How can I make my own printed circuit boards?
Hi, I want to start making my own printed circuit boards to build some of the great projects I want from a popular tech magazine. I know it involves photo resist, a scanner, and some kind of transfer...
View ArticleHow to use a voltage regulator with a 12v solar panel
I have a smaller solar panel used to "trickle charge" 12v auto batteries that I want to use to power car cell phone and gps chargers. I simply added a female cigarette lighet recepticle on the end of...
View ArticleWhen / where should I use capacitors?
I appologize if this is a pretty basic question, I'm a software engineer by trade and do electronics stuff for fun. I'm trying to figure out when, where, and more importantly why you would use caps a...
View ArticlePowering a standard LED with 120 VAC
I want to power a LED with 120 VAC. I set up a circuit like the one in the attached file. I sized the resistor with ohm's law. I wanted 20 ma so that means a 6.8 K resistor with a minimum of 2.4...
View ArticleWhat parts are most worth salvaging from old tech?
Do you guys ever both salvaging your old tech? What's the oldest equipment worth bothering with before Moore's law renders it completely useless?
View Articleoptical sensor switch (photoelectric?)
I am trying to build an optical sensor switch for a small toy motor, but I am not sure where or how to start. I would like to make a photoelectric switch, or some type of optical switch that will...
View Articleoperational amplifier and comparator
Hello, I've learnt that op-amp can be used as a comparator ,so why there are components that they are reffered to as only comparators not an op-amp ,for example in isis proteus simulation program there...
View ArticleController for reservoir sluice gate
I am the engineer for a small HOA that owns/manages a 40 acre lake with 6 sluice gates. The sluice gates were installed to prevent the operation/destruction of the flashboard system originally...
View ArticleHow to balance parallel MOSFET's
I want to place several mosfets in parallel to handle more current, but am confused about the Gate resistors and something refered to as a "balance" resistor. From what I've read, this balance...
View ArticleReservoir sluice gate controller
I am the engineer for a small HOA that owns/manages a 40 acre lake with 6 sluice gates. The sluice gates were installed to prevent the operation/destruction of the flashboard system originally...
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