Balanced Modulator MC1556G (CB14559E)

We found this circuit in Motorola's Linear Databook in 1990. The semiconductor component used is no longer common today.

LC Oscillator Using the 4069 (CIR093E)
Here we show an oscillator that uses an LC network. The upper limit depends on the power-supply...
DVM to PC adapter (CB7924E)
This circuit from a Popular Electronics from the 90s allows you to use an old PC as a digital...
DC Amplifier with Drift Compensation (CB14068E)
of the National Semiconductor of 1994. The same technique can be used with other operators and the...