Figure 5-21.-TDS Interface block diagram.
Transmitting devices include coaxial lines, low- or
high-power transmitters, or microwave relay links.
The reproducing device is a television receiver, a
television monitor, or some form of electro-optical
This chapter will discuss the camera tubes
(pickup devices) and picture tubes (reproducing
devices). For most uses in aircraft, coaxial cables
provide the means for transmitting the video signals
from the pickup to reproducing devices.
Television transmission of a picture from one
point to another involves a process in which light,
reflected from an object or scene, is converted into
electrical impulses of varying magnitude. This
process is accomplished by means of synchronized
scanning. In synchronized scanning, the picture is
examined by the camera and reproduced by the
viewing monitor. This is done point-to-point and in a
regular pattern. The process is carried out so rapidly
that the entire picture is scanned many times each
second, and the eye sees it as a single complete image.
The basic television system is shown in
figure 5-22. Notice that it consists of a transmitter
and a monitor. An image of the scene is focused on
the camera pickup device. An electron beam in the
device scans the optical image and produces an
Figure 5-22.-Basic television system.