This tag is nearly useless. Consider using more specific tags to narrow your question down.

learn more… | top users | synonyms

0
votes
0answers
46 views

Circuit analysis

for 1 I got the answer as -R2/R1 for 2 Vout= -(R2/R1) * Vin which gave me -0.08 for 3 i think its infinifty but it says the answer is wrong. How do I go about 3 4 5 and 6? for 4 I tried Vout/RL ...
0
votes
1answer
18 views

Different Voltage Battery Backup Circuit

I saw a circuit on a website to make a backup battery circuit for a rechargeable 12v battery circuit. However, I don't anticipate regular power outages, so I believe that one non-rechargeable 9v ...
2
votes
3answers
129 views

“Hot-knife”/Thermal cutter power supply design

Im undertaking a DIY rope cutter project to avoid paying for the ~$150 storebought ones. Many resources online told me to use a light dimmer + transformer configuration and i had planned to go a step ...
0
votes
2answers
40 views

What type of switch am I looking for?

So I am making an audio switch, and I need a switch that takes 3 dual inputs and outputs one of them, or vice versa, taking one dual input and outputting it to one of three outputs. It needs to be an ...
0
votes
0answers
40 views

Adding a regulating circuit to supply 3.3v

Background I wish to power my circuit with a 18680 battery. My circuit actually has two parts: 1) a 18650 charger and power booster for USB at 5V, and 2) a Bluetooth LE module (running at 3.3v with ...
-1
votes
1answer
63 views

Portable 1A battery phone charger

I want to make a little battery-powered portable phone charger with 2x AAs that outputs 1A. I have seen similar USB powered battery chargers such as the Mintyboost but it only outputs 500mA. For 1A ...
3
votes
2answers
68 views

Does my device need reverse polarity protection?

I'm developing a device with changeable AAA batteries running at 3V. Since the end user can change the batteries there is a chance they may be put in the wrong way around. The circuit basically ...
3
votes
1answer
81 views

What do we need the op amp for in this current-to-voltage converter?

I'm still very new to electrical engineering and at the moment trying to get my head around the concept of the ideal op amp. In Fundamentals of Electric Circuits by Alexander and Sadiku the following ...
-3
votes
1answer
64 views

Is this diagram correct? [closed]

I have created the below mentioned circuit diagram: I just wanted to know that have I drawn a good/correct diagram or should I make any changes to this diagram? I have not added the resistors in ...
-3
votes
1answer
45 views

Circuit diagram of a household connection [on hold]

Often, multiple electrical outlets within a given room are all part of the same circuit. So how would you draw an "equivalent circuit" for a four-walled room which has a single electrical outlet per ...
1
vote
1answer
52 views

help related to frequency of schmitt oscillator

I have seen the CMOS Schmitt waveform generator circuit (i.e. figure 2nd) from the following link http://www.electronics-tutorials.ws/waveforms/generators.html I tried to simulate the circuit in ...
0
votes
2answers
55 views

TSOP382838 IR receiver keeps outputting signal even if no infrared light is present

This is a beginner question. This is my first time using an ir receiver. The one I have is a TSOP38238. I have setup a simple circuit that consists of a visible led and receiver. When I have no ...
-2
votes
0answers
47 views

Distortion in an amplifier

I need help with this exercise: "Given a common-source amplifier without any charge, it can be seen that there's cut-off distortion. How can you fix that, without changing the gain of the amplifier?" ...
0
votes
0answers
25 views

Simple Headphone & MIC Audio Mixer for PC Soundcard

This is a mixer On the left side we have headphones mono (Both left and right channels are common) and the other is microphone. So R2 (50K Ohm) adjust the volume for Microphone and R1 (50K Ohm) for ...
0
votes
3answers
95 views

Replacing wires with threads?

