1、MIL-F-2BLLA 66 9779706 OL36366 3 f -d7-43- s i.2 MIL-S-901 MIL-P-15024 MIL-E-15090 MIL -E -16400 MIL-E-17555 MIL-C-39012/25 STANDARDS Shock Test, H.I. (High-Impact); Shipboard Machinery, Equipment And Systems, Requirements For Plate, Tags And Bands For Identification Of Equipment Enamel, Equipment,
2、Light-Gray (Formula No. 111) Electronic Interior Cbmmunication And Navigation Equipment, Naval Ship And Shore: Electronic And Electrical Equipment, Accessories, And Repair Parts; Packaging And Packing Of Connector, Coaxial, Radio Frequency (Hardware For Radio Frequency Coaxial Connectors) General Sp
3、ecification For MIL-F-28811A( EC) 26 April 1985 SUPERSEDING MIL-F-28811(EC) 17 March 1975 MILITARY SPECIFICATION FREQUENCY STANDARD, CESIUM BEAM TUBE This specification is approved for use by the Space and Naval Warfare Systems Command, Department of the Navy, and is available for use by all Departm
4、ents and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers the performance requirements for a time and frequency standard, hereinafter referred to as the instrument, which uses a cesium beam tube resonator to stabilize the output frequency of a quartz crystal oscil
5、lator. The instrument provides an extremely high order of frequency accuracy and is capable of serving as a primary frequency reference. 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.1 Specifications and standards, Unless otherwise specified, the following specifica- tions and standards of t
6、he issue listed in that issue of the Department of Defense Index of Specifications and Standards (DoDISS) specified in the solicitation form a part of th.is specifica- tion to the extent specified herein. . SPECIFICATIONS MILITARY MILITARY MIL -STD-12 MIL-STD-105 MIL-STD-109 MIL-STD-167-1 MIL-STD-18
7、8 MIL-STD-415 MIL-STD-461 MIL-STD-462 MIL-STD-471 Abbreviations For Use On Drawings, Specifications, Standards And In Technical Documents Sampling Procedures And Tables For Inspection By Attributes Quality Assurance Terms And Definitions Mechanical Vibrations Of Shipboard Equipment (Type I - Environ
8、- mental And Type II - Internally Excited) Military Communication System Technical Standards Test Provisions For Electronic Systems And Associated Equipment, Design Criteria For Electromagnetic Emission And Susceptibility Requirements For The Control Of Electromagnetic Interference Electromagnetic I
9、nterference Characteristics, Measurement Of Maintainabi 1 ity Verif icat ion/Demonstration/Evaluat ion I I Beneficial coments (recommendat ions, additions, deletions) and my pertinent data which may be of use in improving this document should be addressed to: Warfare Systems Command (SPAWAR-8111), W
10、ashington, DC 20363-5100, by using the self- addressed Standardization Document Improvement Proposal (DD Fom 1426) appearing at the end of this document, or by letter. Commander, Space and Naval THIS DOCUMENT CONTAINS 35 _ PAGES % FSC 6625 Licensed by Information Handling ServicesProvided by IHSNot
11、for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-F-28833A bb 19999906 0336367 5 i- MIL -STD -781 MIL-STD-810 MIL-STD-965 DoD-STD-1399, MIL-STD-1472 MIL-STD-1631 MS-3102 MS-3 122 MS-3476 MS-25043 Section 300 MIL-F-28811A( EC) Reliability Design Qualification And Pro
12、duction Acceptance Tests: Exponential Distribution Environmental Test Methods And Engineering Guidelines Parts Control Program Interface Standard For Shipboard Systems, Electric Power, Alternating Current (Metric) Human Engineering Design Crlter-ia For Military Systems, Equip- ment And Facilities Pr
13、ocedure For Selection Of Electronic And Electrical Parts And Materials During Design Of Military Items Connector, Receptacle, Electric, Box Mounting Connector, Receptacle, Electric, Series 1, Crimp-Type, Box Mounting, Flange, No. 4 Holes Connector, Plug, Electric, Series 2, Crimp-Type, Bayonet Coupl
14、ing, Classes A, L, S, And W Cover, Electrical Connector, Receptacle, AN Type 2.1.2 Other Government publications. The fol lowing other Government pub1 icat ions form a part PUBLICATIONS of this specification to the extent specified herein. NAVAL AIR SYSTEMS COMMAND (NAVAIR) WS-6536 Process Specifica
15、tion Procedures And Requirements For Prepara- tion And Soldering Of Electrical Connections NAVAL MATERIAL COMMAND (NAVMAT) NAVMAT P4855-1 Navy Power Supply Reliabiltty, Design And Manufacturing Guide- 1 ines (Copies of specifications, standards, and publications required by manufacturers in connec-
16、tion with specific procurement functions should be obtained from the procuring activity or as directed by the contracting officer.) 2.2 Other publication(s). extent specified herein. The issue of the document which is indicated as DoD adopted shall be the issue listed in the current DoDISS and the s
17、upplement thereto, if applicable. The following document forms a part of this specification to the ELECTRONIC INDUSTRIES ASSOCIATION (EIA) EIA RS-310-C-77 Racks, Panels, And Associated Equipment (Application for copies should be addressed to Electronic Industries Association, (Industry association s
