The wires that leave that board and connect to the 4 pin socket aren't connected to the correct places on that filament board (they do not connect to the DC pads on the front side of the board, those should be left empty).
To the naked eye, I do not believe you have the correct resistor values in the R1 and R2 holes on this PC board. It is extremely important to double check resistor values with your meter if you aren't 100% sure that the colors are correct, or if they are too hard to see. I think (at minimum) that they are switched in the place where I am looking, but the 1K resistor I see has some unexpected colors, so this needs to be double checked.
If you have 1-2V coming off the front pads on that PC board, then I'd want to see what the soldering looks like on the bottom of the board, as it should be more like 8V (especially if there are no 300Bs plugged in).
