CCIR System D is an analog broadcast television system used in the Commonwealth of Independent States, parts of Eastern Europe and People's Republic of China.[1][2]
This was the first 625-line system, developed by Mark Iosifovich Krivosheev in 1948,[3][4] and later associated with the SECAM and PAL color systems. Used on VHF only in most countries, it's usually combined with system K on UHF. In China it is used for both VHF and UHF.
Specifications
Some of the important specs are listed below:
System D specifications
Frame rate
|
Interlace
|
Field rate
|
Line/frame
|
Line rate
|
Visual b/w
|
Vision mod.
|
Preemphasis
|
Sound mod.
|
Sound offset
|
Channel b/w
|
25 |
2/1 |
50 |
625 |
15625 |
6 MHz. |
Neg. |
|
FM |
+6.5 MHz. |
8 MHz.
|
Television channels were arranged as follows:[5][6]
Original OIR assignments
System D 625 lines
Channel |
Video carrier (MHz) |
Audio carrier (MHz)
|
I |
41.75 |
48.25
|
II |
49.75 |
56.25
|
III |
59.25 |
65.75
|
IV |
77.25 |
83.75
|
1 |
145.25 |
151.75
|
2 |
153.25 |
159.75
|
3 |
161.25 |
167.75
|
4 |
169.25 |
175.75
|
5 |
177.25 |
183.75
|
6 |
185.25 |
191.75
|
7 |
193.25 |
199.75
|
8 |
201.25 |
207.75
|
9 |
209.25 |
215.75
|
Assignments since 1965
System D 625 lines
Channel |
Video carrier (MHz) |
Audio carrier (MHz)
|
1 |
49.75 |
56.25
|
2 |
59.25 |
65.75
|
3 |
77.25 |
83.75
|
4 |
85.25 |
91.75
|
5 |
93.25 |
99.75
|
6 |
175.25 |
181.75
|
7 |
183.25 |
189.75
|
8 |
191.25 |
197.75
|
9 |
199.25 |
205.75
|
10 |
207.25 |
213.75
|
11 |
215.25 |
221.75
|
12 |
223.25 |
229.75
|
Channel arrangement for China
Channel |
Frequency range (MHz) |
Video carrier (MHz) |
Audio carrier (MHz) |
DTMB center frequency (MHz)
|
Band I
|
1 |
48.5-56.5 |
49.75 |
56.25 |
52.5
|
2 |
56.5-64.5 |
57.75 |
64.25 |
60.5
|
3 |
64.5-72.5 |
65.75 |
72.25 |
68.5
|
4 |
76-84 |
77.25 |
83.75 |
80
|
5 |
84-92 |
85.25 |
91.75 |
88
|
Band III
|
6 |
167-175 |
168.25 |
174.25 |
171
|
7 |
175-183 |
176.25 |
182.75 |
179
|
8 |
183-191 |
184.25 |
190.75 |
187
|
9 |
191-199 |
192.25 |
198.75 |
195
|
10 |
199-207 |
200.25 |
206.75 |
203
|
11 |
207-215 |
208.25 |
214.75 |
211
|
12 |
215-223 |
216.25 |
222.75 |
219
|
System D 625 lines
Ch |
Video (MHz)
|
DTMB (MHz) |
Audio (MHz)
|
13 |
471.25
|
474 |
477.75
|
14 |
479.25
|
482 |
485.75
|
15 |
487.25
|
490 |
493.75
|
16 |
495.25
|
498 |
501.75
|
17 |
503.25
|
506 |
509.75
|
18 |
511.25
|
514 |
517.75
|
19 |
519.25
|
522 |
525.75
|
20 |
527.25
|
530 |
533.75
|
21 |
535.25
|
538 |
541.75
|
22 |
543.25
|
546 |
549.75
|
23 |
551.25
|
554 |
557.75
|
24 |
559.25
|
562 |
565.75
|
25 |
605.25
|
610 |
611.75
|
26 |
613.25
|
618 |
619.75
|
27 |
621.25
|
626 |
627.75
|
28 |
629.25
|
634 |
635.75
|
29 |
637.25
|
642 |
643.75
|
30 |
645.25
|
650 |
651.75
|
31 |
653.25
|
658 |
659.75
|
32 |
661.25
|
666 |
667.75
|
33 |
669.25
|
674 |
675.75
|
34 |
677.25
|
682 |
683.75
|
35 |
685.25
|
690 |
691.75
|
36 |
693.25
|
698 |
699.75
|
37 |
701.25
|
706 |
707.75
|
38 |
709.25
|
714 |
715.75
|
39 |
717.25
|
722 |
723.75
|
40 |
725.25
|
730 |
731.75
|
41 |
733.25
|
738 |
739.75
|
42 |
741.25
|
746 |
747.75
|
43 |
749.25
|
754 |
755.75
|
44 |
757.25
|
762 |
763.75
|
45 |
765.25
|
770 |
771.75
|
46 |
773.25
|
778 |
779.75
|
47 |
781.25
|
786 |
787.75
|
48 |
789.25
|
794 |
795.75
|
49 |
797.25
|
802 |
803.75
|
50 |
805.25
|
810 |
811.75
|
51 |
813.25
|
818 |
819.75
|
52 |
821.25
|
826 |
827.75
|
53 |
829.25
|
834 |
835.75
|
54 |
837.25
|
842 |
843.75
|
55 |
845.25
|
850 |
851.75
|
56 |
853.25
|
858 |
859.75
|
57 |
861.25
|
866 |
867.75
|
58 |
871.25
|
874 |
877.75
|
59 |
879.25
|
882 |
885.75
|
60 |
887.25
|
890 |
893.75
|
61 |
895.25
|
898 |
901.75
|
62 |
903.25
|
906 |
909.75
|
- The original assignments of channels 25 to 57 were 2 MHz higher in frequency until c.1984. Channels 58 to 62 were deleted at this time.