18、pecifications and standards are generally available for reference from 2.3 Order of precedence. 3. REQUIREMENTS 3.1 General. specified .- 3.1.1 First article. When specified, a sample shall be subjected to first article inspec- tion (see 4.3 and 6.3). 3.2 Description. The instrument shall contain a
19、quartz crystal oscillator, a means of synthesizing a microwave frequency near the hyperfine transition frequency of cesium 133 (9,192,631,770 hertz (Hz) from the quartz oscillator frequency, and a means of comparing the synthesized microwave frequency with the hyperfine transition frequency. compari
20、son shall be used to correct the frequency of the crystal oscillator to reduce to a minimum the difference between the synthesized microwave frequency and the hyperfine trans it ion frequency. Means shall be provided to operate the crystal oscillator at a frequency referenced to atomic time. 2001 Ey
21、e Street, NW, Washington, DC 20006.) libraries. and the references cited herein, the text of this specification shall take precedence. They are also distributed among technical groups and using Federal agencies.) In the event of a conflict between the text of this specification The instrument shall
22、be in accordance with MIL-E-16400, except as hereinafter The result of the i I e: 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-_- . ._ MIL-F-ZLLA 66 W 7777906 OL3636 7 W MIL-F-28811A( EC) 3.3 Construction. The instrument shall consist of the ite
23、ms specified in a through i and other parts specified herein as required to make up a complete instrument: a. b. d. e. f. 9. h. i. C. Ces i um beam tube Power supply Standby power supply (internal battery optional) Quartz crystal oscillator Dividers Warning indicators for improper operation Synthes
24、i Zer Clock Access or i es 3.4 Performance. 3.4.1 Warmup. 3.4.2 Accuracy. The instrument, without reference to or calibration with an external standard, shall be capable of producing a frequency that is within f3 x of that used for the International Definition of the Second (as referenced against th
25、e disseminated time scale of the U.S. Naval Observatory (USNO). -28C to +65C and magnetic flux densities as specified in 3.8.3.1, or any combination thereof. frequency within fl x 10-l after having been turned off or having any one of its electronic modules (exclusive of beam tube) repaired or repla
26、ced and properly aligned and the instrument replaced in the same environment. Performance shall be as specified in 3.4.1 through 3.4.13. The instrument shall be fully operable and shall conform to all the require- ments of thi-ification within 20 minutes from -28 Celsius IC) ambient temperature. Thi
27、s accuracy shall be maintained during temperature exposure from 3.4.3 Reproducibility. The instrument shall be capable of returning to the previous 3.4.4 Settability. The instrument shall be capable of being calibrated to within I(2) x flux densities as specified in 3.8.3.1, and any combination ther
28、eof. calibration adjustment shall be at least 6.0 parts per (pp) 10 of the USNO time scale during temperature exposure from -28C to +65“C and magnetic The total range of the . 11 . The instrument shall display no systematic drift and shall not 3.4.5 Long-term stability. change from the original freq
29、uency more than I1 x for the life of the cesium beam tube. Frequency measurements made at different times shall be made in the same environment with the tolerances specified in a through c: a. Temperature: f5C b. Magnetic field: f0.2 gauss c. Humidity: I10 percent relative humidity 3.4.6 Short-term
30、stability. The standard deviation of the short-term instabilities shall not exceed the limits speci-fied in a through c: a. b. 5 7 x for 1 second sample intervals c. 5 8 x lo- for 100 microsecond (ps) sample intervals 5 7 XX- for sample intervals greater than 1 second and less than 1 day T 3.4.7 Sin
31、usoidal outputs. The instrument shall provide isolated sinusoidal outputs at both the front and rear panels as specified in TABLE I. TABLE I. Sinusoidal outputs. I Frequency 1 Front I Rear 5 MHz - 4 1 1 1 MHz 1 160 kHz 1 1 - l/ Megahertz - 21 Kilohertz The isolation between any sinusoidal output and
32、 any other sinusoidal output specified shall be a minimum of 40 decibels (dB) in the frequency range of 10 kHz to 10 MHz. test signal used to verify the isolation shall be not greater than O dB nor less than -10 dB relative to the rated level of the sinusoidal output under test. The amplitude of the
33、 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-ZLLA bb = 777770b 033b3b7 7 MIL-F-28811A( EC) 3.4.7.1 Amplitude. Pmplitude shall be not less than 1 than 1.5 Vrms into 50 ohms. 3.4.7.2 Harmonic distortion. Harmonic distortion shal volt root-m
