We stay overnight at our usual Alice Springs accommodation, the Macdonnell Ranges caravan park.
In the morning, I try to re-solder a bypass diode on the rear array. My gas iron won't light -- I suspect that the fitting on the refill can is wrong and I'm just not getting any gas into it. I try my 240V iron, running off an inverter plugged into a cigarette lighter. It doesn't get hot enough -- I think it doesn't like the inverter's output, which is not true sine wave. On my third attempt, I get an iron that works.
We spend several hours charging. I try to get some telemetry numbers, but I am unable to even flip the coin: the Bluetooth receiver dongle for the laptop has gotten crushed, and is broken: Windows doesn't even notice when I plug it in. I try to repair it, and succeed to the extent that when I plug it in, Windows now recognises it as an invalid device.
We go in to town to buy a replacement. On the way, we notice that one of the back streets that the route notes instruct solar teams to use to get to the control point is closed by the council: they're resurfacing it. Solar teams trying to find it will have to detour, in a strange town, with no map, and no signage.
Sure enough in town we see a solar car, lost.
We buy a Bluetooth dongle at Jaycar and return to the control point to serve the remaining 12 minutes. Then we trailer 60km out of town to the next long downhill run, and begin solaring. Telemetry works, albeit with reduced range.
We solar most of the day, with a break for lunch and charging, and end 12km short of the next control point, Kulgera. Into the trailer and trailer forward the remaining 12 km, and we get in at 11 minutes to 5. This is only a 10 minute stop, so at 4:59pm we're free to go. We elect not to solar onwards for the remaining one minute of the day, so we charge and camp. We've solared 187 km for the day.
I repair the bluetooth dongle with a single strand of wire taken from a larger piece of multi-stranded wire, soldered onto a quarter-millimetre wide solder pad scraped carefully clean of its protective coating with a craft knife.
We charge, and I get in the solar car to drive it out of Kulgera. I turn the "go" knob. Nothing happens.
I turn it again, just in case. Still nothing.
I turn the motor controller off and on again, and try again. Not a sausage.
We pull the lid off and ponder the wires. Trent notices that the brake lights are on: the motor controller refuses to allow you throttle up while your foot is on the brake. But the brake lights are on even when my foot is off the brake pedal. The switch that is supposed to tell when the driver's foot is on the brake has come loose, and is confused. John wraps it in tape, thus persuading it that my foot is not on the pedal, and we begin solaring.
Again we solar steadily then pause for lunch and charge.
As we take the rear array off to charge, the telemetry antenna breaks off. I swap in the antenna from the follow vehicle, and in the follow vehicle I switch back to using the antenna-less, reduced-range Bluetooth dongle.
We solar some more. The tape we wrapped the brake switch in lets go and the car rolls to a halt. So we cut the wires to the switch.
A little short of Cadney homestead, we put the car in the trailer and trailer forward to the Coober Pedy control point. We have solared 213 km for the day.
Our stay in Coober Pedy is much like our last two challenges: accommodation at the underground backpackers', dinner at the pizza shop, concluding with making sculptures with the detritus of the meal.
-- Doug Burbidge http://dougburbidge.com/