Broadcast

Technical Specification

• Teletext System - World System Teletext
  625 line EBU SPB 492
  CCIR Teletext System B
• Video in, Video Out, Monitor Out - 1Volt Composite into 75R BNC connectors
• Inputs A to D - 1Volt Composite BNC loop through - unterminated
• Inputs E and F - 1Volt Composite 75W terminated BNC connectors
• Insertion Gain - 0dB ± 0.1dB adjustable
• Frequency Response - 0-6 MHz ± 0.1dB
• Linear Distortion - 2T pulse and bar ratio < ± 0.5%
  Tilt < 0.25%K
  Chroma/Luma Gain inequality < 1%
  Chroma/Luma delay inequality < 10nS
• Non-Linear Distortion - Differential Phase < 1°
  Differential Gain < 1%
• Return Loss - > 36dB
• Signal/Noise Ratio - > 65dB rms ( 0.2 - 5.5 MHz )
• Amplitude - 462 mV adjustable ± 20%
• Filter - 100% roll off cosine
• Threshold - 150mV below black level
• Sync to Text delay - 12 µS, front panel adjustable
• Dimensions - 1U rack-mounting. 482mm wide, 44mm high, 277mm deep

Hardware

The ATP600 is a 1U rack-mounting unit. Most of the circuitry is contained on a single PCB.

A second PCB mounted on the front panel provides the interface to the switches LCD display and LED indicators.

A toroidal transformer and power supply are mounted onto the case. The unit contains no fans or disks and dissipates less than 10 watts. No special ventilation measures are therefore necessary.

The unit contains 1Mbyte of battery-backed memory storing both teletext pages and operating parameters. Data is retained for up to 72 hours without power and the unit resumes operation as soon as power is restored. A bypass relay operates to connect the video input to video output if power is removed from the unit.