Figure 5 shows the basic responses to a step function (a) for an overdamped (b), critically damped (c), and underdamped (d) system. In any given TV set one might expect any one of these states to occur, depending on the Q of the bandpass, peaking effects, and saturation of color.
Figure 5e depicts a brief video pulse and the possible responses of the chroma section to it in (f). Responses 1 and 2 will show very little saturation as well as color smearing, while response 3 will exhibit more saturation but with a reduced color "echo" on the right side of a vertical edge, with possible cancellation of the chroma entirely.
The minimum duration of a chroma pulse through a 0.6 Mhz filter would be about 1.66 microseconds, allowing a true color resolution of only about 50 pixels per line. The TV game designer working for a home TV should realize that overall color detail will notbe very good, and that most of the fine detail must be carried by the Y channel.
Horizontal control jitter. Most TV games today use analog potentiometers as controllers, with mainly vertical motion only. Since the vertical resolution is so much greater than horizontal attempts to use pots to control sideways motion have resulted in "jittery" control which is difficult to place exactly.
As can be seen in Figure 6, a given spot location on the CRT raster is continuously defined to within 1 spot width, and an edge can start more or less anywhere on the line. However, in digital displays, the horizontal positions are quantized and restricted to discrete locations, as in (c). Thus, an analog control with continuous function to define location will try to locate an edge at a non-existent position (d). The resultant action can be an annoying jump of the paddle from one adjacent cell to the next.
The obvious solution to the problem is to add hysteresis in either hardware or software form. Until horizontal resolution increase to the point of vertical this jitter will be primarily a horizontal phenomena. Some approaches to digital controls solve the problem at the expense of "direct" player control of the location, but this can adversely affect playing action in the game.
Let it be noted that continuous function controls (i.e. pots) versus "up/down" or "left/right" button types require substantially different player skills, a fact which can augment or defeat a given game concept.
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