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This was done because ] am not audibly providing the position of the decimal point.. By giving the user the contents of all V/i digits, the mental determination of the decimal point's placement is made easier

Circuit Description the MC14433 A/D converter chip [enclosed in the DMM) is the heart of the converter, The chip has BCD outputs available for the 3Vi digits, but they must be demultiplexed "off-chip" by using the display triggering lines Since the demultiplexing and selection of each digit is not available "on-chip/' the chip count of the DMM-to-Morse code converter is higher than for the Morse clock.

Since t have never tack led a complete project from the design stage to the building stage, various aspects of the MC14433 chip posed some minor stumbling blocks. After reading the article entitled "Super DVM" (August, 1977, issue of 73 Magazine), I selected a single 7474 {dual D fItp-flop) to demultiplex the Vt (first) digit and the minus sign. The 7474 chip solved the minor stumbling blocks.

The Minus Sign

The minus sign demultiplexing, sampling, storage, and recovery circuits are made up of U10A. U15D, U26A and B, U26C and D, and U27A (respectively).

When a minus jsign is present, the 7400 SR flipflop (U26A & B) provides the following actions: 1. Selects the appropriate is e v

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