Print head of a continuous ink jet printer comprising: - a cavity for the circulation of jets, delimited laterally by side walls (9, 10), - means (4, 4 1, 4 x, 4 n) for producing at least one ink jet in said cavity, - means of charging, for applying a charge to at least one ink jet produced by the means (4, 4 1, 4 x, 4 n) for producing at least one ink jet in said cavity, - at least one electrode for deviating, for sorting drops or segments of one or several of said jets intended for printing from drops or segments that are not used for printing, - a slot, open onto the exterior of the cavity and allowing the exiting of the drops or segment of ink intended for printing, - a 1 st gutter for recovering drops or segments not intended for printing, - a 2 nd gutter for recovering drops or segments that are not deflected and not intended for printing, this 2 nd gutter being mobile and comprising an input slot and at least one suction channel, - means for actuating in order to actuate the 2 nd gutter for recovering in movement between a retracted position, in which it does not close off the outlet slot of the cavity, and a closed position, in which its input slot faces the outlet slot of the cavity, in such a way that a non-deflected jet, produced by the means for producing at least one ink jet in said cavity, exits via the outlet slot and enters into the input slot of the 2 nd gutter for recovering, - conductive means, for detecting an electrical charge of drops recovered in the 2 nd gutter for recovering when the latter is in the closed position and/or conductive means (101a, 103, 103d, 103g) in order to detect, without contact, the passing of charged drops when the 2 nd gutter is in the open position. - a cavity for the circulation of jets, delimited laterally by side walls (9, 10), - means (4, 4 1, 4 x, 4 n) for producing at least one ink jet in said cavity, - means of charging, for applying a charge to at least one ink jet produced by the means (4, 4 1, 4 x, 4 n) for producing at least one ink jet in said cavity, - at least one electrode for deviating, for sorting drops or segments of one or several of said jets intended for printing from drops or segments that are not used for printing, - a slot, open onto the exterior of the cavity and allowing the exiting of the drops or segment of ink intended for printing, - a 1 st gutter for recovering drops or segments not intended for printing, - a 2 nd gutter for recovering drops or segments that are not deflected and not intended for printing, this 2 nd gutter being mobile and comprising an input slot and at least one suction channel, - means for actuating in order to actuate the 2 nd gutter for recovering in movement between a retracted position, in which it does not close off the outlet slot of the cavity, and a closed position, in which its input slot faces the outlet slot of the cavity, in such a way that a non-deflected jet, produced by the means for producing at least one ink jet in said cavity, exits via the outlet slot and enters into the input slot of the 2 nd gutter for recovering, - conductive means, for detecting an electrical charge of drops recovered in the 2 nd gutter for recovering when the latter is in the closed position and/or conductive means (101a, 103, 103d, 103g) in order to detect, without contact, the passing of charged drops when the 2 nd gutter is in the open position.