Underwater detonating device

Control system for sound actuation of ignition devices, comprising:

• a digital logic part;
• means producing two frequency and time correlated input signals;
• an analog pressure wave receiver comprising a hydrophone, a preamplifier connected to said hydrophone, a band-pass filter connected to said preamplifier, a buffer amplifier connected to said band-pass filter, and two parallel selective filters connected to said buffer amplifier and having outputs with logic level for processing in said digital logic part;
• said digital logic part connected to said analog pressure wave receiver;
• dual driver stages connected to said digital logic part;
• and
• first and second discharge circuits connected in parallel, said first discharge circuit connected to the dual driver stages and to a detonator and a voltage supply and suitable for selectively igniting the detonator and the second discharge circuit for short circuiting the voltage supply, and wherein said digital logic part activates said first and second discharge circuits in successive time intervals (t.sub.1, t.sub.2, t.sub.3) depending on said means producing two frequency and time correlated input signals;
• and
• said two parallel selective filters comprise in their filter channel in each case in series connection a filter element, an emitter follower and a Schmitt-trigger.