This circuit, which can serve as a reference for restorations, was found in the October 1989 issue of Radio Electronics magazine. The circuit uses a 5-digit display and a dedicated integrated circuit.
Analog Devices AD7768 24-bit sigma-delta (Σ-Δ) ADCs include an Σ-Δ modulator and digital filter...
This circuit was obtained in a Popular Electronics of 1991. The magazine no longer exists, but the...
We found this circuit in a Radio Electronics magazine from April 1988; The output timing is given...