Latest threads in Hobby Electronics Basicsshow only best voted threads

Subject Author Posted Replies
 
Why ic pins ( on hdd / mboard ) are not covered by lacquer to avoid short circuit ?
I think hdd & mboard makers don't want their products to last longer than their warranty periods, so users must buy new models. My mboards / dimms / hdd all have short circuits caused by carbon in...
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Multiple Sensor Array
Hi guys, I'm building a temperature monitoring system. I've got about 8 Thermistors reading into a networked IO device. I'm feeding the Thermistors from a 5V supply (LM317) through a potential divider...
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Line conditioner protects against momentary brownouts?
A line conditioner that includes a voltage regulator seems to have done wonders for my computer system (recently replaced my old model with a better model), especially when my house power was not very...
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building a small amplifier for the first time
I finally settled on this one: Questions: 1. Would a 2N2222 work instead of the 2N4401? I've got a bunch of quad-2s in my bin. 2. Would it be ok to substitute 1-ohm resistors for the 2.2 ohm resistors...
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How to power a single LED from a 12v supply?
Over this coming winter, I'm planning a complete refit of my small boat's electrical system. One of the things I would like to add is a tiny light at the masthead, to illuminate at night the flag I...
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Autotransformers
I understand the basic idea of an autotransformer, using a tapped winding to raise or lower a voltage and no isolation (which isn't necessary for my application anyway). If I have a 60VA 240V primary...
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Harm in leaving a cell phone plugged into the wall all the time?
Will it be harmful to the cellphone battery if i Leave it plugged in all the time? I'm trying to use it more, by thinking of it as just another land line phone.
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run 6V DC motor @ 12V w/ PWM ?
If I run a 6 volt dc motor at 12 volts, using less than 100% PWM, will it be ok? or will it still burn out. thanks
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questions about quasi complementary audio output stages
What are the drawbacks with quasi complementary audio output stages, like, say, this one: Do they give more distortion than the usual Sziklai output stages? I understand that 40 years ago good PNP...
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Simple DC voltage modifier
Hi, It's been years since I've done any basic circuit design, so I'm looking for a couple of pointers in the right direction to get me started. I've got a heating system control and a hot water boiler...
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HDS-200 / Motorola 6800 Development tool
Is there any interest out there in this (antique) development tool? I've got one (it takes up a lot of space!) that I would like to part with. Thanks, TomC
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Need help hooking up illuminated pushbutton switch
Can somebody please help me figure out how to hook up an illuminated pushbutton switch that I bought to my range hood? The switch is Radio Shack part # 275-671: Here's a link to the schematic which...
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Brooks 1931 paper on inductance design
In case anyone wants it, google books has H. B. Brook's 1931 paper called "Design of Standards of Inductance, and the Proposed Use of Model Reactors in the Design of Air-Core and Iron-Core Reactors."...
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Inductor calculation?
I am trying to calculate the inductance of a multi-row, multi-layer air-core coil that has a square winding cross section, zero magnetic coupling to any other object. Conceptually, it's a Brooks Coil,...
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inductor current question
Hello, ok, say you've got a DC voltage supply in series with a switch and an inductor, the inductor ties back into the power supply completing a circuit. ok, the switch is closed for a little bit then...
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