Electrical discharge tube having trigger wires

An electrical discharge tube comprising:

• a cylindrical body, made of insulating material, having an inner surface, and having upper and lower end faces defining respective upper and lower openings;
• upper and lower metallized layers formed on the respective upper and lower end faces of the cylindrical body, the upper and lower metallized layers being substantially in parallel to each other;
• upper and lower electrodes for airtightly closing the respective upper and lower openings by means of the metallized layers, the upper and lower electrodes having respective electrical discharge faces, between which an electrical discharge gap is defined;
• a first electrical discharge trigger wire formed as a loop on the inner surface of the cylindrical body and extending substantially in parallel to the first and second metallized layers along a first surface located within a range of the electrical discharge gap;
• one or more second electrical discharge trigger wire formed on the inner surface of the cylindrical body and extending from the upper metallized layer to a fourth surface located between a second surface including the electrical discharge face of the upper electrode and the upper metallized layer;
• and
• one or more, other, second electrical discharge trigger wire formed on the inner surface of the cylindrical body and extending from the lower metallized layer to a fifth surface located between a third surface including the electrical discharge face of the lower electrode and the lower metallized layer.