| 摘要 |
PURPOSE:To enable to perform automatic readout of error production to the automatic reader, by compulsively inserting white video signal to the specific part of one line video signal at the transmission side in advance and recording the error mark on the white video signal section at the reception side. CONSTITUTION:The differentiation pulse generating circuit 2 detects the start of cut-out signal for one scanning line from the video signal generator 1 at the transmission side and differentiation pulse is transmitted to the latch circuit 3. Further, the gate circuit 5 is controlled with the output of the circuit 3 and white video signal is compulsively ttransmitted to the specific part of one scanning line independently of the video signal of the generator 1. Thus, the video signal masked with white signal for several dots from the start of cut-out is transmitted to the line via the coder 7 and the modulator 8 every line. At the reception side, every time the decoder 12 detects the error line, error pulse is produced, and this pulse is latched with the latch circuit and the gate circuit 20 is closed with this latch output, and the error mark signal of black signal is compulsively fed to the recorder 21 independently of the video signal and recorded on the recording paper. |
