Pulse generator with delay 555 (CB8922E)

We found this circuit in a Hands On Electronics from the 90s. The delay is given by the formulas next to the diagram.

Power Supply 15 V x 300 mA (CB17356E)
This simple, unregulated power supply is indicated for non-critical projects that require currents up...
Residential Alarm (CB16553E)
This alarm uses several sensors that directly trigger a sensitive relay. A larger relay can be...
Simple Metronome (CB11824E)
This is a well-known oscillator configuration with complementary transistors. In this case, the...