Should I ground my amplifier? Answered

This needs a bit of background info. I found this amplifier a year ago in the streets, by the trash, and I took it with me cause I like to open up things and see what I could get (it was obviously broken). I opened it up, and started looking at the parts. The connections are old-school, first time seeing those. I noticed that one cable was not connected, so I took care of it, and tried to power it up. For my surprise it worked, and I had to secure the plug, which had only red and black (+ & - I guess). Fast forward to now, I heard or read that anything connected to a plug should have the ground as well, especially if it had something metal. The amplifier is made of metal on the sides. I'm giving it to my uncle, but I don't want to give him in a dangerous state, so, should I change the plug again and put one with the 3 wires? How or where do I connect the ground? (I saw one connected to a screw in the metal part once) And most important, why? Thanks a lot, sorry for length and for possible grammar or vocabulary mistakes. TL;DR: Found an amplifier without plug, should I put one with ground? How? Where? and Why? THANKS!! I've got answers saying that ground on audio systems are complicated and I've been reading but it's so confusing, and I don't understand it pretty well... THANKS IN ADVANCE TO ANYONE GIVING ME SOME INPUT, I REALLY APPRECIATE IT!! :D

Question by SuperPollo   |  last reply

Temperature stabilizer system with peltier battery

Hello everyone! I have a thesis to design a temperature stabilizing(controlling) system for solar cells.I need to use 12V Peltier battery and a simple pc fan.Any further help is appreciated.

Topic by UgurO   |  last reply

Can you help me with my mini E.M.P. generator design?

Hello everyone! I am currently planning on bulding a handheld E.M.P. generator (it's dangerous, I know, sorry) that is capable of killing a small devices (e.g. a small camera) at close range (<10cm). I got to the capacitor bank and wondered if 180J is enough for my needs? I also have some other questions (in no particular order): - What is the bare minimum to kill such devices? - Does it normally take 90 secs to charge a 90uF bank to 2kV (using a DC boost converter)? I have never designed a high voltage charging circuit before so I don't really know if I'm doing things right. - Is my capacitor configuration good enough or does it need tweaking (e.g. more voltage)? - How do I protect my circuitry from getting blasted by the coil? - Is a single pulse sufficient? - What kind of switch should I use for high voltage? - Should I use lithium-ion batteries for supplying power? - Should I make the frame of the device out of metal? - Should I be using a DC boost converter for charging capacitors? If not, suggestion? - Should my coil have a little or a lot of inductance? Again, I am fully aware this has "Darwin Award" written all over, sorry about that, but I think this is safer than guessing around. Thank you for reading this! Looking forward to your responds!

Topic by mr.derpinton   |  last reply

Recycle Nexus 7 2013 display module?

I once got my Nexus 7 (2013 version) broken and fixed with a screen replacement. ASUS gave me back the display. Good news is, only the touch part is dead, the LCD display is still good. Is there any way that I can reuse this part, as a side screen to desktop computer for instance? P.S: I'm using iMac at the office so it'd be great if the hack is applicable on Mac.

Question by zhangspievolgen   |  last reply

Gears for Servos and Steppers

Hey guys (and gals), I've been researching this a lot, but I still haven't the solution.  When you are working on a project and you need a gear for your stepper or servo, where do you acquire it?  For example I work a lot with TowerPro 996 servos, but I haven't found any third parties selling gears for them.   Same thing for motors.  If you are using a stepper motor, like a NEMA or something where do you find a gear that attaches to it? 

Topic by Deft Punk   |  last reply

help creating a biosensor prototype

I will attempt to be as concise as possible. That said, please bare with me if things are explained as well as they need to be, I am very new to this. Determined, but still a novice. I am conducting research as part of an effort to create a wearable prototype. Essentially, I need to combine a ppg heart rate monitor with a infrared thermometer (to measure skin temperature) and to have both devices maintain bluetooth capability. Any input in regards to this would be amazing.  More specifically, I am wondering if there are any DIY ppg heart rate monitor and/or infrared thermometer starter kits? Or resources that will assist with building these elements, aside from tutorials. I ask because it is a challenge to uncover all of the nuance and intricacies with electrical engineering and design without having a sufficient background.  For instance, it is clearly possible to add a bluetooth component to a heart rate monitor, but I am unsure if the two components (ppg hrm and infrared therm) must "talk" to each other while maintaining a bluetooth connection to a website or some other device.  If this is all as "simple" as building these devices separately and adding a bluetooth component to each of them, it would be greatly appreciated if you can provide a specific link to easy sources to obtain the components. I think I can follow along the tutorials, though there are still questions there.  Salud

Topic by ChrisU2   |  last reply

Arduino magnetic card reader with tape head

How can i make a arduino magnetic card reader with only a bare tape head without external circuitry 

Topic by atharva12   |  last reply

Using Xbox wireless controller on pc

I am wanting to use my wireless xbox controller from my xbox on my pc, I do not have a wireless receiver for my pc, however I do have a data cable for the controller, would this work as a substitute for a wireless receiver.