Is it a good idea to replace wires that get bent a lot (e.g., around a hinge) with conductive threads? It's a 5V device using up to 1A. Thanks
0
votes
0answers
34 views

Analyzing a circuit with given effective values, freshman EE

Here's the circuit: simulate this circuit – Schematic created using CircuitLab Values: Voltage shown at the volt-meter, 11V Current shown at the ammeter, 5A Current generated at the ...
-1
votes
2answers
51 views

Help fixing Honeywell doorbell broken circuit [closed]

My Honeywell RCWL330A1000/N P4-Premium Portable Wireless Door Chime dropped to the floor the other day and has not worked since then. I unscrewed the casing an found a crack in the circuit board which ...
0
votes
1answer
112 views

Circuit component

What is this circular component with two parallel lines in it? I've never seen this before
3
votes
3answers
183 views

Why is the impedance in the parallel resonant circuit maximum at resonance?

Why is the impedance in the parallel resonant circuit maximum at the resonant frequency? For example if we have two resistors in parallel the equivalent resistance is less than the values of the ...
1
vote
1answer
56 views

How can I power 7 IL151 5mm Clear White LED leds for a sculpture in a series circuit?

I am in the midst of planning a sculpture. The sculpture will require 7 IL151 5mm LEDs with a forward voltage of 3-3.5v . I have NO experience in electronics and I've been looking around and people ...
0
votes
1answer
40 views

Charging circuit for automatically 'switching' between 1A and 2.4A?

Does anyone know of a charging circuit that could automatically switch between 1A and 2.4A depending on what the device accepts? Suppose the power source is 3.6V which till be stepped up. For ...
0
votes
2answers
29 views

Drum trigger controller

I'm planning to make a drum controller (something like arduino) for pc using a piezo transducer as sensor, some electronic circuit, keyboard PCB connected to usb and sampler for drums in pc. I found ...
5
votes
1answer
290 views

What is this schematic symbol representing?

I found this symbol in some datasheet. But I have no idea what is it? Can anyone tell me?
0
votes
2answers
58 views

How To Build A POV Display Clock? [closed]

Hi I'm looking to make a pov display clock. The problem I am having is finding plans because I want it to rotate on a horizontal axis. I'm wanting to attach it to a magnetic rotor such as ...
-6
votes
1answer
60 views

What happens if an electric circuit has 99% resistance? [closed]

What happens if an electric circuit has 99% resistance? What if you let electricity come out of a the negative terminal, and only the tiniest bit of electricity comes back through the positive?
2
votes
1answer
66 views

Understanding a current sensor circuit

I'm struggling to see how the output of this circuit is $$V_{0} = {I_{s} R_{s} R_{L}/{5k}} $$ My work thus far: I understand the voltage into the base of the BJT is $$I_{s}R_{s}$$ I understand the ...
4
votes
6answers
2k views

How can voltage burn out an LED?

I understand how a current higher than what the LED is rated for can burn out an LED, but how does something equivalent happen with voltage? If the correct current is on an LED but the voltage is too ...
3
votes
2answers
62 views

Unusual Component Inside Photo Multiplier Tube Base

I am attempting to diagnose problems with a PMT (Photo Multiplier Tube) in our lab. I have taken apart the base, and begun drawing the underlying circuitry. I have come across a circuit component that ...
-1
votes
0answers
13 views

Adding another circuit to a full panel [migrated]

Is this the right forum for this question, as browsing all I see is regarding more "electronic" than AC electrical? Regardless... I'm looking to add a hot tub, and after my basement build out a few ...
0
votes
2answers
46 views

Solving RC filter by differential equation

I'm trying to solve the differential equation of a simple RC filter. What i got so far is: $$CRV'+V=V_0\sin(\omega t)$$ Solving i get: $$V == \frac{V_0 \sin(\omega t)}{1 + R^2C^2 \omega^2} - ...
0
votes
1answer
123 views

Can a circuit “just stop working” after not using it for a long time?

simulate this circuit – Schematic created using CircuitLab I had a very simple circuit that used a mosfet with an arduino to power a motor. The whole thing is run off of a 12v supply (5v ...
0
votes
0answers
57 views

circuit help voltage multiplier

Hello I am using a breadboard and I created the circuit below. I am using Two buttons to gain and fade a voltage output. I am using a voltage multiplier because my source is only 5 volts and I want ...
0
votes
2answers
40 views

Transfer function of a basic RC circuit

I'm having a hard time getting my head around finding the transfer function. I have a circuit that looks like this: ...
0
votes
0answers
41 views

Gain in common source amplifier

Let us consider the Common Source amplifier depicted below: We know that the gain \$A_v\$ of a such circuit is given by \$A_v=-g_mR_D\$, where \$g_m\$ is the transconductance of the MOSFET. We also ...
1
vote
1answer
68 views

RC-circuit - DE

Yesterday I was browsing through some questions in preparation for my exam and I found this one: Consider the circuit below consisting out of a capacitor C and two identical resistors R. For ...
0
votes
0answers
45 views

LM13700 based triangle wave LFO at low frequencies

I'm working on a LFO based around the LM13700 chip that will have its frequency controlled by a micro-controller. Ideally I would like to have the frequency range from around 1 Hz-1 kHz but am having ...
1
vote
2answers
78 views

Principle of Linear Superposition

I am having a problem applying the principle of linear superposition to the circuit below. My main problem arises in not know what to do with the capacitor and the inductor in parallel as well as ...
1
vote
2answers
81 views

Input range of operation amplifier

Lets have a look at the following circuit: (Input waveform is sinusoidal and Vpp would be ~32V) The input waveform should represent an AC Source from a ...
0
votes
2answers
31 views

Circuit with switch - express the current for different times

Consider the circuit below consisting out of a capacitor C and two identical resistors R. For \$t<0\$ the switch is open and the capacitor is uncharged. At \$t=0\$ switch is shut and the circuit ...
0
votes
1answer
50 views

LC circuit with AC-supply - current through the coil

A parallel LC-circuit is connected to an AC-supply as in the figure below. \$I_{tot}(t)=I_0sin(\omega t+\phi)\$, \$\phi\$ is the phase angle between \$V_{tot}(t)\$ and \$I_{tot}(t)\$ ...
1
vote
2answers
99 views

Peltier circuit design for TEC

I'm designing a TEC circuit with a Peltier element, LM35 as the sensor and Arduino uno as the controller. I simulated it with Proteus and to my knowledge it was working, I suppose. But when I tried to ...
1
vote
1answer
53 views

Output Radio Circuit Board to Speaker

I have a AM/FM radio board I found and am trying get playing through a small speaker. The other components were missing so I don't know how this connects to the rest of the system which had a CD ...
0
votes
1answer
78 views

Circuit help. I want a Voltage gain from 5 volts to 10 volts.

I need some circuit help.. I am trying to boost my voltage from a 5v source to a 10v output so I want a Gain of 2. I Ran the simulation and built the circuit exactly how it is shown in the figure ...
0
votes
1answer
60 views

How to invert a circuit

I have a door sensor that works when the door open. I need to use it for other purpose so when the door open the circuit turned off.. While the door closed the circuit should goes on. I want to link ...
3
votes
1answer
144 views

AC circuit with unusually placed transformer

Here's the circuit: simulate this circuit – Schematic created using CircuitLab $$I=2.25,0° mA$$ What's the $$n=N1/N2$$ of the transformer so that on R3 most power is dissipated. Power? ...
0
votes
0answers
35 views

AN-101 IC obsolete ? No description or design available

I have some of these ICs lying around over a decade, received as surplus from somebody. They are marked 'PROCON AN-101' Despite detailed search on internet, can not find pinout, description or any ...
1
vote
2answers
61 views

How to calculate the voltage across the load of this circuit

I have this rechargeable night lamp which I built it using the circuit which I got it over the internet.There is no problem with the night lamp but I just wanted study the working of the circuit but I ...
0
votes
1answer
28 views

AC steady state circuit analysis using mesh

I have attempted multiple tries into this circuit problem and I am getting no where. For this question I have to use mesh analysis to find \$V_x\$. \$V_x\$ is across the right branch containing the 3 ...
0
votes
4answers
51 views

Why does this circuit give different values for different methods

Is there a rule that I am missing? I need to find the resistance of this circuit: I seem to get different values depending on which way I take the resistors. Is there any rule I am missing when ...
1
vote
1answer
53 views

Finding Equivalent Resistance

The question asks to find the equivalent resistance of such a network of resistors. simulate this circuit – Schematic created using CircuitLab I have managed to simplify it down to the ...