections (see table II, table III, and table IV respectively) on 20 samples. The first article samples will be inspected in this order: group A, group B and divided up for group C inspection as follows: 2 units (MK-1039/G) for each of the ten (10) group C tests
49、 listed in table IV. After the completion of group C testing, all acceptable units shall be subjected to and pass all group A inspections. 4.4 Inspection covered by subsidiary documents. The finish (see 3.4) and marking (see 3.5) shall be inspected under the applicable documents, as part of the inspection of equipment before preparation for delivery: 4.5 Conformance
