Telephony equipment in the old post office
After this building was completed in 1924, all the services of the PTT (Post Telegraaf and Telephone) were successively moved in. In 1926, telephony services started in this building with 4400 customers from the city of Utrecht who were connected to a new automatic exchange. These connections used to be in the old manual switchboard on the Voorstraat. There was also an interlocal hand exchange with telephone operators for calling places outside the city of Utrecht. It used to be on Westerstraat.
From 1960 onwards, telephone equipment rapidly took up all the rooms in the building, except for the post office. There were more and more cables, power stations, batteries, connections to other power stations and so on. The enormous weight of that equipment, but also the copper cables used, even caused cracks in the building, resulting in a risk of collapse. By hastily reinforcing the building, this danger was averted in time.
As with computers, the equipment became increasingly smaller and more powerful from the 1990s due to digitization. In addition, replacing copper cable with fiber optic resulted in major space and weight savings. As a result, all the necessary equipment to provide the center of Utrecht with telephony, internet and TV is now concentrated in a corner of the basement.