Topic by shotgunshane   |  last reply

Stepper motor

I have a small size sanyo denki 103 series stepper motor. I wanted to use it using L298 driver. What will be the connections  

Question by UsmanR1   |  last reply


Is a "group" a place to store things I want to keep for future reference?  How do I create a group?

Question by longlady   |  last reply

90 degree turn of a line follower robot

I want a line follower to follow this track and when it comes back to the start point i want it to take the path of the starting point again not the forward path and so on . ONLY BY USING LOGIC GATES ( no micro-controller, Arduino..etc )

Question by superdz   |  last reply

Is this a fuse or a resistor? Answered

I have been having difficulties with a PSU construction for a formerly battery driven (unknown amperage, 18 v ) electric drill and first needed help in identifying a part; picture included:  

Question by Goodhart   |  last reply

The notifications constipation may be over !!! maybe? Answered

After all this time of not getting notifications I just got a flood of all the past ones, its pretty funny like a major cork finally letting go.  So check to see if your emails have received something along the line of "you have 120 new comments" A big thank you to those who have been puzzling through this latest glitch. Here's hoping that this one is resolved for good.

Question by Vyger   |  last reply

very strange speaker amp problem?

I have two 5v speaker amps. One i made myself and another I got from my cousins junk box. Anyways, when I connect the speaker it has a very very loud buzzing. The strange part is when I touch almost any terminal in the circuit with my finger the buzzing stops and it plays normally with very little buzzing. The amp I made I have followed the circuit schematic exactly and triple checked everything. I have tried grounding the parts too but that didnt work so I know its not a grounding issue. Another thing, while I was making the amp I tested it and it did the same thing but it started working when a 10k resistor popped out of its place and was sticking straight up in the air, it was originally connected to ground. please help.

Question by fossilshark   |  last reply

problem with ethernet udp

Hi im try to set up a simple client server model that allows me to send strings between Python running on PC and the arduino over Ethernet. code of the server side software is: #include //Load Ethernet Library #include //Load the Udp Library #include //Load SPI Library float tempC; //Declare variable for Temp in C float temp; byte mac[] ={ 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED}; //Assign mac address IPAddress ip(192,168,0,252); //Assign the IP Adress unsigned int localPort = 80; // Assign a port to talk over char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; //dimensian a char array to hold our data packet String datReq; //String for our data int packetSize; //Size of the packet EthernetUDP Udp; // Create a UDP Object void setup() { Serial.begin(9600); //Initialize Serial Port Ethernet.begin( mac, ip); //Inialize the Ethernet Udp.begin(localPort); //Initialize Udp delay(1500); //delay } void loop() { packetSize =Udp.parsePacket(); //Reads the packet size       Serial.print(tempC); if(packetSize>0)  //if packetSize is >0, that means someone has sent a request {               , UDP_TX_PACKET_MAX_SIZE); //Read the data request             String datReq(packetBuffer); //Convert char array packetBuffer into a string called datReq if (datReq =="Temperature")  //Do the following if Temperature is requested     {       temp = analogRead(0); //read analog input on pin A0       tempC = temp * 5.0 * 100.0/1024.0; // ADC to celcius conversion       Udp.beginPacket(Udp.remoteIP(), Udp.remotePort()); //Initialize packet send       Udp.print(tempC); //Send the temperature data       Udp.endPacket(); //End the packet } }   memset(packetBuffer, 0, UDP_TX_PACKET_MAX_SIZE); //clear out the packetBuffer array } code python of the client is: from socket import * import time address = ('', 80) #define server IP and port client_socket =socket(AF_INET, SOCK_DGRAM) #Set up the Socket client_socket.settimeout(1) #Only wait 1 second for a response while(1):     data = "Temperature" #Set data request to Temperature     client_socket.sendto( data, address) #Send the data request     try:         rec_data, addr = client_socket.recvfrom(2048) #Read response from arduino         temp = float(rec_data) #Convert string rec_data to float temp         print "The Measured Temperature is ", temp, " degrees C." # Print the result     except:         pass     time.sleep(2) #delay before sending next command     print "" please any help when i run the programe nothing happen and i don't no why ???

