NTSC Degrees to Nanoseconds to Cable Length
Degrees of	Time in	% Vel. of Prop.
Subcarrier	Nanoseconds	Cable length in feet
		66%	78%	82%
1	0.776	0.5	0.6	0.63
2	1.552	1	1.2	1.25
3	2.328	1.5	1.8	1.9
4	3.104	2	2.4	2.5
5	3.88	2.5	3	3.1
6	4.656	3	3.6	3.8
7	5.432	3.5	4.2	4.4
8	6.208	4	4.8	5
9	6.984	4.5	5.4	5.6
10	7.76	5	6	6.3
20	15.52	10.1	11.9	12.1
30	23.28	15.1	17.9	18.8
40	31.04	20.1	23.8	25
50	38.801	25.2	29.8	31.3
100	77.601	50.4	59.6	62.6
200	155.203	100.7	119.2	125.2
300	232.804	151.1	178.8	187.9
360	279.365	181.3	214.6	225.4
(NTSC subcarrier frequency is 3.579545 MHz, or 1 cycle or subcarrier every 0.0000002793 seconds.
That's one full cycle or 360 degrees, so 1 degree of subcarriers 0.000000000776 seconds or 0.776 nanoseconds.
These numbers have been rounded off, but accuracy here is enough to time a video system within .025 degrees.)