a transmission floor having a plurality of rollers positioned at two sides thereof;

a board positioned on the rollers, the board comprising an I/O (input/output) circuit for electrically connecting to a device to be tested, and a first connector electrically connected to the I/O circuit;

a stopping unit positioned at the transmission floor; and

a testing device positioned beside the transmission floor, the testing device comprising a second connector matable with the first connector;

wherein the second connector is configured to move and connect with the first connector and thereby form a plurality of signal channels in cooperation with the first connector; the first connector comprises a plurality of metal pads arranged in an array, and the second connector comprises a plurality of metal probes arranged in an array corresponding to the array of the first connector;

wherein a first positioning mechanism is used to adjust the position of the second connector relative to the first connector,

wherein the first positioning mechanism comprises a positioning post a with tapered bottom end provided with the second connector, and a positioning hole corresponding to the positioning post provided with the first connector, a diameter of the positioning hole being slightly greater than a diameter the positioning post; and the positioning post is longer than the metal probes; and

wherein the second connector further comprises a first air driven device configured for moving the metal probes to connect with the metal pads of the first connector, and the second positioning mechanism comprises a second air driven device having a positioning head, the second air driven device being configured for moving the positioning head and thereby adjusting a position of the board relative to the testing device.