It operates on alternating and direct current and from a 15 volt battery. Calibrated in vertical position

ALICANTE

MADRID - PINTO INTERCITY CABLE

Burgos. Repeaters and test table.

Talavera. Primitive picture of the old urban network.

Madrid. Pinto. Materials warehouse. Intercity cable.

Threshing in Colmenar Viejo.

Straw hauling in Moralzarzal. Guadarrama.

TELEPHONE BULLETIN : INFORMATION BODY FOR EMPLOYEES OF THE NATIONAL TELEPHONE COMPANY OF SPAIN

PHOTO REPORT : FRONT VIEW OF THE EXTERIOR OF THE SAN RAFAEL TELEPHONE EXCHANGE AT THE REGIONAL DIRECTORATE OF MADRID

PHOTOGRAPHIC REPORT : SCHOOL OF SPLICERS OF THE NATIONAL TELEPHONE COMPANY OF SPAIN IN MADRID, PROMOTION OF THE YEAR 1943

PHOTOGRAPHIC REPORT : 1943 MANUAL MECHANICS COURSE OF THE NATIONAL TELEPHONE COMPANY OF SPAIN