teletext:start

Teletext broadcast equipment

I picked up some Teletext broadcasting equipment at the 2021 S4C auction. This page chronicles my attempts to make some use of it.

I currently have:

I'm also working on an Intelfax/Starfish Atom Mk.II, and trying to load my own pages onto it.

I'm looking for a manual or some configuration details for this unit – please email me on philpem@gmail.com if you have any information.

This seems to be some kind of Teletext data bridge. Configuration is by internal DIP switches.

VG Electronics later became VG Broadcast, who became Sysmedia, who were bought by Screen Subtitling Systems, who in turn were bought by Broadstream.

According to Colin Hinson's Teletext pages, VG stands for “Vacuum Generators”. This ties in with the VG logo sometimes appearing on surplus high-vacuum equipment. That part of VG is now VACGEN.

I'm looking for the documentation for the Softel SE3055 Databridge – if you have a copy of this, please contact me on philpem@gmail.com

This is a 4-input Teletext data bridge.

It takes the Teletext data from four inputs and merges it into the main video feed – which in turn may also contain Teletext data lines.

The SE3055 is available in at least two main hardware variants.

  • EPROM configuration. The Databridge configuration is stored in a 27C256 EPROM. These units will not respond to the “Upload from Databridge” and “Download to Databridge” commands in the Softel SETUP software. The serial port will only function as an error/alarm log port (9600-8N1, with line-feeds).
  • EEPROM configuration. The Databridge configuration is stored in a 27C16A EEPROM. These units have later software which implements the ?. DOWNLOAD and UPLOAD commands. These units can be reconfigured on-the-fly.

My EEPROM unit has a “Rev 3” main PCB; my EPROM units have “Rev 2” main PCBs.

ROM versions are as follows:

  • Input block firmware: All my units have 157-x14 ROMs – these appear to be version 14.
    • The x is 1, 2, 3 or 4, corresponding to the Databridge input port number. Only the last byte of the ROM differs:
      • Hex 32 for Input 1
      • Hex 34 for Input 2
      • Hex 36 for Input 3
      • Hex 38 for Input 4
  • Main block firmware:
    • My EPROM-configured units are fitted with 157-507 ROMs.

The SE3055 is configured through an RS232 serial port (9600 Baud, 8 data bits, no parity, 1 stop bit), using a DOS application called “SETUP”.

The configuration tool can be downloaded here: softel_se305x_config.zip. It works with the following Softel devices:

  • SE3055 Multi-input Databridge
  • SE3054 Single-input Databridge
  • SE3031 NEWFOR Subtitle Inserter

Details in this section are from the Softel SE3055 databridge sell sheet (archive link)

This unit is designed to bridge teletext data from one video source to another. The SE3055 has four seperate data inputs, whilst the SE3054 has one. Both units can also insert synchronous data signals into the main video path.

Facilities

  • Broadcast quality video path and data insertion
  • Alarm outputs
  • Selectable line bridging, shifting and blanking
  • TV lines 6-22 and 318-335 capability
  • Data regeneration on all inputs
  • Data error rate monitoring
  • Dynamic VBI buffering
  • Optional PDC facility

Each TV line in the main video path field blanking interval can be specifically configured to contain data originating from any selected data or video input. Lines may also be blanked or passed as required.

All functionality, configuration and fault handling may be set up via RS232 connection from a PC configuration program.

Technical Specification

TV Standard 625 Line PAL/SECAM
Teletext Standard World Standard 6.9375 Mhz data rate
Inputs Video A
Video B (Synchronous input e.g ITS)
Data 1-4 (Asynchronous data & video), (SE3054 1 only)
Output Video A + Inserted data (two outputs)
Data only (two outputs)
Sync.
Video Path Full broadcast specification. Automatic bypass on power failure
Data Path All data inputs are fully regenerated to broadcast standard
Configuration By user programmable PC software via RS232 port
Line Blanking Any valid Teletext line
Line Bridging Any data line on inputs 1-4 may be selected for transfer to any line on the main video
Framing Code Any valid framing code can be selected for each data input 1-4
VBI buffer Individually programmable data input buffers to cope with loss of main video, asynchronous cuts and input/output sync differential
Alarms Alarm relays may be triggered by data error rates, input signal failure and loss of video
Apology Programmable apology captions selectable for each input
Data Timing Default data timing adjustable from front panel
Internal Sync On loss of main video, the unit will switch to internal sync
Front Panel LED indicators for power, data inputs, main video, system alarm and bypass status
Alarm Outputs Configurable relay contacts
Serial Port 9-way D-type RS232 connection for fault logging or PC configuration
Power 80-240V 50/60 Hz IEC Mains input 150W
Mechanical 1U rack mounting, 490mm(D), 5kg

I'm looking for manuals and/or software for this machine – especially a way to upload Teletext pages to it. Please email philpem@gmail.com.

The ATOM is a Teletext data inserter. This was designed by Intelfax and later continued by Starfish Technologies.

According to the archived Atom Mk2 web page, ATOM means “Advanced Teletext Origination Module”

It runs Windows 2000, on a Pentium MMX processor board, with a custom outboard Teletext generator connected over the PC/104 bus.

Datasheet

It can manage up to 16 Teletext magazines (with up to 8 on air at a time), and can store a total of 8000 Teletext pages which can be mapped for transmission as required.

The software consists of a Teletext encoder driver, a system service (ATOM.exe) and a management UI (AtomManager.exe).

The datasheet suggests that the Atom can accept data over RS232, but the Atom I worked with doesn't seem to do this.

The ATOM.exe service listens to the following TCP ports:

Protocol Port Function Description
TCP 5000 DataInputSocket
TCP 56000 RawInputSocket
TCP 56001 RawOutputSocket
TCP 56663 BBC2DataInputSocket
TCP 56664 EngineeringSocket
TCP 56665 SendToCompanionSocket
ReceiveFromCompanionSocket
Send data to - or receive data from - a companion ATOM.
This seems to allow two ATOMs to operate in a redundant (primary and backup) setup.

The function names are those used in the ATOM executable

A timer runs every 800ms to perform some housekeeping functions.

Newfor is a protocol used to transfer subtitles to Teletext inserters. It is implemented in VBIT2's 'newfor.cpp' file.

newfor-subtitles can play SRT files in TCP/IP Newfor format.

EP1 is a file format used to store Teletext pages.

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  • Last modified: 2022/09/21 08:06
  • by philpem