Central battery switchboard, can be used for the service of subscribers in manual central battery centres or in those equipped with automatic service. The capacity of these switchboards is from 3 to 5 extension lines, and can be extended...

Manual, local battery and magneto telephone switchboard. Equipped with 5 outside lines, 25 inside lines (5 long line circuits and 25 short line circuits) and 5 cord circuits. Model made of wood, consisting of a box with a switchboard system.

GRAN VÍA 28 BUILDING

AMPLIFIER

This model has a radio frequency range between 10 and 500Mc with an output of 0.1 microvolts to o.1 volts. The AM range is from 0 to 30% and an AM distortion at 5% from 10 to 250Mc and at 7% from 250 to 500Mc. On the other hand the FM range is from 0 to...

This model is designed for general measurement work, audio, loudspeaker and amplifier testing and frequency comparisons. It contains a built-in 3 watt amplifier. The output signal level is at a constant level of...

Sama de Langreo. Central.

ERICOFON AUTOMATIC CENTRAL BATTERY TELEPHONE

A teletype used in the 1950s for the transmission of data and typed messages over simple communication channels such as the pair of telegraph wires

4. Suppose it is the number 2859. Insert your finger vertically into the hole corresponding to the number 2.

Demonstration of the automatic.

COASTAL STATIONS : MACHICHACO COASTAL STATION

COAXIAL CABLE : SPLICING PROCESS

COAXIAL CABLE : SPLICING PROCESS

MECHANISED SECTION : INVOICING DEPARTMENT

MECHANISED SECTION : PAYROLL