I’ll be playing with high-voltage power tomorrow. Can’t imagine anything going wrong with that!

LOG ENTRY: SOL 193

I managed to not kill myself today, even though I was working with high voltage. Well, it’s not as exciting as all that. I disconnected the line first.

As instructed, I turned a rover charging cable into a drill power source. Getting the voltage right was a simple matter of adding resistors, which my electronics kit has in abundance.

I had to make my own nine-amp breaker. I strung three three-amp breakers in parallel. There’s no way for nine amps to get through that without tripping all three in rapid succession.

Then I had to rewire a drill. Pretty much the same thing I did with Pathfinder. Take out the battery and replace it with a power line from the Hab. But this time it was a lot easier.

Pathfinder was too big to fit through any of my airlocks, so I had to do all the rewiring outside. Ever done electronics while wearing a space suit? Pain in the ass. I even had to make a workbench out of MAV landing struts, remember?

Anyway, the drill fit in the airlock easily. It’s only a meter tall, and shaped like a jackhammer. We did our rock sampling standing up, like Apollo astronauts.

Also, unlike my Pathfinder hatchet job, I had the full schematics of the drill. I removed the battery and attached a power line where it used to be. Then, taking the drill and its new cord outside, I connected it to the modified rover charger and fired it up.

Worked like a charm! The drill whirled away with happy abandon. Somehow, I had managed to do everything right the first try. Deep down, I thought I’d fry the drill for sure.

It wasn’t even midday yet. I figured why not get a jump on drilling?

[10:07] Watney: Power line modifications complete. Hooked it up to a drill, and it works great. Plenty of daylight left. Send me a description of that hole you want me to cut.

[10:25] JPL: Glad to hear it. Starting on the cut sounds great. Just to be clear, these are modifications to Rover 1, which we’ve been calling “the trailer.” Rover 2 (the one with your modifications for the trip to Pathfinder) should remain as is for now.

You’ll be taking a chunk out of the roof, just in front of the airlock in the rear of the vehicle. The hole needs to be at least 2.5 m long and the full 2 m width of the pressure vessel.

Before any cuts, draw the shape on the trailer, and position the trailer where Pathfinder’s camera can see it. We’ll let you know if you got it right.

[10:43] Watney: Roger. Take a pic at 11:30, if you haven’t heard from me by then.

The rovers are made to interlock so one can tow the other. That way you can rescue your crewmates if all hell breaks loose. For that same reason, rovers can share air via hoses you connect between them. That little feature will let me share atmosphere with the trailer on my long drive.