Question by SoufianeG 

How would I go about making a basketball that deflates via remote control?

For a project, I'd like to make basketball that deflates when someone pushes a button on a remote. This is really just a proof of concept for a video, so if the mechanism impedes the ability to play, that's okay for now. Does anyone have any ideas on how to tackle this unusual challenge?

Question by AlfredoSG   |  last reply

How to interfacing cc2500 into pc?

Now, i am stuck in my project this state,the data is transfer to pc using cc2500 and pic,then transfer the data pc to to takw the data in pc,also i am using visual studio,but how to get the data in cc2500. please helb me  

Question by kumar manoj   |  last reply

Ubuntu for toughbook?

Ubuntu flavor that is best for Panasonic toughbook CF-30 MP3 core 2duo L9300 and ease of installation?

Question by halham   |  last reply

How do I fix my java code to print out the correct thing?

Hello I am working on homework and I am trying to figure out what is wrong with my code so that it will print correctly. Write a Java program that prompt the user for the day and month (both integers) of his or her birthday, and then prints the appropriate astrological sign. public class Horoscope { public static void main(String args [] ) { String birthday = System.console().readline("Enter your birthday, month then day."); float value = Float.parseFloat(birthday); if (month < 1 || month > 12) {   System.out.println("Invalid month please try again."); } else if (day < 1 || day > 31) {   System.out.println("Invalid day please try again."); } else if (month = 1 || month = 12) {    } else if (day >= 22 || day <= 19); {    System.out.println(birthday + "Capricorn");   } } }

Question by bubbles92   |  last reply

Internet won't work on my laptop (Windows 8) but says it's connected?

My internet on my Windows 8 laptop isn't working. Whenever I open a tab it says   He's dead, Jim! then under that it says Either Chrome ran out of memory or the process for the webpage was terminated for some other reason. To continue, reload or go to another page.   I've already tried looking for solutions but none of them work for Windows 8. Can someone else please help?

Question by fox_paw   |  last reply

how to turn off family safety without logging into the monitors user account?

Hey i'm bella, 16 year old girl gamer that only wants to play wizard101 but my dad installed family safety into my laptop that now wont let me do anything, and my dad is never here so I cant get the password for it, so how can I get family safety off my laptop or some how restart my laptop to get the program off it? please answer me.

Question by gamerchickquest   |  last reply

Resistors on the Bluetooth speaker!! Answered

I wanted to know why the resistors were used on the Bluetooth speaker and if I need them,  what size are they? 

Question by LASOUND   |  last reply

Arduino bluetooth control

So, I've been on a project where i am trying to use a generic bluetooth gamepad to control dc motors through a HC05 bluetooth module connected to an arduino. I have no idea on where to start. I did some research about it but there dosent seem to be much information thats appropriate for this project. here is what im using now: -ipega bluetooth controller -arduino mega 2560 -HC-05 bluetooth module

Topic by thomasmanman   |  last reply

LEDs on a costume?

I have never used LEDs on a costume before, my planned costume will have approximately 50 separate strands of lights on it, in two different colors.  The way the costume is designed, there is simply no place to hide 50 battery packs (20, maybe but not 50), is there a way to attach several strands of lights to one battery pack and still light up for several hours? I was planing on buying a long strip of LEDs that I could cut to length, what types of battery packs would I need to use?  Any instructions, videos or tutorials would be awesome.

Question by TishaC   |  last reply

How do I stop banner ads?

Question by rogandglo   |  last reply

Hi everyone, i need good low power amplifier ICs for speaker . Which IC can I choose?

There are requirements about amplifier IC for speaker :   - Sound quality must be good because I like non-lyrics musics and rock   - Very low crossover distortion and noise.   - Low power ( <30W)   - Output impedance 4Ω or 8Ω   - With bass booster I hope someone will answer ang give me a circuit diagram of this IC ( I need stereo, not mono or bridge ) Finally thanks a lots to people ! ( I'm not good at English, sorry )   

Question by Nikolai Petrenko   |  last reply

I'm a Pro member, Why can I NOT download ebooks?

