1、_ _- MIL-R-2367 58 7797706 0372707 O = o TL b-“-a3- 17 MIL -R-82369 (TD) 21 January 1968 NAVAL TRAINING DEVICE CENTER ORLANDO, FLORIDA MILITARY SPEC1 FICATION RECORDER-REPRODUCER, STEREO SOUND (MAGNETIC TAPE TYPE) This speciTication has been approved by the Naval Training Device Center, Department o
2、f the Navy. 1. SCOPE 1.1 Scope.- This specification covers A.C. powered, two speed stereo sound recorder-reproducers, uti lizing the magnetic tape recording method, (see 6.1). 1.1.1 This item has been designated-by the Naval Training Device Center as Device 4A12B, for Navy procurement (see 6.2). 2.
3、APPLICABLE DOCUMENTS 2:.1 The following documents of the issue in effect on the date of i.nvitation for bids or request for proposal, forin a part of this specifi- cation to ,the extent specified herein. . SPECIFICATIONS Fede r a 1 J-C-175 W-M-340 W-R-175 W - T -0 O 70 Cable Assembly, Power, Electri
4、cal, (3-wi re, 3-prong, Groundi ng P1 ug Connector for 125 volt Equipnient) Mi crophone, Dynamic Reel and Hub for lilagnetic Recording Tape, General Specification for Tapes , Recordi ng , Sound and Ins trunienta- tion, Nagnetic Oxide Coated, General Specification for Provided by IHSNot for ResaleNo
5、reproduction or networking permitted without license from IHS-,-,-MIL-R-B2367 58 = 7999706 OL727LO 7 = F MIL-R-82369( TD) PPP-B-585 . Box, Wood, Wi rebound PPP-B-591 PPP-B-601 PPP-B-621 PPP-B -636 PPP -B - 640 Mil i tary MIL-P-116 STAN DARDS Federal FED-STD-102 Mi 1 i tary MIL-STD-105 MI L-STD- 129
6、MIL-STD-461 BOX, Fiberbound, Wood-cleated BOX, Wood, Cleated-plywood BOX, Wood, Nailed and Lock-cornered Box, Fi berboard Box, Fi berboard, Corregated, Tri pl e- wal l Preservation, Methods of, Preservation, Packaging and . Packing Levels Sampling Procedures an Tables for Inspection by Attributes Ma
7、rking for Shipment and Storage El ec t romagne t i c I n t e rf ere nce Character- istics Requirements for Equipment (Copies of specifications, standards, drawings, and publications required by suppliers in connection with specific procurement functions should be obtained from the procuring activity
8、 or as directed by the Contracting ffi Cer. ) 2.2 Other publications.- The following documents form 207 East Ohio Street, Chicago, Illinois 60611; or 1655 Scott Blvd., Santa Clara, California 95050) (Technical society and technical association specifications and standards are generally available for
9、 reference from libraries. distributed among technical groups and using Federal agencies .) They are also 3. REQUIREMENTS 3.1 Materials.- The materials used in sound recorder-reproducer shall be as spec the construction of the stereo fled herein. Materials not tion 3 Provided by IHSNot for ResaleNo
10、reproduction or networking permitted without license from IHS-,-,-MIL-R-2369 58 W 7779706 0172712 O MI L - R- 82 369 ( TD specifically described herein shall be of the best comercial quality, of the lightest practicable weight-and suitable for the purpose intended. 3.1.1 . Characteristics .- 3.1.1.1
11、 Metals.- Metals used shall be either corrosion-resistant or shall be suitably treated to resist corrosion in envi ronmental conditions to which the stereo sound recorder-reproducer will be subjected when in storage or during operation (see 3.2.1.37.1). 3.1.1.2 Plastics.- Plastics shall be durable a
12、nd resistant to cracking, brittleness a discoloration 9 deformation and simi lar defects upon aging or when subjected to hot or cold thermal extremes within the temperature ringe specified for the use of stereo sound recorder- reproducer (see 3.2.1.37.1). 3.2 General design.- The stereo sound record
13、er-reproducer -shall be complete with all necessary devices and controls for automatic operation requiring only connection to the power source of 3.2.1.35. All major and minor assemblies, including accessories, shall be of current standard solid-state design. Facilities shall be provided for recordi
14、ng and playback of audio signals. be capable of four-track monophonic and four-track stereophonic recording and playback. The recorder shall 3.2.1 Des i gn ch aracteri s t i cs. - 3.2.1.1 Amplifier output.- The stereo sound recorder-re roducer power amplifiers shall have a minimum rating of 5 watts
15、(mis P when measured as specified in 4.4.12. . 3.2.1.2 Recording and reproducing medium.- The stereo sound recorder-reproducer shall be capable of using as the recording and reproducing medium, 1/4 inch magnetically coated tape in accordance with the applicable requi rements of W-T-0070. 3.2.1.3 Ree
16、ls.- Reels supplied as part of this recorder-reproducer shall be in accordance with the applicable requirements of W-R-175. The equipment shall be capable of handling up to and including a seven inch reel. stereo sound recorder-reproducer. One empty seven tnch reel shall be supplied with each 3.2.1.
