S-VHS (Super Video
Home System) |
New format high resolution VHS video recorders, capable of giving greatly improved picture if all features are used. VHS compatible. |
| S-VHS+ |
A recording system that can playback a picture with a resolution of over 410 TVL. |
S.E.C.AM. (Systeme
Electronique
Couleur Avec
Memoire. See CCIR) |
Colour TV system used in France. |
S/N Ratio (Signal to
Noise Ratio) |
Measure of noise levels of a video signal; the higher the number the better. |
| Scanner |
A pan only unit. |
| SCART |
Standard European 20 pin connector used for carrying both video and audio signals in domestic TV appliances, now utilised on some CCTV equipment. |
SCSI (Small Computer
Standard Interface) |
A hardware bus interface that enables a single expansion board in the computer to be connected to up to 7 or 15 peripheral devices (hard disk, CD-ROM, Scanner, etc) |
| Secondary code |
Part of the security code stored in the access card which identifies the installation the card belongs to. |
| Serial Transmission |
Method of data transmission in which the bits of a data character are transmitted sequentially over a single channel. |
| Short-Haul Modem |
A data Communications Equipment (DCE) device that amplifies and conditions the data signal for transmission over cable for long distances. |
| Shutter |
An electronic circuit available on many CCD cameras. Allowing the light gathering period (1/50th of a second) of the camera to be stopped prematurely (as little as 100,000 of a second). |
Simplex
(Multiplexer) |
A multiplexer with 1 frame store that can either time multiplex records or show multi-screen pictures in live or play back. It cannot record the multiplexer pictures whilst showing multi-screen pictures. |
| Single-Mode Fibre |
An optical fibre that supports only one mode of light propagation above the cut off wavelength. The core diameters are usually between 5 and 10 micrometres (um). |
| Swivel Mount |
Used on a tower or bracket to enable the housing to be pointed at any angle, vertically or horizontally. |
Sync
(Synchronisation
pulses) |
Pulses generated, normally by the camera, to tell other pieces of equipment when a picture (field sync) or one line of a picture (line sync) is to start. |
