1、- - y _ EIA 399-A 75 3234600 0067477 I ANSI S4.8 - 1975 Approved June 19, 1975 American National Standards Institute 9. * rn M T Dimensional Standard Coplanar 4. 9 Ly Magnetic Tape Cartrdge Type CP II (Compact Cassette) RS-399-A a JUNE 1975 Engineering Department EL E CT R O %I I C i N DU ST R I ES
2、AS O G I AT i0 N EIA 399-A 75 W 3234b00 O067478 3 W c NOTICE EIA engineering standards are designed to serve the public interest through eliminating mis- understandings between manufacturers and purchasers, facilitating interchangeability and improve- ment of products, and assisting the purchaser in
3、 selecting and obtaining with minimum delay the proper product for his particular need, Existence of such standards shall not in any respect pre- clude any member or nonmember of EIA from manufacturing or selling products not conforming to such standards, nor shall the existence of such standards pr
4、eclude their voluntary use by those other than EIA members whether the standard is to be used either domestically or internationally. Recommended standards are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA
5、 does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the recommended standards. Since EIA RS399 is a dimensional standard only it in itself lacks the complete information as contained in the IEC documents. The additional information wiU b
6、e contained within two future EIA publications. EIA Compact Cassette Standard RS399 is in harmony with IEC publication 94 and 94A with current amendments. Published by ELECTRONIC I NDUSTRI ES ASSOC1ATION Engineering Department 2001 Eye Street, N. W., Washington, D. C. 20006 ,- O Electronic Industrie
7、s Association 1975 All rights reserved Price $2.68 FrinW in U.S.A. - P EIA 399-A 75 m 3234b00 00b7479 5 m RS-399-A Page 1 DIMENSIONAL STANDARD COPLANAR MAGNETIC TAPE CARTRIDGE TYPE CP II (CQMPACT CASSETTE) (From RS-399, formulated under the cognizance ofEIA Working Group P-8.3 on Audio and Digital M
8、agnetic Recording Components and Tape Records. The Compact Cassette Dimensional Standard RS-399 is being reissued as RS-399-A with additions that will serve to clarify the original document. The basic addition is the inclusion of the 45-minute cassette (C-45) to the list of recommended cas- sette le
9、ngths. The second addition is clarification of dimensions appearing on the appended drawings.) 1. SCOPE This standard covers the dimensional specifications considered essential for the successful interchange of cartridge called EIA Type CP-II (Compact Cassette) between equipment designed for audio r
10、ecord- ing and reproducing applications. This standard was prepared because of the lack of an existing industry approved standard on the titled subject. 2. DEFINITION 2.1 Coplanar Magnetic Tape Cartridge designates a design in which the tape is retained within a case. The ends of the tape are secure
11、d to hubs which are located on the same plane. The CP-II is commonly lmown as the Compact Cassette. o 2.2 The Compact Cassette is a twin-hub tape cartridge of the coplanar type; it is suitable for mono/ stereo compatible use. 2.3 Capstan designates a rotating shaft that contacts the tape and serves
12、in conjunction with the pres- sure roller as the tape driving source. 2.4 Pressure Roller designates the rotating member that holds the tape against the capstan in order to obtain a suitable driving action of the tape. 2.5 Magnetic Head designates the transducers that contact the magnetic tape for t
13、he purpose of re- cording, reproducing or erasing a magnetic signal on the tape. 2.6 Internal Tape Supports designate members within the case to maintain the tape within an appro- priate path. 2.7 Fressure Pad designates a resilient member used to hold the tape against a magnetic head. 3. GENERAL SP
14、ECIFICATIONS 3.1 The symmetrical compact cassette has its two sides with provision for being labeled 1 and 2 (or A a EIA 399-A 75 = 3234600 0067480 L W RS-399-A Page 2 and B) respectively. The recording starts with side 1 up; at i& conclusion, the compact cassette may be turned over and the recordin
15、g continued with side. 2. up. It may also be used for continuous reproduction, without having to turn over the compact cassette, by reversing the tape direction, 3.2 The back edge of the compact cassette shall be provided with two breakout lugs which, when re- moved, prevent accidental erasing of th
16、e relevant side. The relationship between the sides of the com- pact cassette and the breakout lugs is shown in figure Ad and B3 as indicated by arrows. These lugs shall be so constructed that they can withstand a perpendicular force of 3N (about 10.79 oz.) applied to the lug surface at a point defi
17、ned by the intersection of the Z datum and the lug center line. The lug shall not deflect greater than 0.40 mm (.O16 in.) with the applied force. 3.3 The compact cassette shall be provided with a pressure pad to hold the tape against the magnetic recordheproduce head. 3.4 The compact cassette shall
