"Forgotten" technologies
Aug. 3rd, 2020 10:03 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
kengrFor folks writing or gaming in situations where people might encounter long forgotten (or hidden) installations there are several technological bits that would make fun additions.
First off, our old friend TIMMs. Thermally Integrated Micro Modules.
These were blocks of ceramic and high temp metals. They were developed after EMP was discovered as something that could survive EMP bit still not be much bigger than the then current gear that used printed circuits with individual transistors and the like.
They were tube based, but the tube were the size of a dime. and the units were a solid block of metal and ceramic except for the cavities that were the vacuum inside the tubes or the filling of capacitors.
The didn't have filaments for the tubes, so that eliminated one common source of failure in tube based equipment. Instead the blocks were placed in what amounted to a well insulated oven and heated to a dull red heat which got the cathodes hot enough to work.
These would be great for gear in the stereotypical volcano lair or around a big nuclear reactor.
Next, if you encounter a *really* old installation (say 1890s to 1920s) you may encounter radio transmitters (morse code only, not voice) that don't use tubes. Instead they use an alternator (a sort of AC generator) to generate the signal.
Another fun thing are radon bulbs. Used for emergency lighting, they are glass globes or other shape, The inside is coated with a phosphor much like the ones used in fluorescent lights. They are filled with radon gas, and the particles emitted by the decaying radon strike the phosphor coat and produce light.
You could probably make some something similar with other radioisotopes, but radon is what was used in the ones I've read about.
"Gee, how are these lights still working? They're a bit dim, but..."
"Wait a sec. Look at how they are mounted. There aren't any wires..."
Just the thing to creep out the radiation averse. :-)
(added later)
Oh yeah, refrigeration gear. Before freon was invented commercial refrigeration used 3 different easily liquified gases as working fluid: Chlorine, ammonia and sulfur dioxide.
all of these are toxic. and they meant leaks were a *really* bad thing. Which is why home refrigeration didn't take off until freon came along.
Note that they are *still* used to some extent in commercial plants.
First off, our old friend TIMMs. Thermally Integrated Micro Modules.
These were blocks of ceramic and high temp metals. They were developed after EMP was discovered as something that could survive EMP bit still not be much bigger than the then current gear that used printed circuits with individual transistors and the like.
They were tube based, but the tube were the size of a dime. and the units were a solid block of metal and ceramic except for the cavities that were the vacuum inside the tubes or the filling of capacitors.
The didn't have filaments for the tubes, so that eliminated one common source of failure in tube based equipment. Instead the blocks were placed in what amounted to a well insulated oven and heated to a dull red heat which got the cathodes hot enough to work.
These would be great for gear in the stereotypical volcano lair or around a big nuclear reactor.
Next, if you encounter a *really* old installation (say 1890s to 1920s) you may encounter radio transmitters (morse code only, not voice) that don't use tubes. Instead they use an alternator (a sort of AC generator) to generate the signal.
Another fun thing are radon bulbs. Used for emergency lighting, they are glass globes or other shape, The inside is coated with a phosphor much like the ones used in fluorescent lights. They are filled with radon gas, and the particles emitted by the decaying radon strike the phosphor coat and produce light.
You could probably make some something similar with other radioisotopes, but radon is what was used in the ones I've read about.
"Gee, how are these lights still working? They're a bit dim, but..."
"Wait a sec. Look at how they are mounted. There aren't any wires..."
Just the thing to creep out the radiation averse. :-)
(added later)
Oh yeah, refrigeration gear. Before freon was invented commercial refrigeration used 3 different easily liquified gases as working fluid: Chlorine, ammonia and sulfur dioxide.
all of these are toxic. and they meant leaks were a *really* bad thing. Which is why home refrigeration didn't take off until freon came along.
Note that they are *still* used to some extent in commercial plants.
no subject
Date: 2020-08-04 02:50 pm (UTC)Part of the problem with making a forever light is that very few radioactive materials glow on their own, so they need phosphors. Most of those currently used - even with phosphors - have short half-lives (for example, the half life of radium-226 is around 1,600 years; tritium is around a piddling 12 years). So you need a durable, probably non-crystalline phosphor efficient for the type of radiation the source gives off. It can be done. There is actually a lot of reference material out there for self-luminous signs. However, those are only rated in years and not millennia. Something lasting thousands of years would likely require quite a bit of materials research, if only to make sure nothing dangerous is likely to escape.
As for working while red hot, for really hot operating conditions you probably want ceramics. Adolph Coors, besides making beer, have long had a business of making laboratory-grade ceramics. Back in the late-Fifties to early-Sixties they were involved in a project to produce a half-gigawatt, air-cooled fission reactor. They developed pneumatically-operated, ceramic actuators designed to operated while white hot. The government reactor project was cancelled before completion, but today the descendants of those actuators are still used in some steel mills.
Which gives me the mental image of fluidic circuits in ceramic media operating somewhere very hot.
no subject
Date: 2020-08-04 05:02 pm (UTC)At that point you need something like an electroluminescent panel powered by some sort of RTG or the like. That way you have a much bigger ratio of radioactives to light source.
TIMMs do use high temp ceramics. They also used a 3D parts layout. So you had this brick of ceramic and high temp metals with contacts on the surface.
Very much "solid state" circuitry. :-)
Reminds me of the discussions on the TML (Traveller Mailing List) about players finding derelict spacecraft. If they are *old* (centuries, rather than decades), you start running into "interesting" problems.
Due to diffusion of atoms, you get vacuum welding of things in contact. Even if the vacuum isn't that good. You also get semiconductor based devices that no longer work because the dopants have migrated across the PN junctions.
The higher the level of integration (more parts per square micron) the faster they'll go bad. Same is true of a lot of SF standbys such as "molecular circuitry". I wouldn't bet on *any* nano-scale tech surviving.
Damage from cosmic rays and the like are another factor.