This method of operation and equipment, unique to this line, was originally used only through the two single line tunnels on this line, at Ledbury; and under the Malvern Hills between a former signal box at Colwall to the signal box at Malvern Wells.
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A new additional telephone system was introduced in 2012 with the advent of GSM-R this is a GSM, 3G telephone system that allows signallers to contact the train crew by voice or text and can link into the communication systems used by the British police, fire and ambulance services.
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