The link attached to the "download PDF" gets me here : AccessDenied Access Denied C4AC3DC7F9FBC1FF cdonsQHcAVtDyx8ID0Mo8A+JkVqC/YcqVIwpTJO2sSB0WX3Vph7vnMXfBViIWZyv

Question by goldsmith0 

Can someone make a breadboard layout for this schematic? Answered

I already have a pulse detector module.. simple with LED and photodector.. It has 3 pins: VCC, GND and one ouput(from photodetector) as signal.. I want to amplify the signal using op amp LM324 i have the following resistors available: 10Ω、22Ω、47Ω、100Ω、150Ω、200Ω、220Ω、270Ω、330Ω、 470Ω、510Ω、680Ω、1KΩ、2KΩ、2.2KΩ、3.3KΩ、4.7KΩ、 5.1KΩ、6.8KΩ、10KΩ、20KΩ、47KΩ、51KΩ、68KΩ、100KΩ、 220KΩ、300KΩ、470KΩ、680KΩ、1M and following capacitors 50V 2.2UF 100V 10UF 50V 10UF 16V 100UF 16V 47UF 25V 33UF 50V 1UF 16V 220UF 50V 0.22UF 50V 4.7UF 50V 0.47UF 25V 22UF

Question by Rahul27   |  last reply

How can you program chip to detect motion using infrared or thermal? Answered

I'm making a Smart Pistol MK5 from the videogame Titanfall and I was thinking if I could use camera from gun to special glasses that could detect motion that uses infrared and/or thermal. My problem is how to code a chip to detect motion.

Question by EpicNickP   |  last reply

DC motor speed controller layout Answered

Alright so below is a quick picture i drew up of the circuit for an electric kayak idea i have. The drawing is just a rough mock up. I think I'm on the right track, but looking for somebody with more experience to double check it!   Really appreciate any help! Thank you! Below is the link to the PWM Speed Controller i plan to use:

Question by ScratchBuiltAircraft   |  last reply

230V AC to 12V 0.2A DC Answered

Could you guys please post a scheme for doing this thing? Thanks

Question by luky58527.   |  last reply

using TSOP4838 in anti-collision line follower

i want to use IR sensors with emitter part ( IR led ) - calibrated with an IC timer to give 38KHZ IR signal - mounted side by side - not face to face like the counter module - to the receiver part ( TSOP4838 ) which will turn on once something reflect the IR signal back to the receiver. [ the default is that IR signals will go straight forever without being seen by the receiver ]. I've followed the steps of a circuit using IR sensor in an object counter module it included transistors to be triggered instantly as described the problem is that it gives an instant pulse to trigger the 7-segment display. but in here i don't need it to be instant. how could i implement it to make the LED bright as long as i block the path [ not instantly ]. and to be off whenever there's no object in front of the robot

Question by superdz 

What is the difference between a 6v 80mA solar cell and a 6v 830mA solar cell?

What is the difference between a 6v 80mA solar cell and a 6v 830mA solar cell?I am trying to make a solar phone charger and need to know. Thanks!

Question by DELETED_MakerNinja   |  last reply

PCB fab lab questions? (and nixie tubes?) Answered

Now that I have a new oscilloscope (rigol DS1054Z), and have learned a LOT about programming and electronics while down at NASA langley for a research program (semi-intern), I feel like I should start working on a real project (other than my quadcopter), and was thinking about making a nixie tube clock. I would like to make it from scratch of my own design as I feel one learned the most about electronics by not using other's designs. However, I do not have the resources or time to bother trying to etch my own PCB. I attempted that before and was not able to get usable results. What kind of costs am I looking at if I locate a relatively local company for the job? I hate calling people and companies, but I suppose that is still the most practical way to figure out what I need to do and place an order, I don't know. Economies of scale is a great thing, makes things in bulk production cheap! However, would the costs of ordering one or 2 PCBs be non-economical and/or non-practical? Should I consider many smaller projects and stuff to be created on a breakout board? I hate messy, sloppy protoboard, it is just nasty, though easy for non-high-density boards. however, I would love to hear the opinions of others for these things. When dealing with nixie tubes, are sockets for the 1N-14 avalible? A lot of the new old stocks seem to have very thin and long legs, almost as if they are meant for through hole soldering directly onto a PCB like capacitors and resistors. I would prefer a socketed tube to make replacing them quicker and easier. 

Question by -max-   |  last reply

what is the function of a pulley in a elevator?

May i know can pulley be substituted with anything else as efficient?

Question by anku218   |  last reply

Car security ?

So I was wondering if anyone would have any knowledge on car alarms i want to make a app that will send me a notification whenever my car is messed with using a modified viper security system 

Question by gavinh6 

What to do with this? Answered

I have this LCD and another with 41 pin connection, no main board on them only a small control one. Any project ideea is welcomed, and if you have any tips and trick how to do it .

