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7. ... a "cooling jacket for a low noise amp". So there's a big yellow metal tank like an oxygen tank connected to it, so I'm assuming that it's liquid nitrogen? Yes? No? Do they use liquid nitrogen for that? The kid writes his name with his fingertip in the frost on the canister-thingie, which looks like it's made of Pyrex like a beaker. Is that plausible, that a "cooling jacket" with liquid nitrogen would be made out of Pyrex? Also, wouldn't the kid's fingertip freeze?
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The key element needed to be chilled in a low-noise receiver is not an amp on a shelf somewhere, but the actual detector, located at the focus of the telescope dish. In the FM band, though, there's no real need for even that, as it's far from the microwave frequencies produced by thermal radiation.
The kid's fingertip would probably be ok after a brief touch to the outside of a container of LN2, especially if it was at least minimally insulated. The frost demonstrates that it's not very well insulated, but he might get away with it.
He'd regret it if he dunked his pinkie, though.
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Actually thats not necessarily true - I have put my finger in Liquid Nitrogen before. Obviously not for a long time but you can dip it in and out quickly. Because your hand is so hot (above the boiling temp for N2) it turns the nitrogen around it into gas and creates an insulating layer. This obviously doesn't work for long before the cold gets through anyway. But it was kinda cool. NB - if you ever try it - don't leave your finger in there!!!