Maybe closing in on room temp superconductors:

Originally posted by sonhouse
http://phys.org/news/2015-02-world-superconductors.html

I have read it and doesn't look too hopeful to me. They haven't even proved it definitely superconducts at 100k -only an experimental result that shows it might do. And that doesn't beat the would record which is, if I remember correctly, about 150k (can anyone say exactly what it is? )
Still, I am sure one day someone will make the kind of breakthrough we all want to hear.

Originally posted by humy
I have read it and doesn't look too hopeful to me. They haven't even proved it definitely superconducts at 100k -only an experimental result that shows it might do. And that doesn't beat the would record which is, if I remember correctly, about 150k (can anyone say exactly what it is? )
Still, I am sure one day someone will make the kind of breakthrough we all want to hear.

134 K comes to mind. But the thing about this result is it is a completely different approach. Maybe that is what is needed to spur further progress.

The latest high temp ones work at LN2 temperature. I wanted to see how well superconductors would work as an RF antenna. I thought if the Q of the circuit is Impedence/resistance, if resistance goes to zero, Q would go up really high, which I thought would be useful for receivers by limiting sideband interference before it gets to the receiver. So with that in mind, I called up American Superconductor, Inc. and asked if I could buy some superconductive wire.

I figured I could use polyflow tubing with a nice layer of insulation around it and the antenna wire inside then hooked to copper to get to the receiver.

They said, 'not interesting enough experiment' and shut me down. Refused to do business with them.

I wasn't asking for a gift, I was willing to pay for it but they didn't want to deal with a mere amateur radio experiment.

I was thinking superconducting parabolic reflectors might give some benefits also but have not seen any work in this area.

Can you imagine a superconducting parabolic RF reflector, like a radio telescope? If it had some beneficial effect, it would probably cost the national budget to make🙂

Unless you can get the stuff to work at room temperature.

Originally posted by sonhouse
134 K comes to mind. But the thing about this result is it is a completely different approach. Maybe that is what is needed to spur further progress.

yes, hopefully.

I got the ~150k figure by looking at the "superconductor time line" graph at:
http://en.wikipedia.org/wiki/High-temperature_superconductivity#mediaviewer/File😕c_history.gif

Originally posted by humy
yes, maybe.

I got the ~150k figure by looking at:
http://en.wikipedia.org/wiki/High-temperature_superconductivity#mediaviewer/File😕c_history.gif

I got the temp of LN2, comes in at 77 degrees Kelvin. So anything above that and you have a nice superconductor.