centrex 7 Associations

central (generic term) telephone exchange (generic term) exchange (generic term)

patchboard 10 Associations

switchboard plugboard central (generic term) telephone exchange (generic term) exchange (generic term)

plugboard 9 Associations

switchboard patchboard central (generic term) telephone exchange (generic term) exchange (generic term)

switchboard 11 Associations

patchboard plugboard central (generic term) telephone exchange (generic term) exchange (generic term)