# Tag Info

1 vote

### Capacitor in AC

The 4 diode switches or a diode full-bridge rectify the positive current with twice the input frequency and almost the same voltage minus the 2 alternating diode pair forward voltage of 0.7V x2 ...

### Old sewing machine motor filter/capacitor schematic/wiring

About: Can anyone help me decipher the schematic so I can replace it using individual capacitors? I found here this quad-capacitor showing the diagram more clearly - just in case, I marked the ...
• 563

### Capacitor in AC

I don't understand what is the reason that the value of the capacitor amperage decreases after every phase? I was supposed that the amplitude would be the same in each phase, but it decreases. After ...
• 379k
1 vote

### Replacing blown out capacitor in old projector

About the capacitor and pictures in the link, I did this collage, highlighting the C1 you mentioned in the lower right side. I also saw another Capacitor - an Electrolytic one, inserting a zoomed view ...
• 563
1 vote
Accepted

### Why do audio amplifiers have many capacitors in rows?

Polar e-caps tend to be selected for ultralow resistance, ESR to improve the attenuation of RF from the series L and DCR resistance. The actual equivalent circuit of most caps looks like this. Keep ...

### Why do audio amplifiers have many capacitors in rows?

One reason is that large value capacitors tend to be taller, using multiple shorter ones allow them to fit into the same height as the rest of the circuitry. Another reason is that capacitors have ...
• 3,556
Accepted

• 16.5k

### Why is a capacitor considered a short circuit at start up?

When the circuit is powered off, the capacitor sees a 0 Hz (zero hertz) signal which, by chance, is at level 0 V (zero volt). When you power on, there is a transient: 0 volts change to X volts. That ...

### Why is a capacitor considered a short circuit at start up?

You are mixing up two very different concepts. When you talk about impedance you are implicitly examining the behavior of the system in an AC steady state condition, i.e. when excited by a sinusoidal ...

### Why is a capacitor considered a short circuit at start up?

Because you do not have infinite energy. The voltage across a capacitor is proportional to the charge on its plates. This means that during a transient, such as the charging at start up, the voltage ...
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### Why is a capacitor considered a short circuit at start up?

This phenomenon can be better explained in time domain than in frequency domain. Strictly speaking, a capacitor is not a short connection since its terminals are separated by an insulator. It rather ...
• 9,161

### Why is a capacitor considered a short circuit at start up?

You are mixing up two different operating regimes for the capacitor. In the case where a constant AC sinusoidal waveform is put across a capacitor the impedance = 1/2.pi.f.C. In the case where a DC ...
• 7,763
1 vote

### Measuring capacitance with STM32

In order to use measure capacitance and inductance we use AC sources. Emulate a AC sine source using the microcontroller , make a Sauty bridge then feed the differential input of the Sauty bridge to ...
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1 vote

### Measuring capacitance with STM32

The proper way to measure capacitance is with a constant current or by impedance ratios at some frequency. Consider the timer method. Use two threshold voltages, (one could be 0V) with a difference ...

### Will this charge a capacitor?

A nail in the dirt is not a ground. In any case, no grounding is required. Here are three ways for you to charge the capacitor. Using a single diode. Using two diodes. Using four diodes. It should ...
• 9,737

### Measuring capacitance with STM32

You have the GPIO going to the capacitor through a 1 Meg resistor, and then you've connected the ADC input to it. What is the impedance of the ADC input? If I read the datasheet correctly it is 50 k. ...
• 3,556

### Will this charge a capacitor?

Sure the C T is the accepted way to go .Sure the 4 diode fullwave bridge will do this when a CT is not present .If you want to use just 2 diodes with no CT you could place 2 resistors to ground one on ...
• 12.4k