The driver board assembly progressed nicely. I had to stop soldering until the correct R23 and R3 resistors arrive. If I go further, I won’t be able to get to them.
I also ordered the heat sink assembly kit for the MOSFETS. You can see below that the heat sinks are attached but the MOSFETS are not soldered in. When the kit arrives, I will attach the MOSFET to the heat sink and solder it to the board at the correct height.
The mounting kit contains a shoulder washer, screw, nut, and a Mica insulating pad.
I had a couple challenges today. I put the 100K trimmer pots on the wrong side of the board. I discovered this while searching for the U1 and U2 pads. I discovered both components go on the bottom of the board. Tom neglected to put that detail in the instructions.
The reason is simple. The back side of the board faces up. This is the side with the valve sockets. One will want access to the trimmers for biasing.
The problem was easily corrected by my solder sucker.