This board already has 2x10nF capacitors fitted between pins 2&3 of MAS1 and MAS2(as shown in solder side photo
This modifications separate the 0V supply for the dimmed outputs from the 0V
supply which is fed from the 10way IDC connector.
1. Cut track near 0V supply cable on component side of
2. Remove capacitor BY4.
3. Cut two tracks on solder side of
4. Scrape the surface of the 0V plane and add
twox16x0.2mm link wires (twisted together) from 0V supply to 0V plane.
5. Solder the supply cables (yellow and black) as shown in top photo.
Note that the 0V supply cable is on the pad directly above the wire link.