SRA555 -

sr555The SR554 is a low-noise, transformer-coupled preamplifier optimized for source impedances between 0.05 Ω and 1 kΩ. With an input noise of only 0.1 nV√Hz, the SR554 can be used in aSR555 ... $1095 (U.S. list) k with SRS lock-in amplifiers. Current amplifiers provide gain close to the experimental detector, allowing the user to minimize input cable length and its c