Service manual

STP 11-25R13-SM-TG
Glossary - 18
flux
(1) The lines of force, which make up an electrostatic field. (2) A substance used to facilitate fusion,
such as a material that removes oxides from surfaces to be joined by soldering, brazing, or welding. The
flux also reduces surface tension of the molten solder and metal to be soldered and it covers the material
being soldered to prevent reoxidation of the surface during the soldering operation.
focus
The point at which light rays or an electron beam forms a minimum size spot.
footcandles (fc)
Unit of illuminance.
frame
(1) The smallest picture unit in film, a single picture. (2) A complete scanning cycle of the electron
beam (two fields), which occurs every one-thirtieth of a second. (3) The total picture area that is
scanned while the picture signal is not blanked. A single, complete television picture.
frequency (freq)
The number of recurrences of a periodic phenomenon in a unit of time.
frequency response
Defines the performance or behavior of a filter, antenna system, microphone, speaker, or headphone.
front porch
Portion of the composite picture signal which lies between the leading edge of the horizontal blanking
pulse and the leading edge of the corresponding horizontal sync pulse.
gamma
Correction required compensating for the non-linear characteristics of the monitor CRT.
ghost
A shadow or weak image in the received picture, offset either to the left or right of the primary, the result
of transmission conditions which create secondary signals that are received earlier or other than the main
or primary signal.
gigahertz (GHz)
Frequency unit of 1 billion hertz.
glitch
A form of low frequency interference, appearing as a narrow horizontal bar moving vertically through the
picture, or noise bursts or dropouts in an audio signal.
ground loop
(1) An unwanted feedback condition in which power current in a single ground wire causes instability or
errors. (2) A condition when two or more paths to ground exist and a voltage is induced unequally in
these paths, causing interference like hum, buzz, or noise, where a difference in potential exists between
two or more ground paths due to the resistance of the ground conductors.
hertz (Hz)
Standard unit of frequency.
horizontal (hor) rate
The time for scanning one complete horizontal line, including trace and retrace. NTSC specifications say
this equals 1/15734 second (color) or 63.56 microseconds.