Latest threads in Hobby Electronics Basicsshow only best voted threads

Subject Author Posted Replies
 
Battery discharger - will this work?
The circut is here: The idea is to discharge a NiMH AA cell at 500ma down to the point where the cell voltage is 1V. I picked the specific parts because I already have them in my junque bin. The idea...
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19
 
Computer Case fans
So I bought a case from someone off of craigslist but it didnt come with rear fans. How can I tell which size i need
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4
 
opening and closing doors
I'm fairly new to the internet and recently, I;ve been hearing sounds of doors opening and several minutes later, closing. Someone told me this is new mail in my inbox, but when I check, I find this...
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7
 
Audio-grade low-voltage op-amp
I'm looking for a low-voltage op-amp to be used as a difference amp to provide DC coupling to a USB sound card. So far, my quest has only turned up rather s-l-o-o-w-w parts like the LT1013, LMV358,...
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5
 
Measuring science fair motor current ?
I helped a friend's 10 year old son build a science fair motor: a coil of wire (20t around a pill bottle former) supported above a magnet by paper clips with the tops bent into a U. The coil has #14...
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Recommendations for prototypes
--Have a circuit board all drawn up; now looking for a shop to make the prototype. Recommendations appreciated. Board is small, maybe 3" x 4" and eventual production quantities will be low; maybe 2...
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4
 
design help
I'm ok with fixing and adapting circuits but not so good with design. I've come up with an electronic switch circuit but I think it could use improvement. The goal is to turn on a 12v relay with a...
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356
 
hey i thought you might want to see this
while surfing the net last night, i found a website with some pretty good information on it. heres the link think you all should go and check it out, it helped me out a bunch. Anyway thank you all for...
 
Basic Electrical Safety Question
Hi, I am hoping any of you guys can solve my puzzle. If a person is touching the neutral line, the potential is already zero How come he still gets shocked? If there is a ground connection on the...
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push button LED light with modes
Hi, I'd like to build a LED circuit. I have a very basic knowledge of electronics, components, etc. I'd like to use a momentary push button, perhaps a small tactile switch. The circuit would light the...
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17
 
D flip-flop
why we use a D flip-flop,when we are getting the same output as the input?
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5
 
Where to look for datasheets?
I was looking at a pcb I removed from a dead microwave. I noticed a TI chip SN102977AN. I wondered what it is. Googling gets lots of hits that are useless. Generally sites showing someone else googled...
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7
 
? on small battery operated fluorescents
Once purchased a small flashlight with a fluorescent (6") built into the side, and a switch that let you decide which one to turn on. Ran on 4 AA batteries, for several hours. Wife fell in love with...
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47
 
another output Z question
Hey all I'm still trying to find the output Z of a low gain JFET preamp I'm working with. I'm using an MPF102, in common source configuration. I have a 1K resistor going from the 9v supply to the...
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3
 
Grounding between function generator and ADC
Hi all, I'm having some issues with a generated signal from an HP function generator, and I believe the problem may be a grounding problem. Basically, I'm emitting a signal with an HP function...
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