This circuit oscillates in the fifth harmonic of the crystal frequency. The circuit is from a 90's documentation. L1 must be according to the desired frequency.
This circuit is from a 1975 Miniwatts magazine, therefore using Philips components from that time,...
This interesting transistor circuit has several effects and an included amplifier. The circuit is...
This circuit, suggested by Philips Components, uses as a base a voltage comparator of the type...