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  1. hello, I am stuck with a dilemma which might or might not have a simple solution. more: giá chung cư 17 phạm hùng I have a psu supplying 46Vdc unofrtunately i need to step this down to several different voltages. 1) 14 to 20Vdc (best would be 16Vdc) to power a micro mainboard power supply thingy, using approx 100W 2) 12Vdc form as well a led strip, a fan, temperature sensors (LM35 i believe) and arduino atmega 2560 board 3) 5Vdc so i was thinking (maybe wrongly) to use a couple of 100W resistors in series (5KΩ - 5KΩ - 5KΩ&2KΩ - 2KΩ) and use it as voltage divi
  2. Hi! I'm new here so if this topic has already been covered or if it's in the wrong category, be gentle. more: can ho 17 pham hung I know enough about electronics to make me dangerous. I have a wood lathe and want to power it with a DC motor to be able to get better speed control. I have seen people use treadmill motors. I happen to have a few old 24 volt electric scooters (the larger kind with seat not the smaller stand-up only kind). I'd like to use that motor. I want to use AC to supply power to it. I'd like a speed control that goes from 0% to 100% and be able to reverse rotation. Wh
  3. Hello all, I've arrived here after what feels like hours of scouring the web for the info I'm after but I feel like I'm just not getting the search terms right or something. So here I am, first time poster hoping for some guidance to what I think should be a simple question? more: dự án iris garden mỹ đình I'm actually a chainsaw carver but have been known to solder a circuit board to some stepper motors and wire up cars and boats and bikes so I'm not afraid of electrical stuff and know my way around heat shrink, heat sinks and connectors. I'm currently working on a carving with some
  4. Hello! This is my first electronic question. The image I have attached should be self-explanatory for a better understanding of my project. However, I need to know do I have to add any additional cable? more: iris garden trần hữu dực I am going to utilize 3 lap top computers (A, B, & C) and connected computer A to B with a USB 3.0 cable. Then I will also connect computer B to C with a USB 3.0 cable. I am going to access data from computer A with computer B. Then I will access data from computer B with computer C. I am utilizing MS Excel on all lab top computers. I will hav
  5. Hello, The following below document (RDR-32) is for a 150W PFC’d LED streetlight. Its noticeable that the schematic on page 8 simply shows the earth connection being simply connected directly to the neutral. Surely this is not wise as RCD’s could be tripped? more: mỹ đình plaza 2 Surely for the sake of common mode noise mitigation, it would be best to have Y capacitors from live and neutral being connected to the earth connection? The schematic on page 8 shows no Y capacitors in the mains input section. Isn’t this a missed trick? Another point is that in a streetlight, the
  6. After recently becoming somewhat broke, my wife and I were forced to settle in a small town in a very Wild-Westy part of New Zealand: Deepest darkest Southland. Like many of the inhabitants of this hillbilliyish community, our hard-smoking, hard-drinking, benefit-frauding 'neighbours' on the north side, are unable to function without a constant diet of loud 'music'. more: dự án eco dream (I use the term 'music' in the loosest possible way. It's just repetitive, thumping noise) I won't detail all of the hoops we've jumped through to try and get this racket to cease. Suffice to sa
  7. hi would anyone know the answer to this . During a thunderstorm my girlfriend had breaker for the outlet for use near the sink OK the power surge tripped the breaker in the bathroom . She has a leaded glass night light that she puts there if nothing else is being used it has a switch on it . Well she told me in the morning that it was not working so i reset it Went to check to see if outlet was hot by plugging in the hair dryer IT WORKED THE Light STILL DID NOT . So i went to the kitchen with the bathroom stain glass light with the switch plugged it in it to my surprise it worked. WHEN i tried
  8. Ill limit you with the boring details, but I have an electronic device that I can attach to my bike tire and it produces power and in return it can apply resistance to my wheel to simulate a steep hill or I must produce a certain number of watts. Its a great tool for training.... mehr: chung cư sun láng hạ I heard a pop and then took apart the unit to find a burned spot on the PCB. I later found the fried SMD melted to the inside of the plastic housing. Looking at everything, I found a part number for the replacement resistor and I plan on ordering that first. Ive never had to solder or
  9. Hi, I need to measure the strain in concrete beams. For this purpose I have purchased data acquisition system with a complementary 1/4 whetstone bridge circuit. The complementary circuit consists of 3 resistors of 120 ohm each. My strain gauge is 120 ohm and the gauge factor (k) is 2.11. The data acquisition system is modern and digital. Now, after connecting the strain gauge to the complementary circuit and exerts excitation (Ue) of 2.0 V (output) to the whetstone circuit and then loading the beam so that strain happens and the data acquisition system reads the voltage from the whetstone
  10. Hello all, I am sure many have seen the debates on the internet by the car audio guys of the cheaper CCA wires vs pure copper wires when used to deliver high amp DC current. I am here to ask your opinion based on my situation. I have a 300w solar array, 400ah of 12v batteries, and a 50ft round trip circuit to my 2000w AC inverter using 1/0 AWG copper clad aluminum wires which I put together 2 years ago and is functioning off-grid correctly. I went with cheaper CCA vs welding wire or marine wire at the time because of the cost. After reading and watching many CCA (coppe
  11. Hello! I recently got an Off-brand arduino kit as my first taste of electronics. It came with the board, components like LEDs resisters, breadboard, jumper wires etc... the problem is that when I try to plug some things into the breadboard, it rarely works. I struggle to plug anything in and when I do, I pretty much have to hope that I plugged it in right, have to check all the connections constantly and plug some of them half way to get it to work. the most I've been able to do is three flashing LEDs. It is so scetchy that if I bump the table a tiny bit, it stops working and I have to red
  12. Hi All My ViewSonic monitor quit working and I know it is many times a capacitor issue and in the ViewSonic case, in the power supply unit. I pulled the power supply and I can see various locations where capacitors/other components leaked. I posted a picture of what I found and have a few questions about the components. The arrow labeled "A" points to three components that appear to have leaked. What type of a component are they? The arrow labeled "B" (middle bottom up arrow) points to another light blue component. This is a capacitor, yes? The last arrow "C" points to th
  13. Hello everyone, It's been years since I've posted here, and I remember there was a "chit chat" forum, but couldn't find it; please move my post to an adequate forum if it doesn't really belong here. I am working on the translation—from English to Spanish—of the essay "Demystifying Single-Supply OpAmp design" for a course in my Alma Mater, and I would like to know if it would be okay to post it, after it's finished, in a freelancer website as a sample of my work. The essay is found free at the EDN Network website, but since I probably have to post somehow the original for reference an
  14. I just bought a new house. On one wall in the kitchen is panel with 3 switches. I have know what 2 of the switches do (both are ceiling lights), but the third one does not seem to do anything at all. My first thought was that it controlled one of the outlets in the kitchen or family room right next to the kitchen, but after taking a small lamp around to every outlet that I could find I could not identify what the switch was for. During my testing, every outlet tested had power and lit up the lamp ( I did not test the voltage at the outlets, though). So the next thing I did was take t
  15. Hello, Yesterday I was watching a movie, and my HK AVR 147 just stopped working, and I could heard the relay switching off. I turn off the amplifier, and turn it on after 2 minutes, and it started to work for about a couple of seconds, and stopped again (again with a relay noise). Now, it doesn't work at all. I power the amplifier, it stays on standby (amber color). When I hit the button to start the amplifier, it turns blue, but with no relay switching noise. After 10 seconds, it returns automaticaly to Standby mode, with the amber color. Could anyone help me on this matter?
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