LEDs - Under-volt, over-amped?

My issue: Have multiple LED drivers, (high power LED instructable) and connected the wrong one. The LEDs are not dead. My LEDs are rated at 9-12v, 950mA and I have sets of 4 in series hooked up to a 36v power supply. The driver I used has a .3ohm resistor on it. so it's putting out ~1.3A The LEDs should have burned up. Since the driver eats up a little of the voltage, each LED is getting ~8.75v. Is this why they haven't burned up? Thanks!!

Topic by thestip   |  last reply


Compact bubble gun mechanism?

My 7yo was begging for a bubble gun, and I promised I'd 3d print him one.  To my surprise, there are very few 3d printable bubble machine designs around, and none that match what he wants.  (He wants it to have a handle and trigger like a handgun.)  So, I suppose I'll be designing one. . . (FYI - My parts bin has plenty of fans and motors and even small liquid pumps and I am competent at 3d design. ) My challenge is that the basic rotating disk method of wetting the bubble hoops is both too bulky for a handgun-style bubble shooter, and is highly spill-able. I see online there are numerous toy bubble guns that look like what I want and appear to be much less spill-able.  However, I can't figure out from the pictures how they work, beyond that there is a pump that sends bubble solution to above the hoop and a funnel to route the excess back into the container.  How does the bubble solution get swiped across the hoop reliably? (And, yes, I know it would be easier and cheaper to just buy one.  That's not the point.)

Topic by SvdSinner   |  last reply


Arduino | Run 2 Function at the same time.

Hi , i wanna ask about 2 function which is Ultrasonic and Heat that run at the same time  , For me , i just got Heat running as i want but the Ultrasonic doesn't trigger the buzzer if object (Laptop) 30cm away from the ultrasonic. I've been trying since last week but the result is still the same ;'( Btw here is the code , i've seperate it to 2 function which is Ultrasonic and Heat.  i hope u guys can guide me which part should i change or Add. Thanks in advance ;) //*********************************** #include #define trigPin 6    //trigPin #define echoPin 7    //echoPin LiquidCrystal lcd(12,11,5,4,3,2); int tempPin = A1;   // the output pin of LM35 int fan = 10;       // the pin where fan is int led = 9;        // led pin int temp; int tempMin = 35;   // the temperature to start the fan int tempMax = 70;   // the maximum temperature when fan is at 100% int fanSpeed; int fanLCD; int duration, distance; int buzzer = LOW; void setup() {   Serial.begin (9600);        //Baud rate   pinMode (trigPin, OUTPUT);  //trig pin as output   pinMode (echoPin, INPUT);   //echo pin as input   pinMode (13, OUTPUT);       //Buzzer pin as output   pinMode(fan, OUTPUT);   pinMode(led, OUTPUT);   pinMode(tempPin, INPUT);   lcd.begin(16,2);   } void ultrasonic() {   digitalWrite (trigPin, HIGH);   delayMicroseconds (1000);   digitalWrite (trigPin, LOW);   duration = pulseIn (echoPin, HIGH);   distance = (duration/2) / 29.1;   if (distance > 30)   {     Serial.print(distance);     Serial.println(" cm");     digitalWrite (13, HIGH);   }   else   {     Serial.println (distance);     Serial.println ( "cm");     digitalWrite (13, LOW);   } } void heat() {   temp = readTemp();     // get the temperature   if(temp < tempMin) {   // if temp is lower than minimum temp     fanSpeed = 0;      // fan is not spinning     digitalWrite(fan, LOW);         }   if((temp >= tempMin) && (temp <= tempMax)) {  // if temperature is higher than minimum temp     fanSpeed = map(temp, tempMin, tempMax, 32, 255); // the actual speed of fan     fanLCD = map(temp, tempMin, tempMax, 0, 100);  // speed of fan to display on LCD     analogWrite(fan, fanSpeed);  // spin the fan at the fanSpeed speed   }   if(temp > tempMax) {        // if temp is higher than tempMax     digitalWrite(led, HIGH);  // turn on led   }   else {                    // else turn of led     digitalWrite(led, LOW);   }   lcd.print("TEMP: ");   lcd.print(temp);      // display the temperature   lcd.print("C ");   lcd.setCursor(0,1);   // move cursor to next line   lcd.print("FANS: ");   lcd.print(fanLCD);    // display the fan speed   lcd.print("%");   delay(200);   lcd.clear();   } float readTemp() {  // get the temperature and convert it to celsius   temp = analogRead(tempPin);   return temp * 0.48828125; } void loop() {    ultrasonic();   heat(); } //***********************************

Topic by Melromeo   |  last reply


Does Electrical Tape Have A Use?

