This circuit was found in a Popular Electronics from the 90s. The circuit has temperature compensation. Coil and capacitors depend on the frequency at which the circuit will be used.
We found this circuit in an American documentation from the 60's. The transistors are made of...
The accuracy of this circuit depends on adjustments made with capacitors of small tolerances of known...
The figure shows how to implement an OR function with two inputs, using a relay. The relay...