Amplifier stage with the T411E (T411E)

The pentode tube used in this circuit has 1.5 V filament. The circuit is a voltage amplifier with the 1U5 tube.

Timer 4049 (CB15094E)
This simple timer uses one of the six inverter ports on a CMOS integrated circuit. Rx and Cx...
Doorbell Tone Generator (CB18473E)
This circuit can be used as a residential doorbell. We found it in an English publication from...
Strobe 7400 (CB22418E)
In the old original version of this circuit from 1989, the LED is common (we recommend 330-ohm...