Apollo Gyro Display Coupler
The Apollo command module (CM) has about 20 or so large boxy electrical modules similar to this. They are marvelous in their design, driven not by aesthetics but by size and weight limits.
Consider the engineers who designed this unit and those who created and managed the construction and testing of each of these. And then do that another 20 to 30 times. And then multiply that for each of the other boxy things such as the VHF radio, MDM and so on.
This is called the “Gyro Display Coupler” and was the unit that helped keep the crew informed of their actual attitude. This would be compared to those generated by Inertial Measurement Unit that would give the calculated attitude that.
When struck by lighting during its launch, Command Module Pilot, Dick Gorden can be heard saying “ All we've got's the GDC.” Meaning that main attitude module was knocked offline so they had to rely on the backup.
