# voltage

1. ### Minimum resistance of NTC thermistor when connected series with bulb

Hi, just curious, A bulb (30 Ohms , 100W) is connected in series with NTC Thermistor (200 Ohm at room temperature). Since the ohmic resistance of NTC Thermistor will decrease over time, how long does it take normally for a thermistor from 200Ohm to reach close to 0 Ohm) which means all power is...
2. ### AC-AC step down voltage + frequency converter simulation (LT Spice), file provided

Hi, below is a AC-AC frequency converter with a step down voltage from 200 to 20 Volts Question: As you can see that the efficiency is 1.55/2.251 which is about 66%. May i know how to improve the efficiency of this circuit. I have tried to change the capacitance of capacitor since it...
3. ### How to lower watt output

Hi, I am kinda new to this stuff but I have 16mA 3.3V AC output wich is 0.0528 watts but I need to get it to 50nW (0.05 microwatts) I tried finding something butndont really know so how do I do it?
4. ### How can i make a power supply with arduino due?

hello everyone, i got a question: I need to make a power supply to heat a heater, for that I need to use an arduino due, and use one of the analog pins (it´s like a built-in DAC) of this microcontroller, and draw voltage from that pin, with an external current source or something similar, I...
5. ### Peavey Centurion Mark III head with high DC voltage output

Hello, I have a 1980 Peavey Centurion Mark III head that was buried in my garage unused for 15 years. I knew it had problems (it's not mine, i got it from a friend who was throwing it) so before doing something i checked all the components and everything looked great. Once done I plugged it to...
6. ### Measuring cell voltage, which oscilloscope is good with wave generator combined

Good day everyone, New to the field. I was wondering if you I could get an expert opinion and advice on my future experiment . First phase of my experiment is to measure the voltage of set cells from different tissues. 1) Which Oscilloscope should I use to read voltage as slow as 0.07volts...
7. ### The relation between Vin and Vout (diodes circuit)

Hi, can anyone here tell me if the function I found that relates the Vin to Vout is right? So I made a mesh analysis to find the current in the first mesh (left to right) and in the second and finally got that the Vout = (2/11)*Vi +6.328 (is it right?) threshold voltage = 0.7V
8. ### Problem with Electrical Circuit Question

Hi! I have a question related to electronics: Someone told you that there might be a problem with the electrical circuit: In addition to the standard 50Hz alternative voltage, it mights exist another disruptive frequency at 50.5Hz. For how long, at least, should you measure the voltage in the...
9. ### Need your advices on how can I estimate the voltage at the terminals the thyristor switch

I am working on a static transfer switch which aim is to allow supplying a load with 2 different sources in order to have a redundancy when feeding the load. The head to tail assembly allow the current to flow in 2 directions (for each alternative of the input current) The working condition is...
10. ### AC voltage rating of capacitor?

I have a doubt regrading the Ac voltage rating of the capacitor. I am using a capacitor which is rated for 630V DC. I want to know the Ac voltage rating for this capacitor. If anyone have come across this please add some suggestions...
11. ### voltage subtractor

i'm working on a arduino based BMS which have to measure voltage from a multicell battery which is connected in series. i can measure the voltage of the cells by individually grounding them. But what i want to achieve is to measure single cell battery voltage when they are connected in series. I...
12. ### I want to learn thermocouple type k,j etc,

Hello evryone, I start studying Eletrical and computer engineering and I want to learn thermocouple type k,j etc, however I've been searching and I can find to measure temperatures is using water bath 0° in cold junction so voltage will be the same as thermocouple tables on google, however...
13. ### Need your advices on how can I estimate the voltage at the terminals the thyristor switch

I am working on a static transfer switch which aim is to allow supplying a load with 2 different sources in order to have a redundancy when feeding the load. The head to tail assembly allow the current to flow in 2 directions (for each alternative of the input current) The working condition is...
14. ### Inductor current

An inductor of 10H has 1omh internal resistance. What is the current through the inductor after 10V is applied for 1 second?
15. ### Using a HVGEN10AC v3.1 to drive my Voltage Multiplier

Hello, I recently bought myself a HVGEN10AC v3.1 to drive my Cockroft-Walton Voltage Multiplier. At 24V input it can produce 10kVpp. I want to connect it to my multiplier but the transformer only has 1 HV-Output and the Voltage Multiplier needs 2. As you've probably already noticed I'm very new...
16. ### How to select appropriate components?

I've just started tinkering and I'm having trouble with a pretty basic concept: reading and selecting components. I have some push buttons that say ACDC 24V — does this mean in need 24V of AC -> DC power for the component? I have another push button that says: UI: 440V AC15 Ith: 10A DC13 —...
17. ### wiring an arducam with the power line on a transistor

I've set up an arducam mini 2MP plus with a nrf52DK (similar to an arduino for this set up) to take pictures. Ive got the board and camera working when the camera is wired with the VCC line and GND wired directly into the boards 3.3v line and ground pins. The arducam uses about 100 mAmps when...
18. ### Li-ion cell charging module resistor selection?

Greetings. A vendor selling TP4056-based 5 V charging modules for Li-ion cells specified the following resistance values and resulting current for selecting the current-programming resistor: R (kΩ) I (mA) 30 50 20 70 10 130 5 250 4...
19. ### Help me understanding the delta and star in 3 phase voltage !

To solve this question all I know is I had to change the delta source to star shape (wye), then to find the current is using ohm law's with the voltage divided by the impedance which in the same line I'm confused with this question, does the position of the source in delta and impedance matter...
20. ### Adapting an old CRT Viewfinder ( 9.3 V DC / 2.7W )

Quarantine project: Adapting a Sony BFV-20W viewfinder Scroll down to skip the background info As a cinematographer, I've always really felt most comfortable shooting with a viewfinder. However modern electronic viewfinders all exist in the "prohibitively expensive" class of filmmaking...