I’ve just finished building a DIY Cadet II RGB encoder, and my build doesn’t currently work correctly. I have a V1.1 board that I bought a week ago. I started checking voltages, and found the +5V output from the 7805 was no good (~1.2V). Then I traced all my soldering, and found that the common (ground) pin on the 7805 wasn’t connected to ground on the euro power connector. I couldn’t see any issue with my soldering, so I referred to the (hi-res) photos I took of the board before soldering it, and I can’t find any connection between the euro power connector ground (pins 3 through 8) and the main ground net on the board! Is this expected?
I looked at the schematic and the +5V regulation section is a bit different to what I’m used to seeing - the 7805 has some small capacitors next to it (presumably internal to the 7805 part and just there for information?) and a little ground icon connected to the pins common to those two little capacitors, which looks like it is then connected to the main ground plane.