3-tubee reflex receiver (T1658E)

Found in a 1924 documentation, this circuit is powered by 3 batteries, two of which are high voltage. The output is a high impedance headphone jack.

| Clique na imagem para ampliar |

RIAA Transistor Amplifier (CB19171E)
This circuit, from the 90's, is intended for operation with vinyl record players of the time, as...
Instrument Scale Modifier (CB4159E)
Using a zener diode it is possible to change the linearity of the scale of an analog instrument by...
Chime delay (CB9679E)
Found in American documentation from the 1980s, this circuit prolongs the ringing of a doorbell or chime...