Low noise amplifier (T466E)

Found in 1948 MIT documentation, this 4-tube amplifier is characterized by its low noise level.

T Bridge Audio Oscillator (CB4689E)
This circuit is from an ancient American documentation. The T-Bridge circuit determines the...
Auto Bias for FET (CB6125E)
This configuration is from a 1964 US documentation valid for any FET. The range of power voltages...
Differential instrumentation amplifier (CB9841E)
This instrumentation amplifier with differential inputs was found in documentation from the 90s....