34、ean-square (Vrms) nor more be 40 dB below rated output. 3.4.7.3 Nonharmonic output. At least 80 dB below rated output except under the extremes of vibration or magnetic field environments specified in 3.8, in which case the non-harmonic output shall be at least 60 dB below rated output. 5-MHz and 1-
35、MHz outputs, but excluding a bandwidth of fl Hz from the output frequency, shall be at least 80 dB below the output level except under the extremes OP vibration or magnetic field environments specified in 3,8,3, in which case the phase noise shall be at least 60 dB below the rated output. 3.4.7.5 Sh
36、ort circuit protection. All outputs shall be protected from damage due to short circuits at any of the terminals. There shall be no degradation below the specified performance 1.imits of any sinusoidal output by short circuit of any other sinusoidal output or combinations of outputs. 3.4,7.4 Signal-
37、to-noise ratio (SNR). The phase noise in a 30-kHz bandwidth centered at the 3.4.8 Timing pulse and direct current (DC) outputs. The instrument shall include a digital divider and clock that will provide the specified isolated timinq pulse outputs at the front and - rear panels: Pulse repetition freq
38、uency (prf) Front Rear 1 pulse per second (pps) 1 1 1 pulse per minute (ppm) 4 In addition, a minimum of 40 dB isolation shall be provided between any of the 1 ppm outputs in the frequency range of 10 kHz to 10 MHz. be 2.2 Vrms. low value shall be O V, f0.5 V, from ground reference into 50 ohms. For
39、 test purposes, the maximum interfering signal shall 3.4.8.1 Amplitude. The pulse output shall have a high vahe of 10 volts (V), fl V, and the 3.4.8.2 Width. The width shall be 20 ps, +50 percent, -20 percent, into a 60-ohm load. 3.4.8.3 Rise time. The rise time from the 10 percent to the 90 percent
40、 value of pulse 3.4.8.4 Fall time. The pulse fall time from the 90 percent to the 10 percent value of 3.4.8.5 Jitter. The phase jitter on the leading edge of the pulse outputs shall be less 3.4.8.6 Noise immunity. The timing of the output pulses and the circufts that generate the amplitude shall be
41、not greater than 50 nanosecands (ns). pulse amp1 itude shall be not greater than 1 ps. than 5 ns rootwsquare (rms) referenced to the 5-MHZ output averaged over 10,000 pulses. output pulses shall not be harmed or degraded below specified performance by application of external pulses 1 ps wide up to 2
42、00 V peak from a 50-ohm source. damage due to short circuits at any of the terminals. specified performance limits of any pulse output by short circuit of any other pulse output. be less than 5 ns referenced to the 5-MHz output. 3.4.8.7 Short-circuitgrotection. The outputs specified +n 3.4.8 shall b
43、e protected from There shall be no degradation below the 3,4.8.8 Temperature stability. The phase change of the pulse outputs, per degree Cy shall 3.4.8.9 Pulse advance. The time of the 1 pps and 1 ppm output shall be adjustable from the front panel over a range of 1 second in discrete steps of 100
44、milliseconds (ms) 10 ms, and 1 ms, and 100 ps, 19 ps, 1 ps, and 0.1 ps, 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-F-2BLLA bb W 777770b 0336370 5 W MIL-F -2881 lA( EC) 3.4.8.10 Automatic synchronization. The l-ppm and l-pps output shall sy
45、nchronize auto- matically, with a preset advance (see 3.4.8.9), to the leading edge of an external pulse. synchronization error shall be not greater than 10.5 ps. An external synchronization input jack shall be provided on the front panel. The external synchronization pulse shall have an amplitude o
46、f not less than +5 V rise time of not more than 50 ns from 0.5 V to 5 V and a pulsewidth of not less than 500 ns into 50-ohms nominal impedance. A front panel control shall be provided to initiate synchronization. coincidence with any selected l-pps output pulse of the l-minute period. the next l-pp
47、s pulse after the reset switch is depressed, the time display shall change to the next minute and OO-second, and the l-ppm pulses thereafter occur at each OO-second event and within 100 ns of the corresponding l-pps output pulses. rear panel when any interruption occurs that prevents the instrument
48、from operating as a frequency standard, as specified in a through c: 5.5 VDC The 3.4.8.11 One-ppm reset. The l-ppm output shall be settable from the front panel to With the occurrence of 3.4.8.12 Timing fault output. The instrument shall provide a timing fault output at the a. b. Fault indication -
49、not less than O VDC; not more than 0.5 VDC c. Normal operation - not less than 3 volts direct current (VDC); not more than When loaded with 5000 ohms connected to t5 VDC (standard transistor logic load) 3.4.9 Open loop quartz crystal oscillator performance. Provision shall be made for operating stress compensated (SC)-cut quartz crystal oscil lator independently of the cesium reference. When so operated,.the 5-MHZ output signal of the instrument shall conform to the requirements of 3.4.9