18、be provided with a magnetic shielding of the magnetic recordhepro- duce head. 3.5 The compact cassette may be provided with windows for observing the amount of wound and unwound tape. For maximum dimensions see figure A3 and B3. 3.6 The tape shall be fastened to the hubs and wound with the magnetic
19、coating facing out. 3.7 Recorded compact cassettes will accommodate lengths of tape as required by program content. Blank compact cassettes shall contain tape per the following table. Nominal totil Tape width Maximuni tape hliiiimum lape recording ti me thickness length in minutes mm in. mm in. mete
20、rs feet P 45 . 3.76 .148 .O20 .O008 64 211 3.81 .1SO 60 3.76 .148 .O20 .O008 86 282 3.81 .150 90 3.76 .148 .O15 ,0006 129 423 5.81 .15 120 3.76 .148 .O10 .O004 172 564 3.81 ,150 EIA 399-A 75 3234600 00674L 3 RS-899-A Page 3 a 4. DIMENSIONAL REQUIREMENTS 4.1 Figure Al, A2, and A3 are in inches. 4.2 F
21、igure B1, B2, and B3 are in millimeters. 5. GENERAL DRAWING NOTES 5.1 For explanation of drafting symbols used refer to American National Standards Institute, In. Standard Drafting Practice Y 14.5 (also see appendix). 5.2 For method of converting inches to millimeters and vice versa as used in this
22、standard refer tq International Organization for Standardization IS0 recommendation R370 reference number ANSI 2210.1-1913. 5.3 The X Datum Line defined as a line through the intersections of the centerlines and back edge of the two rectangular locating holes in the same plane. 5.4 The Y Datum Line:
23、 The compact cassette is symmetrically disposed about the Y Datum Line, which for the purpose of this standard is defuied as a line perpendicular to the X Datum Line, 5.5 The “Z” Datum Plane defined as exactly equidistant between the upper and lower support planes, which are defined between the resp
24、ective three control points. 5.6 Shaded areas designate controlled support planes. Flatness, parallelism and dimensional require- ments refer to these support planes only. d 5.7 Each surface feature, regardless of feature size, must be within 0.2 mm (.O08 inches) dia. of true position as referenced
25、to the corresporidiiig siirfaca feature o the opposii.c side (lia1 f ), 5.8 The compact cassette is symmetrically disposed abqut the “Y” datum line, and datum features are symmetrically disposed about their respective centerlines or edges to within half of the indicgted co- ordinate tolerances, unle
26、ss otherwise noted. 5.9 The tape guide limits within the compact cassette are indicated by the cross hatched area. 5.10 TYP (TYPICAL) indicates that the dimension so marked applies to identical undimensioned features disposed throughout the drawing. EIA 399-A 75 3234b00 0067482 5 RS-399-A Page 4 APP
27、ENDIX DRAFTING SYMBOLS -1 dimensions are basic or true position dimensions and, as such, are absolute and without tolerance, and are intended as a reference dimension only in the establishment of a particular datum. 1 d3 I B O I .XXX DIA, 0 1 each surface feature above and below the associated plane
28、 must be within .XXX dia. of true position, regardless of feature size, of its corresponding feature. In the case of holes, the axis of the holes (either surface) must be within a cylindrical tolerance zone .XXX dia. This .XXX dia. tolerance zone would be perpendicularto the associated datum plane.
29、In the case of features other than holes, the bound4ry edges are to be considered to be within .XXX dia. tolerance zone. - - 1-Y- I .XXX TOTAL the central plane of the dimensional feature must be within a toler- ance zone defined by two parallel planes,.XXX apart. The mid point of these planes is co
30、nsidered to be the associated datum, the support plane, as designated by FIG. 2 and B2 and note 5.5, must be flat within a tolerance zone as defined by two parallel planes .XXX apart, i,e. all surface irregularities of these support planes must be confined within the boundaries of the aforementioned
31、 tolerance zone. I 11 I -Z- I .XXX I parallel to the “2” datum plane within ablerance zone defined by two parallel planes .XXX apart and parallel to the “2” datum plane, the lower support planes, shown in FIG. A2 and B2 and note 5.5, must be EIA 377-A 75 m 3234600 O067483 7 m i?- n RS-399- A Page 5
32、EIA 399-A 75 m 3234600 0067484 9 m R S- 3 5 9- -4 Page 6 I f i f d I ? n w I- O z W W VJ I n i EIA 399-A 75 m 3234b00 0067485 O m i . $4 r 7: X I? 2 I / 1 1s-399-A Page 7 ? ! I n EIA 399-A 75 m 3234b00 00b74b 2 m RS-399-.1 Page 8 ! I F, I/ + -A) P EIA 399-A 75 W 3234600 0067487 4 m RELATED EIA STAND
33、ARDS In addition to this Standard, the following Standards on magnetic tape cartridges are available: RS-264 Magnetic Recording Tape Cartridge Dimensions $1 .O0 RS-332 Dimensional Standards - Endless Loop Magnetic Tape Cartridges, Types I, II and II1 2.60 For a FREE and complete listing of all current EIA and JEDEC Standards and Engineering Publications write: EIA Engineering Department Standards Orders 20Q1 Eye Street, N.W. Washington, D.C. 20006
