Basic electrics are possible as soon as you have decent metalworking. Dynamos are just a bunch of spools of copper wires and magnets. Add some graphite, and you have telephones. Greeks could have made them.
Wire making is easy if you have copper. The real problem is insulating the wire, especially with something flexible enough for winding coils. This is part of the problem of infrastructure—and very few people know enough to really even start working on a serious rebuilding problem, for example after a dinosaur killer impact. I know more than anyone else I have ever met, especially in the areas of food (agriculture and cooking) and shelter (designing, concrete, masonry, carpentry, plumbing, wiring, etc), and even I barely know enough to get started. For example, I don’t know of any way to make insulation for wires without an already existing chemical industry, except natural rubber, which would most likely not be available.
If you look closer, you’ll probably find only the outer protective layers are cloth; I’ve seen that on a lot of older wiring, but the ones I have seen all had a thin inner layer of rubber right on the copper. Tarred cloth probably would work, as long as the voltages were low enough and there were multiple layers; paper might be even better though. (Most of the old wiring I have seen was a thin layer of rubber next to the copper, then paper wrapping protecting the rubber and separating the individual wires, and the whole bundle protected with fabric.)
Wrap cloth around it, or coil a single thread around it, then coat with tar. Lots of organics will turn to “tar” if abused properly, even cooking oils. Also, steel will do instead of copper, you just need a few times a much of it.
On the other hand, is any of this really necessary ? If this civilization collapses, there’ll be enough ready-made materials lying around to last for a thousand years.
Wind each layer sparsely so that wires don’t touch and pack insulator (dried leaves) between the layers. Makes for a woefully inefficient spool, but still.
That would probably work, the only problem with it is that you would have to know in advance what you were doing, this isn’t something that would be tried by an experimenter trying to figure things out for example.
I don’t know, but even if they could do it, they had no reason to. So we can’t really tell.
The real question is—if they really really wanted to and had a book of helpful tips, could they have made decent enough wire? (And could they get copper in sufficient quantities? By Roman times they certainly could.)
Basic electrics are possible as soon as you have decent metalworking. Dynamos are just a bunch of spools of copper wires and magnets. Add some graphite, and you have telephones.
Greeks could have made them.A printing press should be easier to make...
Wire making is easy if you have copper. The real problem is insulating the wire, especially with something flexible enough for winding coils. This is part of the problem of infrastructure—and very few people know enough to really even start working on a serious rebuilding problem, for example after a dinosaur killer impact. I know more than anyone else I have ever met, especially in the areas of food (agriculture and cooking) and shelter (designing, concrete, masonry, carpentry, plumbing, wiring, etc), and even I barely know enough to get started. For example, I don’t know of any way to make insulation for wires without an already existing chemical industry, except natural rubber, which would most likely not be available.
I’ve seen cloth-wrapped appliance cords—never tried it, but it might be feasible.
If you look closer, you’ll probably find only the outer protective layers are cloth; I’ve seen that on a lot of older wiring, but the ones I have seen all had a thin inner layer of rubber right on the copper. Tarred cloth probably would work, as long as the voltages were low enough and there were multiple layers; paper might be even better though. (Most of the old wiring I have seen was a thin layer of rubber next to the copper, then paper wrapping protecting the rubber and separating the individual wires, and the whole bundle protected with fabric.)
I think I solved the insulation problem. Cockroach bodies should work if you can gather enough.
Wrap cloth around it, or coil a single thread around it, then coat with tar. Lots of organics will turn to “tar” if abused properly, even cooking oils. Also, steel will do instead of copper, you just need a few times a much of it.
On the other hand, is any of this really necessary ? If this civilization collapses, there’ll be enough ready-made materials lying around to last for a thousand years.
Wind each layer sparsely so that wires don’t touch and pack insulator (dried leaves) between the layers. Makes for a woefully inefficient spool, but still.
Gotta try this out with scrap metal.
That would probably work, the only problem with it is that you would have to know in advance what you were doing, this isn’t something that would be tried by an experimenter trying to figure things out for example.
Hence the book.
Well, did the Greeks have the ability to make decent enough wire in sufficient quantities?
I think they could. Remember the Antikythera mechanism’s high quality of fabrication. And fine metal wire was useful for jewelry and art:
http://store.metmuseum.org/Bracelets/Greek-Filigree-Wire-Bangle/invt/09085051
http://phoenicia.org/dentstry.html
http://www.wireworkscustomjewelry.com/history-of-wire-art-jewelry/
I don’t know, but even if they could do it, they had no reason to. So we can’t really tell.
The real question is—if they really really wanted to and had a book of helpful tips, could they have made decent enough wire? (And could they get copper in sufficient quantities? By Roman times they certainly could.)
Could they make it thin enough (even with insulation) to be able to fit large amounts of windings?
ie, assuming they had reason to try, could they do it based on what we know of their capabilities at the time?
Incidentally, a radio would be much cheaper to make and almost certainly within their capabilities.
Yes.