Attitude Directional Indicator: First steps...

Hey! This time I desired to investigate an analog ADI unit used in a former 737. (See the video at the end !!)

The Unit...

Brand: Collins

PN: 787-6892-003

The device is a mixture of digital and analog electronics, so tat means that expects synchro transmitters signals and simple analog signals.

The insights....

Here we can see an overview of the mechanics parts:

This is the electronics section that is composed by 5 controller boards and 2 power supply boards attached in the back cover.

Mechanics from the top:

A closeup of the flight directo gears:

Some more pictures:

The test bench...

For this first test related with the Gyro inputs, I'm just powering up the unit with 26Vac 400Hz and connecting two synchros to emulate the Pitch and Roll signals.

A video about how this is working: