# help

1. ### Basic electronics, configuration of OPAMP circuit on breadboard

Hello everyone, I am an optical Engineer, with a little electrical experience, but it has been a long long time ago since i have made any kind of circuits my self, however that is the "case"here, so i am hoping some one would be willing to assist me. Normally i would just purchase the component...
2. ### Problem integrating a TL072 audio mixer circuit on stripboard

Hey! So I've been trying to build a modular synth on/off for the last year or so, and one of the most simple projects I thought I should start with is a mixer circuit. I found a really simple circuit schematic and shortly after got it working on breadboard, with absolutely no problem at all...
3. ### I need some help putting together a wideband, radio frequency amplifier and a UWB antenna.

Hello, I would really appreciate it if there was somebody who could just help me by telling me how to make this. It needs to be only the very bare bone components without any filters. I just need to be told what I need to buy and how to put it together. Ultra wideband, frequency range...
4. ### I bought an HP 54110D Oscilloscope and I need help before I smoke it.

Hello, everyone I am new to this field, and I am trying to learn the ropes. I recently bought an O'scope an HP 54110D 2 channel, and I need to buy probes for it and I am trying to figure out how I should go about it: Questions: 1. The input Pods have specs that are confusing to me. One of...
5. ### USB Hub Splitter Problems

There is a cable in my workstation that leads from the keyboard/mouse to the WS itself. For some reason, it goes KB/M -> USB cable -> Female to female USB adapter -> 2 port USB splitter -> USB cable -> workstation. The part in question is the USB splitter (specifically a "Cute USB Mini 2-Port...
6. ### wellhise wh-890d multimeter problem

Hello i have a wellhise wh-890d multimeter. Yesterday i was trying to charge a motorbike 12v battery i unplugged the charger to check voltage then i checked the amp it is taking then i forgot the probe was in the amp hole (left 20A hole on the photo) then i put the meter on voltage mode and i...
7. ### AC DC conversion and power drill diy bicycle motor

I have a few questions based on some little projects have been working towards finishing. The first one has to do with me trying to use my 120 AC powered corded drill as a simple converted bicycle motor. Show theme simple enough but my issue is how do I convert it to run on a battery? I would...
8. ### Nand circuit, placement of resistor.

Hey everyone, I'm new here and also a newbie who is teaching himself. I have one question: How come if i put resistor R1 before the output, the output is always 1? Even if A and B have an input signal.
9. ### PCB help for a LG tv

Hey there , my 1 year old tv recently stopped working , I’m not familiar with these stuff but I’m trying to figure out which is defective in order to replace it. The tv has no standby light showing and does not turn on, the power supply board keeps making a ticking sound, I have checked the...
10. ### Circuit Analysis

For Question 2.1, is the power 500W or 100W ? Do we need to apply the passive sign convention rule for power in whatever cases? Also, i’ve Learnt that we can check answers by balancing power in a circuit. But the power in this kind of circuits don’t balance out, but it is still valid. So when...
11. ### Assembly Language Program

So we've been instructed to write an assembly language program to display numbers 0-9 on a common anode 7 Segment Display and simulate it using the Proteus Software. (8051 microcontroller) (And 0-F as well) I'm a complete beginner in this field and was hoping that I'd get some help here from...

Hi guys I am on a little project (ecg with an arduino) I followed all the topics , the diagrams to wiring , electrodes placement.... But never I can get an classic ECG GRAPHIC Please help Best regards AD8232 Gnd-gnd 3,3v -3,3 v Output -a0 Lo- dig 11 Lo+- dig 10 Sdn- none Code: Void setup() {...
13. ### How do you identify ICs and other components on a circuits board

So i'm currently trying to take parts out of a Bluetooth speaker's circuit-board and find the Bluetooth module for a DIY project. I looked at the board and some ICs and tried looking them up to no avail. So How Do you read an IC or any other components on the board Or even find a schismatic...
14. ### Help: Redirect New User to Appropriate Sub-Forum for Product Design

Hi, Being a new user I would appreciate it if someone can redirect me to the appropriate sub-forums for my technical question. Context: Well, I'm looking to build an open-source Automated Optical Inspection device(non-profit). I would like to ask technicians, EEs, CEs, and even hobbyists who...
15. ### Pressure sensor

Hi guys I need your help to making work the pressure sensor MPS20N0040D (module with hx7110) , I uploaded the sketch , but I can't get a right graphic , it's seems to be not fonctional !!! It's the same graphe with & without the module connected To the arduino !!! Please help Best regards
16. ### I need a weird heater for reptile tank

I have a 3 tier reptile tank, but apparently there are not other things to heat them other than lamps an mats. Needless to say I need to know if there is a way to build a circuit (or buy) one that can also regulate the temperature output with an accuracy of 1+/- degree. I basically am going to...
Need some insight about a plot found in the Fundamentals of power electronics second edition book. I don't really understand why it is written like this. Left side $$\frac{I}{V_{g}/R}$$ can be rewritten to $$\frac{1}{D'^{2}}$$ so it is basically "just" duty cycle. The book states that the...