In this circuit, obtained from a 1979 publication, IC1 is a 555 and IC2 is a 4020. The transistor is the BC548. The supply voltage of 6 or 12 V depends on the relay used. The diodes can be 1N4148 or 1N4002 and the time adjustment must be done in RV1. Capacitors C1 and C2 must be of excellent quality.
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