macusking

joined 1 year ago
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13
How could a DC oscillator produce AC after a capacitor? (discuss.tchncs.de)
 

Hello there, This oscillator is a 0V +10v DC oscillator, which after current passes through the capacitor, it produces a -5v +5v AC on the resistor.

We've all heard that AC removes DC component and let's AC pass by. I understand the dynamics of this circuit in case the oscillator were operating with AC (capacitive reactance), however this oscillator is DC, the voltage across the capacitor never changes polarity (since the other side of circuit is ground), so what gives? And why the 10V DC is split on half +5 -5 volts after the capacitor? Thank you!

Would this circuit to use an HR202 humidity sensor actually work? in c/[email protected]
[โ€“] [email protected] 1 points 1 year ago

Thank you. I'll try this approach!

Would this circuit to use an HR202 humidity sensor actually work? in c/[email protected]
[โ€“] [email protected] 1 points 1 year ago* (last edited 1 year ago) (2 children)

Thank you. Do you recommend me something (circuit) else? The 2.4v zener would provide about 2.4v. To keep 1.2V exactly half of the zener produced by the zener, I was considering split its voltage with 2 x 10k resistor in series and feed into an opamp in buffer configuration, so even it the 2.4 reference changes a little bit, the other side of circuit would be always zener / 2.

4
Would this circuit to use an HR202 humidity sensor actually work? (discuss.tchncs.de)
 

I wanna run a HR202 moisture sensor and an Arduino. Yes, I picked a HR202 to challenge myself to make it work. I already have some easier-to-use SHT40 in stock.

This sensor can only run with AC 1.5Vpeak max. So, I've created this little circuit to provide AC, and I'll only read it when the oscillator output is HIGH, so I can read it briefly at the same time with the help of Arduino's ADC. Could this circuit work? Thank you.