Hello, I was wondering if black electrical tape actually had a use? I ask because it doesn't seem to really stick to anything for very long. It eventually becomes un-done from what it was wrapped around and then leaves a sticky residue behind. Am I not using it properly or not using it the way it was intended? Does anybody else have this problem? (I have the same problem with that Saran clear plastic wrap stuff, it doesn't stick to anything but itself. So, it could be user error.) Thanks J

Topic by sdtacoma   |  last reply


Arduino Strobe Controller for bike lights

Hey guys, this is where I am selling kits to build my ultimate Arduino strobe controller system. Read about the whole project here! Bare PCB alone (comes with a BOM for population): $8 Complete Kit with everything but the light modules and battery charger: $50 These prices include shipping within the continental USA. If you're in the US, I will include two 18650 Li-ion cells with the kit. If you are outside the USA, shipping will cost more but I can't ship the batteries, which works out so the price will be the same! You will still need to acquire a charger and supplies for building your light modules, no matter where you live. PM me if you are interested in buying a kit!

Topic by thecheese429 


Arduino 12V Car-alarm with PIR sensor and remote control - expertise needed. :-)

Hi all, This is my first "big" Arduino project and my first fritzing, so please bear with me. :-) Goal: - Build the cheapest possible car alarm system with a loud siren - It should be possible to activate/deactivate the alarm with a remote control. - The alarm will once activated, sense any motion in the car (if someone breaks a window and tries to steal anything) and set of the alarm. - The system should not drain the car battery so it should draw a minimum of power. I've managed to build the first few things, but some vital steps are still needed and I hope you can help me sort these out. Components used so far: Arduino Pro Mini - TIP122 transistor - 2.2KOhm resistor - 1N4002 diode - Mini piezo siren (I used a 107dB siren with an operating voltage of 6-15Vdc and current consumption of 140mA) - Breadboard - Lots of wires I'm currently waiting for my PIR sensor to arrive together with the RF receiver/transmitter module, so for now I've added a basic switch to act as the PIR sensor and another for the RF module (activate/deactivate). The components I'm waiting for are: - An RF module that I need to order once i find the right one. - http://www.ebay.com/itm/261041100836?_trksid=p2060... Questions that still remain and that I hope you can help me with: 1. The arduino should be powered by the cars 12V battery, however I've read that the car battery must be regulated as it delivers anywhere from 12 - 16V. I could connect it directly to RAW but in case the battery peaks above 16V i risk damaging the Arduino. I'm very unsure as to how I do this regulating best? One option could be to buy a "DC-DC step down converter - 4-35Vdc > 1,23-30Vdc" and set it to 5V, but maybe a more simple and/or cheaper solution exists? 2. Since the power consumption should be kept to a minimum, I plan to add the RF before the step down converter so the powering of the regulator (step down converter?) only happens if the alarm is activated from the remote. First question is: can I use a TIP120 for this and simply connect the RF to base, and the regulator to the collector? Second: In this case, the Arduino will be powered off the hard way by cutting power when deactivating the alarm from the remote - can the arduino take that in the long run? and finally, the RF receiver needs to get its power from somewhere, so what can I do here - is the best thing to use a 12V RF module instead of the Arduino 5V RF module or can this be solved some other way? 3. Any good ideas for minimizing power consumption? 4. Anything I can do to further improve the design? :-) I'll update this post as I progress with the project including a more detailed step guide to how to implement this and the source code I'm using. Instructables arduino posts and commets have helped me a lot during over the past few weeks working with Arduino so I hope you can help me reach the finish line with this project. Br. Jakob

Topic by Zyb3r   |  last reply


Dual energy generation with magnetic Seesaw system and gravity with the help of 3 volt toy motor

