Hey everyone I'm a total noob in need of some help here. I am just trying to make a very basic passive high pass filter, and a low pass as well (don't know how to set up a pass band filter but any tips would be helpful). I don't have a function generator, or oscilloscope, etc that I see in all the youtube videos for this. I have built a simple oscillation circuit (from Make: Electronics by Charles Platt which I am going through); I can change the resistors and capacitors to provide varying output frequencies. Now I want to feed that output through very simple high pass and low pass filters to an LED as a simple indicator. This has maddeningly frustrating, I must be overlooking something obvious. After several unsuccessful attempts I looked into the math for frequency cutoffs. I can use a 1 microF capacitor and a 47K ohm resistor for a cutoff frequency of 3.39 Hz (I have also tried a 1,000 microF and 47 ohm). I can configure my oscillator circuit to have an output of 4.83 Hz or 2.8 Hz. So when I set up my high pass filter I expect the 4.83 to pass but not the 2.8, and vice versa for the low pass. I have tried much slower or faster set ups too but still no luck. Attached is an image of my circuit on the breadboard. Can you tell me what I'm doing wrong, and in SIMPLE language (recall I am a total and utter NOOB). Thanks!
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