On Sat, 01 Nov 2014 18:47:32 -0400, rickman wrote:
I think you are confusing need with practicality. There is nothing to
stop you from making a superconducting antenna. There just isn't a need
for it unless you live in Gareth's world. Hmmm... wasn't that a movie?
Gareth's World?
(...)
I believe there are rather cold temperatures in space. A
superconducting antenna could be used there with *no* supporting
"apparatus".
You don't need to go to outer space to see cryogenic radios in
operation.
Superconducting radio frequency
http://en.wikipedia.org/wiki/Superconducting_radio_frequency
In a past project, I worked with cryogenic duplexers and receiver
front ends for cellular service. My part had nothing to do with the
superconducting components, but I got to watch them perform. Filters
with nearly vertical skirts, sky high filter shape factors, zero loss,
near zero noise figu
http://www.suptech.com/wireless_overview_n.php
http://www.suptech.com/pdf_products/cryogenic_receiver_front_end.pdf
http://www.suptech.com/pdf_products/SuperLink_850_G3AB.pdf
Where cryogenic front ends worked best are in installation without
towers, where the coax cable losses were less, and the cryo unit can
be located in a nearby rooftop shelter. These tend to be located in
urban jungles, where signals are traditionally weak, and handset
density rather high.
At the same time, TMA (tower mounted amp) technology appeared, which
provided many of the benefits of cryogenic receiver front ends, but
without the complexity, power consumption, and cost of the cooling
components:
http://en.wikipedia.org/wiki/Tower_Mounted_Amplifier
https://www.google.com/search?q=tower+mounted+amplifier&tbm=isch
http://www.commscope.com/catalog/wireless/2147486004/product.aspx?id=162&sortExp=Name&nrp=100
Also, note that spacecraft all have some form of temperature control
where the electronics do NOT operate at cryogenic temperatures:
http://en.wikipedia.org/wiki/Spacecraft_thermal_control
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558