Dongfanghong Semiconductor Musical Instrument Version 3 (Reverse Engineering of Dongfanghong-1 Satellite Music System)

This project aims to reproduce the music system part of the Dongfanghong-1 artificial earth satellite telemetry system based on published historical image data and paper data.

The expected goal is to create a circuit that can automatically play the first three lines of "The East is Red" without using any microcontrollers and embedded systems. The tone is full and loud.

It does not use any medium or large-scale integrated circuits, and the op amps and logic chips used are very old antiques (such as uA741, LM124, 74LS/54LS, etc.).

The circuit adopts a multiplex electronic music design and is mainly divided into timing controller, vibrato oscillator, sound source VCO oscillator, bandpass filter, envelope generator, multiplier, mixer, preamplifier, power supply, etc.. ....

The digital part takes the 74LS164 shift register as the core and uses the loop method to encode the music.

The vibrato generator part takes the VCO of 74HC4046 as the core and uses voltage control to FM modulate the output frequency to achieve the FM music effect. The vibrato oscillator frequency is between 3.5-3.9Hz.

The power supply part may consider adding an active temperature control system.

At present, the project has no physical objects and is under development.

Due to logistics disruptions at the main developer's office (BH2VGM), the project has been severely delayed and is expected to be completed before April 24, 2023 (the 53rd anniversary of the launch of the Dongfanghong-1 satellite). (Book dated April 15, 2022)

The project members cover a wide range of projects and all play a key role in the project. The list of members below is being compiled. At the same time, like-minded people are welcome to join the research.

At present, the digital part has completed simulation and physical testing, but there are still some problems with the power part. Multiplier replacement is in the works, attenuator part not yet tested (June 25, 2022 book)

Simplified simulation of the digital main control part:

The digital part is physical:

Current (June 25, 2022) progress: 80% of the hardware has been completed, and coordination has not yet started