Did I discover a manual error in the schematics?
The schematics say that the channel 1 position of the mode select should be 1100 for the last 4. The first one on the left is just power and is ignored in this part of the schematic.
However, when I look at my scope, it is 1001.
1 signifies a closed contact and a 0 is open.
Channel 2 mode position shows 1010 in the schematics, but also see 1010.
Is this a schematic error? Or is something very very wrong?
The rest of the positions follow the schematic fine. It's only the CH1 position that is off.
My scope also seems to have a low serial number, but SW300 is not marked as having been modified at higher serial numbers.
Channel 1 and 2 modes work fine. When channel 1 is on though the beam is brighter than usual. I can tell because I can see the sweep reset at full intensity. This was not an issue before. This only happens with ch1. CH2 seems to work fine except that ch1 position control has a mild effect on ch2's.
Alt and chop are very broken, likely because of that faulty 7472 chip. It'll arrive tomorrow so I can check then. CH1-CH2 works perfectly.