So, for anyone wondering how they're planning to transmit a signal without electronics -- well, given that they are using high-temperature electronics to some extent, they might just go that route. But the article I linked above does mention a proposed mechanical means: You don't actively transmit a signal, rather you just change some visible feature of the rover and have a conventional-electronics orbiter scan for and detect these changes (so, signal isn't emitted from the surface of Venus, just reflected from there).
They could also use one of the techniques used by the NSA, selectively ground a Quarter wave antenna in a corner reflector N times a second... then transmit a signal at the resonant frequency at said reflector, listen for a hetrodyne N hz off the transmitted signal.
Very little power is required to ground a wire, or not.
"By contacting former Soviet scientists, he obtained raw data from the [Soviet Venera] missions, processing it himself to produce fantastic pictures, which are now available on his website:"
There exist magnetic core materials with Curie points above the temperatures on Venus, there exist insulators and conductors effective at those temperatures as well.
Thus it should be possible to build some form of magnetic logic CPU that could operate in that environment provided a suitable power supply.
There are obviously chemical-based processes for recording photos and video. They can be adapted for high temp. Balloons can be used to lift those records and other data high into the atmosphere, where temperatures are lower and they can be recovered and converted to electronic data by more conventional vehicles. It's very, very difficult, but not impossible.
They specifically mention the issues with an RTG in the article. The high surface temperatures make radiating the excess heat off very hard. Same holds true for any sort of peltier chamber or heat-pump.
Hard, but not impossible. TEG modules are available with the hot side operating at 800C, so I'm sure TEC modules can also be built with hot sides well above ambient on Venus.
Cool idea but it seems a tad more practical to use conventions electronics in a well isolated and temperature controlled bubble. In steampunk spirit, why my a low flying airship? Wind speed is apparently very low near the surface.
Without active cooling your box will equalise to that temp. And building a heat pump that can cool the inside of a box to <100C when ambient is >450C is... an interesting project.
You may as well just build a mechanical computer using gears and such. Modern manufacturing would make it practical to build a wind-powered tiny geared mechanical CPU and memory.
Thermal expansion would be a challenge, but not an impossible one.
Peripherals would still be a problem. Receiving commands would likely be impossible, so it would have to be autonomous. But you might be able to use a chemical/optical system for signalling. Or maybe vary radar reflectivity. Or...?
We use colder then ambient heat pumps all the time - that's just air conditioning. Provided you heat your hot side to hotter then ambient, you can move heat around.
The problem with Venus is that "hotter then ambient" is already melting lead and significantly derating most other materials. We're talking an incredible amount of energy and mechanical parts (it's a heat pump) to do it.
I would be curious if there's any possible Peltier design which might be able to keep up.
Not just that, you also need a power source. An RTG where the cold parts are 470C isn’t going to be efficient so now you need to dissipate a lot of heat to provide any power.
Overall, powering the electronics in a sealed box with a battery and a short supply of cryogenic coolant seems like the only viable option. However, even a few hours would be difficult.
The issue isn’t willingness it’s a concern about power output. But, sure if you scale the wind turbine large enough and had some form of energy storage that should be possible even if it’s not actually viable.
And here's an earlier article about the approach of using high temperature electronics instead -- although note that, as described in the OP, the two approachese seem to have now merged: https://www.sciencemag.org/news/2017/11/armed-tough-computer...
So, for anyone wondering how they're planning to transmit a signal without electronics -- well, given that they are using high-temperature electronics to some extent, they might just go that route. But the article I linked above does mention a proposed mechanical means: You don't actively transmit a signal, rather you just change some visible feature of the rover and have a conventional-electronics orbiter scan for and detect these changes (so, signal isn't emitted from the surface of Venus, just reflected from there).