SC522 is a modular backplane designed for Z50Bus.
Experienced builders can just go ahead and populate the board. There shouldn’t be any surprises to catch you out.
This guide assumes you are familiar with assembling circuit boards, soldering, and cleaning. If not, it is recommended you read some of the guides on the internet before continuing.
First check you have all the required components, as listed in the parts list.
Before assembling it is worth visually inspecting the circuit board for anything that looks out of place, such as mechanical damage or apparent manufacturing defects.
The picture below shows what a completed SC522 Modular Backplane should look like.

Male bus header
Fit and solder the Z50Bus male bus header pins, P1 (shown below in red).
This fits over the edge of the PCB as illustrated above.

A good strategy for fixing this so the pins are parallel to the circuit board is to solder one pin near each end, on one side of the board. Check the pins are parallel and adjust if necessary. Now solder a similar pair of pins on the other side, and again adjust as necessary. Now solder a few on each side, then swap sides until all the pins are soldered.

Expansion socket
Fit and solder the female header.
This fits over the edge of the PCB as illustrated above.


Card sockets
Fit and solder the Z50Bus sockets.


Inspection
Remove any solder ‘splats’ with a brush, such as an old toothbrush.
Visually inspect the soldering for dry joints and shorts.
Clean the flux off with suitable cleaning materials.
Visually inspect again.
If all is well, go ahead and give it a try.
The SC22 User Guide can be found here.