Tibor's notebook - volume 2 - Transistor timer circuit

This is Tibor's second notebook on which he started working back at home. The work shown originated in the time between christmas and exam preparations. It is about reconstructing the electronic timer circuit for the rope pump's magnets, using only transistors instead of integrated circuits. This is not only for cost and availability reasons (in the new design, *any* type of small NPN transistor from scrap etc. should work), but also because those three-legged transistors allow more accessible ways of assembling the circuit, going without circuit boards and maybe even without soldering.