Porthcurno Telegraph Museum

Instrument Room

Porthcurno Telegraph Museum's instrument room replicates, using original equipment, a complete working telegraph cable circuit with all the equipment needed to automatically send a message from one station to another. One end of the room represents London, the other Cape Town, with a relay station in the middle

The wall-mouted black and white photos show Porthcurno operatives at work. Two photos (one on the wall with the map and the other on the wall with the clocks) show Porthcurno worker Derek Moore 'taking a margin' which involves checking the quality of received signals. The photo on the opposite wall (the man standing in front of instrument cabinets and looking up) shows Malcolm Jones adjusting a clock-controlled reed.

All of the instruments in this room date from the 1920s and 1930s. The two wall-mounted clocks were used to ensure that the instrument motors all ran at the correct speed and the instruments on the benches to either side with the black cylinders are 'twin direct writing siphon recorders' - used to record transmitted and received signals onto paper tape.