some old designs i've built some years ago using the cheaper DIP versions of the matched BJT pairs from Analog Devices.
Designs are DC-coupled, gain 1000 as they were designed for measuring the noise of photodetectors.
Given values are not 100% what i've used later, only for drawing the schmatics (e.g. gain setting resistors or compensation), but order of magnitude is right.
Eagle-files + Documentation:







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