1、I % EIA 242 bl m 3234600 O063509 l m CORRECTION SHEET EfA Standard RS-242 Definitions for Electromagnetic Delay Lines The following corrections should be noted in thesubject Standard: Page 1 - Paragraph 2.2, first sentence should be reworded as follows: “The electrical parameters of the Delay Line a
2、re defined by the descriptions of the wave forms of the input, output and taps of the line and their relationships to each other“ Page 2 - Paragraph 3.7.2 delete “x 100“ Paragraph 3,7.3 de.lete “x 100“ e s CI 42 4 Y a EIA 242 bL m 3234b00 00b35LO 8 m / h - -=A HA STAWDARD 8s-242 (Reprinted December
3、1981) Enginsenng Deparment ELECTRONIC BNDUSTRIES ASSOCIATION EIA 242 61 3234600 OOb35LL T C J NOTICE EIA standarde are adopted in the public interest and are designed to eliminate misunder- standings between the manufacturer and the purchaser and to assist the purchaser in selecting and obtaining wi
4、thout delay the proper product for its particular need. Existence of such stand- ards doea not in any respect preclude any member or non-member of EIA from manufacturing or selling producta not conforming to the standard. Any propossl of recommended standards and practices made by the Association is
5、 without any regard to whether or not, their adoption may in any way involve patents on articles, materials or processes. By such action, the 2 AUEncompasring. . s (%) where Id1 represente peak post pulse distortion. Defined as the largest peak amplitude of all spurious responses either in the posit
6、ive or negative direction relative to the pulse amplitude. Cabulted in %. where lbl, ICI or Id1 represents largest - peak amplitudes. . lbl or ICI or ldl E S(%)=* a -. EIA 242 bb E 3234b00 00b3513 3 7 RS-242 Pago 2 3.2 Impednnce 3.2.1 Churacteristie Impedance. . Z, That value of terminating impedanc
7、e which provides minimum reflections to the input of the line. 3.2.2 Sourcelmpedance Z The impedance of the pulse source as seen by the delay line input terminals. The impedance of the load as seen by the delay line output terminals. 3.2.3 Terminating lmpedanc . Z 3.3 Pnlee Amplitude (see figures) .
8、 .E 3.4 Temperature Coefncient of Delay. .T, 3.41 Parts per million per degree centigrade (PPMOC) 3.4.2 Microsecond per microsecond per degree centigrade. (usec/usecC) 3.43 Percent per degree centigrade . (%/OC) Expressed in % as: . h (%) The change in delay with temperature expressed as : Or? or, 3
9、.5 Tllt,.,.h h (%) =*EX lhl 100 where lhl is absolute value of height of tilt axis. 3.6 Time 3.6.1 Delly Line FaU Time . .ti The time of tke amplitude decreasing edge of the output pulse assuming a stepfunction input. 3.6.2 Delay Line Rbe Time. . t, The time of the amplitude increasing edge of the o
10、utput pulse afieuming a step-function input. 3.6.8 I)elayTe ta Elapsed time between the 60% amplitude of the leading edges (refer to point 1 on all figures) of the delay line input and output pulses or between an otherwise designated input and output point. 3.6.4 p.(db) = 20 logm - Eni Eno d Num3 4.
11、1 Figure 1 - General case. 42 Figure 2 -Where tilt is essentially O (=?o), the axis of oscillation Will be horizontal, elimi- nating the need of establishing intersection points 2 and 3 of Figure 1. 43 3 - Where pulse width is narrowed to the point where no axis of oscillation (Ap) can be esta lishe
12、d then the pulse amplitude (E) will be considered as the peak of the pulse. EIA 242 61 3234600 0063514 5 = RS-242 Page 3 i I t d.-b -t- TIME AXIS Ar TANQENT TO LEADINO EWE At - TANGENT TO TRAKIW6 DOE Ap - AXIS OF OSCILLATION I - REFERENCE POINT FOR MEASUREMENT OF DELAY (T) 2 - INTERSECTION OF Ar AND #p 3 - INTERSECTION OF AI ANO Ap GENERAL CASE Figure 1 Y- EIA 242 bL = 3234b00 00b35L5 7 RS-242 Page 4 SPECIAL CASE I Flgure 2 SPECIAL CASE Flgure 3 Il
