Clock alarm timer (CB21290E)

Found in Popular Electronics from the 90's, this circuit uses common components and can be easily implemented.

| Clique na imagem para ampliar |

Battery Charger (CB4388E)
This circuit, obtained from a 1965 magazine, can still be assembled using some modern equivalent...
Ramp generator with the 555 (CB7598E)
We found this circuit on an Elektor from the 90s. The frequency is given by capacitor C1. The...
5 V x 10A power supply (CB15926E)
This powerful regulator, shown in the figure is for 5V (TTL) is suggested by Motorola and makes use...