Modulator Amplifier (V1574E)

This circuit is from a 1938 tube manual. Transformers are the critical components. Component values are given.

4 and a half digits display with ICL7135 (CB15361E)
This circuit is from the 1983 Intersil Databook. In it we have the use of the ICL7135 as an AD...
Crystal Calibrator (CB21783E)
This circuit generates a 1 MHz signal for general equipment calibration. The circuit is from an...
Positive Edge Differentiator (CB13217E)
We found this circuit in a Motorola publication from the 70s. The circuit can be implemented with...