This technology is based on  a Seesaw system and magnetic repelling principle Linear motion  .We can generate electricity with very little force with the help of this technology.This will be a radical step in the field of energy generation. In this technology there will be a balance system and two heavy weight magnets(high strength NEODYMIUM MAGNETS) will be attached with each side of this balance system as per diagram. As per diagram there will be two moving weights and these moving weights will move on tracks.These tracks will be fixed at the angle of 8 to 10 degree. Two magnets will be attached on the front side of these moving weights and these magnets will have similar polarity with the magnets of balance system. These moving weights will be attached with two gear boxes and these gear boxes will be attached with two generators. HOW THIS TECH WILL WORK? When one side heavy weight magnet of balance system will be pressed with the help of any kind of external force then this side will come down and repel its side moving weight due to equal polarity of magnets.due to repelling the moving weight will move forward .but when the heavy weight magnet will move upward then this moving weight will move backward due to gravity to get its position back. in this way this moving weight will work to run a gear box and this gear box will work to start a generator to generate energy. This balance system will also work to pass through their side copper coil due to linear movement and in this way this technology will generate Dual energy. WE will take very high strength NEODYMIUM magnets  for balance system. I would like to insist on some following points (1) The balance system will be attached with 'L' form crank with external PRESSING source. (2) The moving weights will also be attached with 'L' form crank with gear boxes. (3) Each side magnet of balance system will work one by one .When one side magnet will come down the another side magnet will move up .These magnets will come down and move up one by one to repel their side moving weight. (4) We can take as much weight as we can of these magnets of balance system .(500 kilogram to 1000 Kilogram or more) to pass through the heavy coils having 100000 turns or more.  (5) External source of pressing this balance system could be anything such as pressing with foot  or solar cell. WE WILL NEED ONLY 3 VOLT EXTERNAL ENERGY TO PRESS THIS BALANCE SYSTEM  AND GENERATE MORE AND MORE ENERGY.

Topic by vikram_gupta11 


Do I need to use a metal box for an outlet?

I'm making a concrete art piece and want to insert an electrical outlet inside it.  Is it okay if I embed the outlet in the concrete or is there a reason I need to use the metal outlet box like is used in the wall?

Topic by mazelady   |  last reply


Disecting Strobe FX

Hello all you LED inventors I have a few questions for you....One of My Favorite LED toys ever is the Stobe FX LED wand(which they dont make anymore) they used to be ten bux each NOW they are like 75 a pair on EBAY....What I would like to do if possible is collaborate with some one that knows electronics and might beable to hel me recreate the effect but Modify it for durability...The wand has 30 mode and 2 buttons one turns it one and one changes the color 15 original modes but if you hold the CHANGE button it send orignal into slowest too fastest mode...I have some "dead" soliders that I can use for "POI" like to practice my FIRE arts.. Neighborly Yours Dave myspace.com/hrdcr4lf

Topic by hrdcr4lf   |  last reply


Board with NFC and WiFi

I'm looking for a board (for the moment a development board would be the best solution as I am prototyping) with NFC and WiFi integrated. I saw that Arduino should launch one with NFC, Wifi and Bluetooth, the board is called Primo. I can't find anything else and Arduino can't announced a date for the launch. For now I'm working with a NFC reader and the Arduino WiFi Board both mounted on a separate Arduino Uno because the two boards are incompatible. Any idea ? Thanks Alizée

Topic by AlizéeG   |  last reply


How to wire a switch

Hi I would like to know how this switch should be wired up. I am using it on a drill press. It has 2 relays 1/ nc zb2-be102 2/ no zb2-be101. Any help would be much appreciated. Thanks ratjack

Topic by ratjack   |  last reply


Control DC Motor with a L298N H-Bridge with 24V

Hello everyone, I bought this module with a L298N H-Bridge inside: https://cdn3.bigcommerce.com/s-vt19phz/product_images/uploaded_images/l298n-motor-driver-from-tronixlabs-australia.png Now I want to control a 24V DC motor with an incoming PWM 488 Hz signal from an external converter. I don't want an arduino or something else to control it. Just from this pwm signal. How do I connect it? I use a 24V power supply.

Topic by julianpe   |  last reply


Energy wheel

This Idea is based on Magnetic Repulsion and Kinetic force. According to diagram there will be a  Wheel and a magnet(1) will be attached with this wheel. There will be a balance system(seesaw system) and two magnets(2no.magnet and 3no. magnet) will be attached with this balance system . when 1 magnet will repel 2 no.magnet then the 2 no.magnet will move upward and due to this movement the 3 no. magnet will come down and will work to repel 1 no. magnet and wheel will start to rotate. when 1 no. magnet will again repel 2 no.magnet after a rotation then the 3 no. magnet will again work to repel the 1 no.magnet. In this way the wheel will rotate again and again.The magnetic strength of 1 no. magnet will be high than 2 no. and magnetic strength of 3 no. magnet will be high than 1 no. magnet. I want to develop this technology.

