Quote:
Originally Posted by kalee20
Quote:
Originally Posted by Craig Sawyers
Most active electronics keels over at low temperatures (nitrogen and below).
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Yes - you'll note that I advocated LHe cooling the preamp resistors only |
Still doesn't work. Most metal film resistors us a NiCr film. Nichrome has the following resistance for 32AWG wire:
32C (305K) - 34 ohm/m
77K (LN2) - 33.4 ohm/m
4.2K (LHe) - 33.2 ohm/m
Since the resistance of NiCr stays pretty much constant all the way down to 4.2K you get absolutely no noise benefit from cooling the resistors.
Craig