# Questions tagged [dc-transformer]

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26 questions
60 views

### What calculation can be used to predict the voltage across an air gap as a plasma spark discharges over 1ms?

I am trying to determine what voltage and instantaneous current is available if using a spark gap in air or other gas. Comparable to an auto ignition. This will be DC current. There will be a main ...
94 views

### Ideal DC Transformer in LTSpice

I am conducting some simulation work where I would like to incorporate the LTC3588-1 component model in LTSpice. I have an electrical model of a physical system that requires the use of an ideal DC ...
460 views

### Why is the transformer impedance given in percentage?

I have just talked to an Electrical Engineer and he referred to the impedance of a 3 phase transformer/rectifier with line reactors as 41% (8% transformer and 33% reactor). I asked him what these % ...
89 views

### Maximum voltage and current input of this circuit?

I am looking to assemble a power supply with an output of roughly 600 watts. One of the components required for such an apparatus is a 40 kVDC, 20 mA flyback transformer that I managed to find and ...
307 views

### 9V to 400V DC-DC Converter

I need to build a Geiger counter power supply circuit that will provide a 400V DC output out of one of those 6LR61 9V batteries. I thought about using a 555 timer to produce a square wave, feed it ...
64 views

### Flyback Converter with multiple DC outputs

I am trying to understand how (step up) Flyback Converters work, since I need to design one myself. I am not at all new to electronics and I understand the fundamentals behind them, but I am totally ...
67 views

### how to make an easy dc/dc transformer to run a lenovo laptop on 20 volt from a 12 volt battery [closed]

I was thinking of making my own dc/dc converter for my laptop. The original Lenovo charger can give 20 V at 4.5 A. I I have a few questions: right now I wanna build a 12 volt to 20 volt converter. I ...
420 views

### Will a 2000w Step Down Transformer be enough to safely power a Japanese Oven Toaster? [closed]

I recently acquired a Japanese oven toaster, with a maximum power consumption of 1000w at 100v, and I would like to use this appliance in USA. I was told that for safety reasons I should get a step-...
91 views

### Solar battery charger and powerplant [closed]

In this circuit what is that transformer's rating. I am making this circuit So I need help on this topic.
135 views

### NE555 Controlled Transformer Voltage Spikes

I am attempting to build a NE555 timer controlled step up transformer (3:250). R2 and R3 will be variable resistors when it is completed. Input is 12V and I'm stepping that up to about 1000V. The ...
138 views

### neon sign transformer test

I have purchased a neon sign transformer for some experiments. However I think it is faulty as when I short out the HV leads I am getting no spark. In fact nothing. This is the transformer: 12V nst I ...
67 views

### 240v Split Pase to power 12v Dc fans and lights

Im re-powering an model-81 powermatic bandsaw with a 3Hp Leeson DC Motor(14a max draw) and KBCC-255 motor drive(fused @15a). I want to put some fans to cool the DC drive heatsink and LED pucks in the ...
262 views

### My DC-UPS - done right ? Advice needed

I'm working from a while ago on a DC-UPS concept, after I've put all the things together and I'm requesting from you an advice, can I start to build it or I have serious flaws in it ? Current comes ...
73 views

### mechanical oscilator concept to drive electric motor [closed]

I have been thinking about a project for some time now and am wondering how well it may work. I would like to make a sleve which could be run by a small electric motor ie from an old cd player or rc ...
261 views

### Improve input audio signals to car audio system

I am helping a friend to solve a low and not so clear sound to his car's audiosystem, when using aux-input in particular. He is getting great signals from CD or Radio, but when he feeds the ...
686 views

### Simulate center-tap transformer using two transformers?

I have a PCB that takes 3 input terminals: V-, GND and V+. On the manual, it is stated that ...
367 views

### Output stability of step-down regulator connected to vehicle battery

I do not have access to an oscilloscope, so I ask here. Short version: I charged a phone from a motorcycle battery. Phone battery broke. Question: Can using a running vehicle's battery as a step-...
778 views

### Why does my new 220V AC to 12V DC transformer only allow one Halogen light to work? [closed]

I'm trying to revive an old Ikea "Trettio" lighting set. The set is made up of a 220V to 12V transformer and 5 Halogen lamps connected to it in parallel. Remembering that the original transformer was ...
543 views

### Stable 48VDC from 220VAC?

I'm trying to get a stable 48VDC power source with at least 500mA. I have a power transformer with two secondaries, each with 24V 0,73A. The transformer is rated at 35VA. What I've tried is connecting ...
422 views

### Can I connect the negative terminals together on two LED drivers?

I have a white, adjustable-color-temperature LED strip that I'm trying to power. The LED is basically composed of two separate LED circuits -- one at 6500K and another at 2700K. The strip has one ...
74 views

### psIsolation Transformer DC 12 volts

I want to use 12 volts DC and step it up to 400 volts AC or higher at 100khz. I am buiding a signal generator that outputs a sine wave or square wave with an adjustable frequency of up to 100 kHz. I ...
393 views

### Create a Time-Variable Dc Power Source

For some reason, I need a Time-Variable DC power source that changes it's value according to time. I need this changing of value to be controllable. I'll put it this way : Say I have a 12 volt DC ...
2k views

### Identifying power supplies / DC adapters

I have a box of miscellaneous power supplies / AC adapters / transformers / "bricks" which have no information on them about what they are for. I am trying to match them up to the devices they belong ...
3k views

### How to make a Taser? [closed]

I am new. I'm from grade 6,so I am pretty much a noob,but I want to make a taser with an output of 10 to 20 kv dc. The power supply is maybe 9 volt batteries or 6 volt batteries but not car battery ...