Topic by vikram_gupta11   |  last reply


Making Diy Ring Light. Help?

Ok at the moment i'm working on a Diy Ring Light.   I will try to be as detailed as possible.   The light source i'm using is from an old LED light box that has over 204 leds in a array  17x12 matrix  I am using a Old circle fan outer shell for the ring shape and i already made the outer casing. My problem is i am trying to wire these leds off of the matrix and in separate rows.  My plan is wire these leds in a circle and connect the ends to the LED light box controller.  Basically take the box led shape and make it into a circle.   At the moment the leds are attached to the board.  I have desoldered all of them almost and i have figured out the positive led and negative led.    As long as i wire the positive leds in a row and negative in its own row with paper clips and then connect it back up to the positive wire and negative wire on the controller i should have it working? Is there something else i need to do?   It will be powered by the wall because the controller has its own dc input and i have the correct power supply for it.       I will provide pictures if needed.   i hope this is enough info to help you guys help me.   Thanks.

Topic by AustinS83   |  last reply


Microwave Transformer To EMP

Hello, my question is simple. If I connect about 3v to a microwave transformer and then to a coil, would it make a efficient EMP wave (shutoff a calculator). I know that I can use a disposable camera, I just am learning different ways to do it. (Sorry for the pic, done with my phone haha)

Topic by Skydazz   |  last reply


PIC18LF4680 microcontroller and usb ttl for usart / serial data

Hi everyone. I want to know if it's possible to connect a ttl device directly to my PIC18LF4680 for serial communication via USART . I can connect the ttl device directly to my Arduino Uno without issues. The ttl  device has 6 pins (dtr , rxd , txd , vcc(3.3v or 5v) , cts, gnd) . I have two different codes snippets below that perform USART communication. * Version one(I) utilizes the "usart.h" peripheral library. * Version two(II) uses "TXREG" and "RCREG" for sending and receiving data. Both versions run well in my virtual environment (Proteus 8 Professional), but not in the real world environment. Am I missing a step? Do I need a special library? Or is it not possible with this chip? VERSION (I)   ------------------------ #include "fuses.h" #include #include #include #include void main(void) {         TRISB = 0x00;     OSCCON = 0x76;          // 8mhz (0111 0110)          LATBbits.LATB4 = 0;      LATBbits.LATB1 = 0;      LATBbits.LATB0 = 0;          unsigned char txt1[] = "Hello World \r\n";     unsigned char txt2[] = "Enter a number.... \r\n";         CloseUSART();         OpenUSART(USART_TX_INT_OFF &             USART_RX_INT_OFF &             USART_ASYNCH_MODE &             USART_EIGHT_BIT &             USART_CONT_RX &             USART_BRGH_HIGH &             USART_ADDEN_OFF ,             52);             for(int x=0;x<=20;x++){__delay_ms(50);}         // write/send intro to PC         while(BusyUSART());     putsUSART((char *)txt1);         for(int x=0;x<20;x++){__delay_ms(50);}         while(BusyUSART());     putsUSART((char *)txt2);             for(int x=0;x<20;x++){__delay_ms(50);}             while(1){         sdata = ReadUSART();                 switch(sdata){             case '1':                 LATBbits.LATB4 = 1;                  LATBbits.LATB1 = 0;                  LATBbits.LATB0 = 0;              break;                         case '2':                 LATBbits.LATB4 = 0;                 LATBbits.LATB1 = 1;                  LATBbits.LATB0 = 0;                             break;                         case '3':                 LATBbits.LATB4 = 0;                  LATBbits.LATB1 = 0;                  LATBbits.LATB0 = 1;              break;                                     default:                 LATBbits.LATB4 = 0;                 LATBbits.LATB1 = 0;                 LATBbits.LATB0 = 0;              break;         }     }     } -------------------------------------------- VERSION (II) --------------------------- #include "fuses.h" #include #include #include #define STRLEN 12 volatile unsigned char t; volatile unsigned char rcindex; volatile unsigned char rcbuf[STRLEN]; void USART_init(void){         TXSTAbits.TXEN = 1;     // enable transmitter     TXSTAbits.BRGH = 1;     // high baud rate mode     RCSTAbits.CREN = 1;     // enable continous receiving     // configure I/O pins     TRISCbits.TRISC7 = 1;     // RX pin is input     TRISCbits.TRISC6 = 1;     // TX pin is input (automatically configured)     SPBRG = 52;                PIE1bits.RCIE = 1;      // enable USART receive interrupt     RCSTAbits.SPEN = 1;     // enable USART         } void USART_putc(unsigned char c) {     while (!TXSTAbits.TRMT); // wait until transmit shift register is empty     TXREG = c;               // write character to TXREG and start transmission } void USART_puts(unsigned char *s) {     while (*s)     {         USART_putc(*s);     // send character pointed to by s         s++;                // increase pointer location to the next character     } } void main(void) {         OSCCON = 0x76;          // 8mhz (0111 0110)         USART_init();         USART_puts("Init complete! \n");     INTCONbits.PEIE = 1;    // enable peripheral interrupts     INTCONbits.GIE = 1;     // enable interrupts     while(1)     {     }     } void interrupt ISR(void) {     if (PIR1bits.RCIF)  // check if receive interrupt has fired     {         t = RCREG;      // read received character to buffer         // check if received character is not new line character         // and that maximum string length has not been reached         if ( (t != '\n') && (rcindex < STRLEN) )         {             rcbuf[rcindex] = t; // append received character to string             rcindex++;          // increment string index         }         else         {             rcindex = 0;        // reset string index             USART_puts(rcbuf);  // echo received string         }         PIR1bits.RCIF = 0;      // reset receive interrupt flag     } } ------------------------------------------------------------ Any and all help is appreciated. Thanks!