Question by theVader75   |  last reply

Arduino to Android Sensor result (Flood Alert)

Can i connect my arduino to android via my own app ( project)__ flood alert 1. app must be downloaded from play store 2. send and receive data must use internet 3. target 200 persons 4. app for read water level in app connected to internet. 5. app can trigger alarm if safety water level is exceeded.                                   looks more like this(pic) pls help me...

Question by harek   |  last reply

DC motor speed controller questions Answered

In the early stages of planning an electric kayak build. Im Brainstorming ideas on how the propulsion system will work and have a few questions when it comes to DC motor speed controllers.  First off i plan on using a 100W 24v DC motor from a old electric scooter.  Not sure on the type of battery yet but it will be a 24V Now i am fairly experienced with RC Aircraft electronics, but this appears to be a different ball game! After some research it appears i want a PWM Speed controller that can handle at least 24V.   Amps wise i think i want at least 4 Amps. (Assuming my calculation was correct based off the Watts and Volts )  So this is basically more of a "am i barking up the right tree" question!   As i said earlier this is just early planning stages of the build and i want to make sure i don't make any silly mistakes!  Any help is greatly appreciated! Thanks!

Question by ScratchBuiltAircraft   |  last reply

110AC to 140DC? Answered

I've got a 140VDC motor from an old garage door opener.  I want to use the motor for another purpose.  The original controller board is fried.  Will a bridge rectifier that can handle 110AC over power the motor?

Question by frasej   |  last reply

What is the microcontroller that can i use to make humanoid robot ? Answered

I want to know what the microcontroller that can i use and i wish if it is arduino because it will be easier for me to get it .

Question by marwan97   |  last reply

How do i have his texts sent to me?

I want my boyfriends texts sent to me but I don't have access to his phone. Help!

Question by raedubya   |  last reply

Carbon Fibre Flywheel (for energy storage)

I'd like to build a flywheel but I'm not sure what I need to know before i start, Is it difficult to do? Is it possible to accomplish with off the shelf parts? Any help at all would be appreciated greatly.

Topic by nuncoop   |  last reply

Velleman Sound to Light module LEDs always on.

I  have made the velleman sound to light project: the LEDs are supposed to turn off when there is no sound and go bright when there are loud sounds. Mine are bright all the time. I first tried the kit using my own blue LEDs instead of the red ones supplied, these worked for a time then they just stated to give a VERY small amount of light. I switched to the red ones and now they are on high all the time. I also accidentaly connected R3 with C4 (see PDF). C1 and R2 are also connected by solder, im not sure if it should be like that, I also kinda damaged the C1 connection hole as I partially burnt it with my soldering iron D:.  Could any of these issues be the reason why my kit inst working? I have attached pictures of my board Many thanks, Rushmoore :)

Topic by Rushmoore   |  last reply

[Arduino] Problem connection Bluetooth

Hi all, A while ago I got a HC06 bluetooth module. In the beginning everything worked OK, but now some problems have appeared. Pairing in Android works fine, as well as with my laptop. The problem arises when connecting my phone (Google Android 4.2 with Bluetooth 2.0 + EDR) to the device. BlueTooth Serial Controller 16 seems the only working app, but I would like to use my own application, based on the code described here Also other apps like BlueSerial Beta and Bluetooth ssp pro do not work. Does anyone have a clue how to solve this problem? Many thanks in advance. Regards, Zytro

Topic by zytro   |  last reply

DIY phone headset to computer plug?? Answered

I would like to make one of these. It is to connect to the headset port in my phone to record some greeting that I saved on my computer It only needs to connect the computer speaker to the phones mic. I need to know the pinouts of both connectors and what to connect together Thanks

Question by FarmerKJS   |  last reply

How to connect LED light fixture and Peltier cooler in same DC power supply without reducing their capcity? Answered

I have a atx power supply which i have converted to 12 V DC power source,  current rated as 22 amps.  I have connected a LED light appliance(90W) and a peltier cooler(62.2 W, Umax =15.4 v, Imax = 7 amp,1.7 Ohm resistance ) in parallel connection. But when i attached both of them to the PSU , my LED lights dim. What is the reason for this ??  I have tried with other combination that is peltier cooler and CPU cooler fan and find that the fan is not operating in same rpm when it runs as a sigle device with PSU. Is Peltier cooler make the circuit short??

Question by AdnanN1   |  last reply

Solar Cell Phone Chargers

Solar Cell Phone Chargers Since we all walk many hours in the sun each day, does anyone have knowledge of a functional solar charger for phones or cameras?

Topic by weijing3333   |  last reply