SYSTEM OVERVIEW

Following de-nationalisation of the U.K. rail industry, the new train operators realised the need to improve the customer interface on their train stock. The existing public address (PA) system, designed over 30 year ago, was deemed a major target for improvement. In conjunction with the former British Rail, GAI-Tronics. had developed a prototype replacement system for just such an eventuality.

SYSTEM FUNCTIONALITY

The requirement from ADTranz was to provide replacement PA receivers and additional transmitter points for 14 train sets for Midland Mainline, utilising the existing train wiring and retaining some original transmitter units.

The new system provides selected zonal addressing facilities for broadcast of PA messages and increased clarity via the new receivers.
A digital speech facility for pre announcement ‘jingles’ and a walk through test message facility.

Discrete crew to crew communications using different carrier frequencies to the PA, thus allowing simultaneous crew communications and PA.
The units are designed to occupy the same space envelope as the original units to simplify change over.

SYSTEM DIAGRAM



Illustration shows a typical simplified GAI-Tronics crew communications system incorporating all standard equipment.  Variations of the above are available