A seismic source signal generator includes a mass, a primary accumulator and a secondary accumulator, the secondary accumulator having an internal volume smaller than an internal volume of the primary accumulator. The cells in the connections are destination address modified not to send to the congested output port, but to continue sending to the other output ports in the connection. The second doped amorphous silicon layer is doped oppositely from the first doped amorphous silicon layer. The distal portion includes a helically wound wire and a tether coupled to the wire that is movable for causing the wire to buckle.