There are many schemes on inexpensive hardware components. Power supplies, converters and all that.
1. Scheme charger rechargeable flashlight (dangerous for the battery)

2. The voltage regulator on FRI

3. The constant current sources

4. The current source

5. A voltage regulator

6. The current source

7. A bipolar current source

8. The constant current sources

9. Charger

10. A voltage Converter

11. Very good charger

12. The option of replacing the high-voltage Zener diode

13. A simple indicator of radiation hazard

14. Charger

15. A voltage Converter

16. The constant current source

17. The analogue of the Zener diode

18. A voltage regulator with current limiting - current source

19. A voltage regulator for battery charger solar battery

20.Compensation of fluctuations in the power supply

21. The charger is powered by free energy

22. The voltage regulator on the logical element

23. A simple constant current source

24. Switching regulator condenser BP

25. Transformerless power source hours on the optocouplers

26. Structural diagram of the capacitor voltage Converter with a multiplying current
27.Capacitive voltage Converter

28.The current source integrated Zener diode

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