This high-speed circuit was found in 1980s Linear Technology documentation. The circuit makes use of components of the time with TTL output and TTL input that enable their use as a shield.
This is the circuit of a sensitive voltmeter using a difficult-to-obtain 5 uA full-scale...
The circuit is from the United States Hands-On Electronics magazine, February 1987 edition. The...
The circuit shown was suggested by Analog Devices (www.analog.com) in its Application Note AN-411...