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Wake Up to Dawn Light in Your Window All Year LongView Instructable »
Hmm. I'm not sure how you got here. I just Googled my title and found the whole thing, without any payment upfront. If you click on the little "download" icon the figures should be intact.Unfortunately, Apple and others are moving away from physical audio connections entirely, so in the future Bluetooth may be the only way to go.
Nice idea that would not quite work out of the box. The op amp would probably be OK with 5V from the USB port, but not directly on a single supply. Either that 5V still needs to be split by the voltage divider, or you need to make some other provision for the fact that the input voltage is going to swing both positive and negative relative to the common connection. The circuit could be redesigned for single supply operation. Have a look at https://www.ti.com/lit/an/sloa030a/sloa030a.pdf
Flowering Plants Under LightsView Instructable »
The chip should not get hot. Something is very wrong with your circuit.
The 4558d is a very old chip that is listed to to need a minimum ±5 V power, so it might be marginal here. But my guess is it will be OK. The 500K pot by itself should be OK too. Good luck.