| 摘要 |
PURPOSE:To attain the manufacturing of a store and forward switching equipment used in a transmission circuit in a form of light, thin, short and small, by recording a frequency value corresponding specifically to a bit of information to be recorded one by one in a pulse shape. CONSTITUTION:Since 256 pieces of individual codes are present in an ASCII used as a recording code constituting on code with eight bits, it is defined that ASCIIOO-7F are expressed as 4,288-4,796Hz, and ASCII80-FF as 4,804-5,312Hz. And at every appearance of an ASCII data to be recorded, a corresponding defined frequency value wave is recorded as the continuance of a pulse shaped wave for one cycle, and a center frequency wave of 4,800Hz is used in stead of an Index.Gap, eliminating a non-record part, and a noiseproof characteristic is improved. A modulator 4 executes the above operation, and also, as for a reproduction instruction, the cycle measurement of the read output wave of a recording and reproducing head 1 is executed at every cycle with a demodulator 3, then a frequency value being calculated, and a corresponding defined ASCII is retrieved and extracted, and a recording data is restored.
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