17、4 Tape speeds .- The stereo sound recorer-reproducer shall have the minimum capability of recording and reproducing using tape speeds of 7 1/2 and 3 3/4 inches per second. Tape recorder speed shall meet the applicable portions of the NAB Standard on Magnetic Tape- Recording and Reproducing (Reel to
18、Reel) a April 1965. of the actual speed of the recording/reproducing mechanism shall be performed in accordance with 4.4.3. The measurement 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-82369 C = 9979906 0172713 2 W MIL-R-82369 (TD) 3;2.1;4
19、.3-Tape- speed accuracy.- The tape-speed accuracy shall be - + 5.0% at all speeds. The tolerance on tape speed shall apply to any portion of the reel of tape in use. 3.2.1.5 Interchangeability of components.- Components shall be interchangeable between all stereo sound recorder-reproducers of the sa
20、me type and style manufactured in accordance with this specification. 3.2.1.6 Frequency response.- 3.2.1.6.1 Recordlplayback response.- The stereo sound recorder- reproducer frequency response (record or reproduce) when referred to the appropriate test tape (7 1/2 IPS - Ampex 31321-04 or equal, 3 3/
21、4 IPS - Ampex 31331-01 or equal) shall be as follows, when tested as spec- ified in 4.4.6. Response measurements shall be taken at the preamplifier output of each of the two channels of -the sfr sound recorder-reproducer. Tape speed Response 7 1/2 inches per second (IPS) 3 3/4 inches per second (IPS
22、) 50-15,000 HZ + 3 db 25-50 HZ - 5 db 50-7;500 HZ + 3 db 25-50 HZ - 6-db The complete playback response of the stereo sound recorder-reproducer including preamplifier, power amplifier and loudspeaker system shall be as specified in 3.2.1.29. . 3.2.1.7 Distortion.- The overall preamplifier record-rep
23、roduce total harnionic distortion, including tape, shall be less than 3% rms for a 400 Hertz sine wave signal recorded to achieve a reproduce level 6 db above the standard reference level on the test tape (Ampex 31321-04 or equal). The power amplifier at rated power, shall not exceed three percent t
24、otal harmonic distortion at any frequency from 50 Hz to 15 kHz. 3.2.1.8 Equalization.- Equalization shall conform to the National Association of Broadcasters (NAB) standard equalization curve at each speed. noise signal-to-noise ratio shall not be less than 45 db for either the 7 1/2 or 3 3/4 inches
25、 per second speed. 3.2.1.9 Signal-to-noise.ratio.- The peak record level ta. unweighted 3.2.1.10 Flutter and wow.- Flutter and wow shall not exceed the follow- ing limits when reproducing a 3 kHz test tone from a standard flutter tape (Ampex 01-31326-01 or equal). unweighted RMS percentage when the
26、flutter tape is reproduced: Flutter and wow shall be measured as .an 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-823b7 58 W 7777906 0372734 4 W MIL-R-82369 (TD) Tape - speed F1 utter and NOW (RMS) 7 1/2 inches per second .2% .25% 3 3/4 in
27、ches per second 3.2.1 .ll . Crosstalk.- For four track moiiupnonic or stereophuiiic systems, the adjacent track signal-to-crosstalk ratio shall not be less than 55 db in the range from 100 Hz to 10 kHz. For these measurements, bias shall not be applied to the unrecorded tracks. 3.2.1.12 Fast forward
28、 and rewind.- The stereo sound recorder-reproducer shall be capable of completely winding and rewinding at a speed of at least 10 ft/sec. Maximum speed of the tape transport shall not result in a detectable deterioration of the tape, nor shall 1000 such operations result in a detectable deterioratio
29、n of the equipment. stereophonic systems shall be not less than 40 db between the frequencies of 100 Hz and 10 kHz. be applied to both tracks. 3.2.1.13 Stereophonic channel separation.- The channel separation of For measurements of stereophonic systems, bias shall 3.2.1.14 Accelerated life.- The ste
30、reo sound recorder-reproducer shall meet all the requirements of this specification after 500 hours of continu- ous operati on. 3.2.1.15 Erasure.- Erasure of the tape shall be provided by an AC less than 80 kHz. . frequency erase method. The frequency of the erase oscillator shall be not 3.2.1.16 Ta
31、pe Counter.- A three digit counter shall be provided on the transport of the recorder to indicate length of tape used. 3.2.1.17 Tape-motion controls.- All controls essential to the operation of the tape transport shall be located on the same panel and area of the stero sound recorder-reproducer. in
32、3.2.1.17.1 through 3.2.1.17.6. up to the selected speed from the stop position, in not. more than 1/2 second. recorder-reproducer in the record mode. perform a double function (activating both the play and record switches) to place the recorder-reproducer in this mode, so as to prevent accidental re
33、cord operati on. These shall include the controls specified 3.2.1.17.1 Play switch.- A switch shall be provided to bring the tape 3.2.1.17.2 Record-switch.- A switch shall be prwided to place the However, it shall be necessary to . . -. 0 Provided by IHSNot for ResaleNo reproduction or networking pe
