I am looking to trying to build a timer that will run in a loop constantly and every 30 seconds or so will switch on or off. I would like to have an LED to light up when its turned on. I basically could only come up with a simple 555 timer running with a variable pot. to ajust the time of pulses that I would like to set it on. I will have another resister and a capacitor. I also will have to add an LED to the circuit to let me know when its on. I am a beginner in all of this, so would really like some advice as to how I can make this work and maybe the measurements or other ideas for me to build this timer.