Calculating output voltage


Joined Aug 1, 2013
The output is a half-wave rectified sinewave. Beyond that, your question needs a lot more work.

If you are asking what the output voltage will be if measured with a digital voltmeter, it depends entirely on the load. It has a peak value, an average value, an RMS value, and an incorrect DC value on a meter - and all four of these are different numbers. If the load is a resistor, then the 1 M resistor in your drawing is one part of a voltage divider. If the load is a capacitor, then the size determines what will appear on a meter.



Joined Nov 23, 2015
The output voltage should activate the optocoupler
The measured voltage output was 0.5V but the optocoupler didn't activate, so I think it should be around 5V for it to work
Not enough current to turn on the optocoupler?
Self-assigned homework? If it is assigned homework you will get guidance, not answers.


Joined Nov 23, 2015
Can someone tell me what is output voltage for this scheme?
To get the 20 mA or so the optocoupler needs you need about 11,000 ohms, but that would mean you have to be a 10 Watt resistor. The voltage across the LED sets itself. (Maybe 1.2 V?) And yes, use a protection diode.