Latest threads in Hobby Electronics Basicsshow only best voted threads

Subject Author Posted Replies
 
self-energized synchronous rectifer circuit?
Hi all - I've been reading a little about synchronous rectifiers as used in a switching power supply. I've also seen some references to a "self-energized" version of the synchronous rectifier which...
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Help with RC fourier series
I am looking for a fourier series to approximate the following wave form: A constant DC voltage source charging a capacitor wired in series with a resistor for a time t=2L and then the capacitor is...
 
differnce between theatre and tv
i have doubt to watch the movie in theatre and tv In theatre's why all the lights r putoff, may be it will effect the eye's or any any other reason and in home puton the lights and watch the tv what...
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Soldering Station
I need a new soldering station to replace one I lost during a move. This is for hobby use in microcontrollers and general analog/digital work. Is a Metcal MX-500 a reasonable choice for these...
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how to flip a relay by digital signal
Hi, What would be an easy way to turn on a relay by a digital signal. The relay would be hooked to a 220 V AC device.
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mosfet audio quality
How does this IRF530-based circuit compare with, say, an LM3886? I thought this would make a good first project, but if it doesn't sound so great, then why bother...? Anyone have experience with this...
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Add a two way switch to this circuit
Hi, Please have a look at the circuit at: is from the article at The circuit it to turn on or off a AC bulb by a microcontroller. My question is, can we somehow safely add a manual override switch...
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Calculating DC Output Current From Unregulated AC Transformer
I have an application in which I need to determine if a transformer is suitable. Transformer is rated for 12VAC, 1.67A but I need DC. I could put a bridge rectifier and capacitor after it easily...
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being shocked by Amp casing
hi all, perhaps slightly off-topic but you guys have been of great help to me in the past When I was installing a new hifi amplifier last night, I realised i was being lightly shocked each time i...
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Question: capacitors as special use batteries?
I recall from my hobbyist days that high-voltage capacitors can keep a charge for a significant amount of time, especially if they are cut- off from the circuit subsequent to charging. I'd like to...
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Help needed designing square wave osc (555)
Hi, I've been trying to calculate "standard" values that would make me a 555 R1/R2/C1 square wave oscillator with a 50% duty cycle operating at close to 30Hz. Can someone assist? My numbers come out...
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Help needed finding oscillator values
I would like to build 2 square wave oscillators from a 555 timer using the classic R1/R2/C1 configuration. I would like them to have a 50% duty cycle (or as close as can be) and operate at 30 and 60Hz...
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Transistor Current Question
Hello I was hoping someone could explain how to do this calculation for me. I've got 3 transistors and 5 RGB LEDs, and I need to use the transistor to drive them, as my microcontroller can't source...
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1N2071 diode speed
I found four 1N2071 diodes in my junk pile. Apparently the 1N2071 is an obsolete diode - Mouser doesn't carry it anymore. I looked up the datasheet for the 1N2071. It seems designed to operate at 60...
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Question about static electricity
I bought a USB drive, and it came in a small plastic shell package. Is it safe to assume that this plastic material is anti-static? I have not yet opened the package, and I left it sitting on the...
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