MONITORS FOR THE RAILWAYS

 

`                                                              The Peca Electronics range of Monitors for Driver Only applications on theRailways produce very bright, sharp and stable pictures. The inclusion of an OCLI coated 60% transmission panel bonded to the Cathode Ray Tube faceplate further enhances the visibility of the pictures under difficult outdoor lighting conditions. Image contrast is improved due to the dark appearance of the screen and surface reflections are reduced by the anti-reflection OCLI vacuum coated panel. This panel is bonded to the faceplate of the Cathode Ray Tube, to enable the reflections from the front surface of the tube to be suppressed. The panel also affords some degree of protection against vandalism. Picture visibility is also improved by the use of the Automatic Brightness and Contrast system which measures the level of ambient
light and  adjusts  the picture contrast and brightness to maintain a clear visible picture.

The Switch to Black system allows the monitor picture to be switched to
picture black when a train is not standing in the station, thus significantly improving Cathode Ray Tube life. The monitor is still powered, which means pictures are instantly available when required. To switch the picture off requires an external loop to be made, thus in the event of a fault condition, or disconnection of the interface circuit the monitor will revert to displaying pictures and therefore fails safe.

Use of monitor grade tubes with focus modulation, wideband video amplifiers
and black level clamped video, ensures that bright, crisp, high contrast images are displayed.

The monitors are available in 15” and 20” tube diagonal sizes in an open frame “Portrait” or “Landscape” style. A range of suitable housings are available from a number of suppliers. The “portrait” format gives the best use of the Television aspect ratio for looking down the side of trains.

Optional extras include Video Isolation Transformers for dealing with earth
loop problems, and a “Gamma” amplifier board, which stretches the signals near black and compresses the video near white, allowing improved handling of difficult lighting conditions such as a platform part in sun and part in shade.
 
 
 
 
 
 
 
 

 

KEY FEATURES

* High contrast with excellent EHT
  stability

* Dynamic Focus

* Automatic Brightness/Contrast

* Switch to Black interface

* Differential Hum-rejecting input

* Anti-glare OCLI panelled faceplates

* High resolution

 

SPECIFICATIONS

Picture Size:          15” or 20” diagonal

System:                  625 line 50Hz or 525 line 60Hz

Controls:                 Brightness and Contrast

                                    (Screwdriver adjustment)

Video Input:          1V  +/-3dB composite video, looped

                                differential, floating, hum rejecting

                                high impedance input with 75R

                                terminating/loop switch

Common Mode

Input  Rejection:     >50dB at 50/60Hz

Signal range:         <3V pk-pk

Bandwidth:              >10MHz +/-1dB

Resolution:              >800 TV lines (Not limiting resolution)

Switch to Black:      Short circuit external loop to

                              switch to black

                              Note: Alternative arrangements such

                                      as 50V DC is available on request)

Auto Brightness

/Contrast:                 Light sensors mounted at front of unit

                                adjust Brightness and Contrast of display

                                to compensate for changes in ambient

                                lighting from full sunlight to darkness

Horiz. Freq. pull in:     15.625KHz +/-550Hz

Vert. Freq. pull in:       50 or 60Hz +/-10%

Geometry:             Better than 2%

Supply:                 240V -10%/+6% at 45VA or

                               110V -10%/+6% at 45VA

Connectors:          BNC for Video, IEC for Mains,

                               RPC212P3S 3 pin miniature for Switch to Black

OPTIONS:            A  Video Isolating Transformer may

                               be supplied fitted to the Monitor to

                               improve the resilience of the system

                               to hum loops etc.