Geiger Counter (CB21199E)

Found in old documentation, this meter has a high voltage inverter for the Geiger tube. The circuit provides signals to a headset.

| Clique na imagem para ampliar |

12 V x 2 A switched regulator (CB8707E)
Found in 1965 Delco Radio documentation, this circuit uses transistors from that era. Modern...
1 Minute to 20 Hour Timer (CB12118E)
This circuit was obtained in a 1979 publication but can still be easily assembled today by...
Monitor receiver (CIR21944E)
This receiver was found in a documentation by Gernsback from 1960. The circuit uses high impedance...