I'm having trouble with a simple astable 555 circuit. I've rewired it multiple times and get the same results each time so I'm confident it is not a wiring issue. I'm using a NE555P if that makes a difference. The measured values of the components are as follows: R1 is 8.15k, R2 is 9.97k & Cext is 0.0102uF. My calculated duty cycle is 64.5% but I'm only getting about 24% on time. The frequency should be about 5.13kHz and I'm getting 1.84kHz when I measure the output on pin 3. I've attached a picture of my breadboarded circuit as well as the diagram I wired it off of. I have tested the cap to ensure it is not shorted or open and it is not. I have also tried adding a cap from pin 5 to ground and that did not have any impact on the output. Any suggestions as to what the problem could be would be greatly appreciated.
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