34、rmitted without license from IHS-,-,- MIL-R-82369 58 7777906 0372735 b = MIL-R-82369 (TD) 3.2.1.17.3 Stop switch.- A switch shall be provided to bring the tape to a positive stop from its operating mode within 1/2 second without turning off the power to the electronics .assembly. stereo sound record
35、er-reproducer into the rewind operating mode from any other mode. 3.2.1.17.5 Fast-forward switch.- A switch shall be provided to place the stereo sound recorder-reproducer into the fast-forward operating mode from any other mode. 3.2.1.17.4 Rewind switch.- A switch shall be provided to place the 3.2
36、.1.17.6 Tape-speed-change control .- Capstan speeds shall be selectable by a suitable switch so as to provide any one of the tape speeds of 3.2.1.4. circuit for each speed shall be made automatically when a speed change is made, unless a separate switch is provided for this purpose. In addition, sel
37、ection of the proper equalization 3.2.1 .la Record-level control .- A rotary-type control shall be provided to allow level control on each channel in the record mode. 3.2.1.19 Playback-level control .- A rotary-type control shall be provided to allow control of the preamplifier level on each channel
38、 while in the playback mode. 3.2.1.20 Power switch.- A power switch shall be provided which will 3.2.1.21 Recording indicator.- Indication, that the stereo sound - recorder-reproducer is recording shall be provided by a light or some other disconnect the power supply line when in the “OFF“ position.
39、 visible means (dial marking) 3.2.1.22 Record-level indicator.- A record level indicator shall be provided to indicate the recording level for each channel. shall consist of volume unit (V.U.) meters calibrated so that a zero V.U. reading shall be at 6 db below peak recording level. shall be plainly
40、 visible while operating the stereo sound recorder-reproducer. These indicating meters shall meet the applicable requirements of USAS C 16.5-1954. Peak recording level is defined as that level at which three percent total harmonic distortion of a 400 Hz signal occurs. 3.2.1.23 Channel-selector switc
41、h.- A switch shall be provided on the stereo sound recorder-reproducer to select the desired channel (s) for recording and reproducing. These indicators These indicating meters 3.2.1.24 Safety switch.- A switch shall be provided which will-auto- matically stop the tape transport in case of tape brea
42、kage or end of tape on the reel. 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-823 69 (TD) 3.2.1.25 Monitor switching capability.- A monitor switch(s) shall be provided to select the proper mode for monitoring. monitor the input signal to t
43、he recorder or the recorded signal from the tape. It shall be possible to 3.2.1.26 Power cord.- An eight foot cord, for use with a three-wire system with one of the wires a common ground, shall be provided. When the power source specified is 115-125 volt the cord shall be Type I, series SJ, conformi
44、ng to J-C-175, except that the color of the cord shall be optional. 3.2.1.27 Fuses and fuseho1ders.- All fuses necessary for adequate protection of the recorder-reproducer shall be conveniently mounted so that they may be easily replaced, with Underwriters Laboratories, UL 813. Fuses and fuseholders
45、 shall be in accordance 3.2.1.28 Micronhone.- Two dynamic, noise canceling microphones with omnidirectionalu, ucteristics, which are electronically compatible with the basic recorder, shall be prcvided. applicable requirements of W-M-340. for hand use or for use with desk stands. with each microphon
46、. The microphones shall meet the 3.2.1.28.1 Microphone support.- The microphones shall be designed . A desk stand shall be supplied 3.2.1.29 Loudspeakers.- A 4 to 16 ohm permanent magnet type loudspeaker shall be provided for each of the two stereo channels. shall be mounted in a suitable enclosure
47、to provide a frequency response of plus or minus seven decibels relative to a 1 kHz signal between the limits of 106 and 7500 Hertz, and an output level of at least 90 db when tested as specified in 4.4.11. The loudspeaker 3.2.1.30 Modes of operation.- The stereo sound recorder-reproducer shall be c
48、apable of the following functions: (a (b) (cl (4 3.2.1.31 quarter track in 3.2.1.30. Siniul taneous recording on both channels Simultaneous playback from both channel s Monitoring (See 3.2.1.25) Selectable speeds of 3 3/4 inches per second (IPS) and 7 1/2 IPS. Head assembly.- Erase and record/playba
49、ck heads shall be of stereo configuration in order to provide the functions listed Erase heads shall be oriented in such a manner that the tape is erased prior to reaching therecording head. core design. Heads shall be of laminated 8 - f- Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-82369 58 9999906 0372737 T , MIL-R-82369( TD) 3.2.1.31.1 Three head a