Topic by newbie14   |  last reply


41 LED Flasher Circuit using 555 IC

Ok I've managed to get the single LED working but not the rest what am I doing wrong ????????

Topic by TattooedJudge   |  last reply


How to connect my arduino uno to Internet to connect to MYSQL

Hi - I have arduino uno card which has a light sensor. I would want to transfer the light readings to MySQL database. How do I do it? I can write a sketch that can connect to MySQL and insert the data and upload the same to arduino card. But how will my ardino card connect to MySQL. Can you help me here as I am beginner to these topics? Regards, Harish

Topic by harishkompelh   |  last reply


ESP8266 + NRF24L01 + Arduino system?

Hi everyone, So, I'm pretty new to the esp8266, but have some experience with arduino (I'm certainly no master however). I'm working on a project that uses an esp8266 and a nrf24l01 radio module to transmit small packets of data to a 'base' module that is an arduino and another nrf24l01. I'm having some difficulties figuring out how to use the nrf24l01 with the esp8266, so I was wondering if anyone knows of any good libraries or tutorials or anything that might help me. I don't know any Lua at all, so it would need to run through the arduino ide, that's what I've used so far to program the esp8266. Any help at all would be greatly appreciated and I can try to answer any questions you might have. Oh, and it would be great if you could explain stuff in really simple terms, I'm still in highschool and don't have a very expansive technical vocabulary  :D Thank you  ~Dudes

Topic by dudes   |  last reply


Possible project with 433Mhz RF Transmitter + Receiver Module Link Using multiple analog sensors

Is it possible to send multiple sensor readings via through a 433Mhz RF Transmitter + Receiver Module Link?..Meaning, assume that I have a three Flex sensors on the transmitter side and three servos on the receiver side. I have the project almost complete however I would like to make it wireless with these rf modules. When you bend a flex sensor its corresponding servo motor will turn depending on how far the sensor is bent. I do not know if this is possible using these modules since there are multiple flex sensors and they are analog (I'm not sure if analog is the correct term but what I mean is since the sensors will output an array of values I don't know if it will work since its not digital) If anyone knows if this is possible please let me know and also if you can I would need help with the code, I have never made anything wireless before but it seams really neat. Thanks to all those who reply!

Topic by Daniel Quintana   |  last reply


Spa Controller Modification utilising Microcontroller Remote Station

Hi All, I'm looking at modifying our existing Spa controls with a Touch screen system that combines the functionality of the radio remote for the Spa controller & the remote control panel for the Spa heater. I also want it to be able to run the Sonos software and possibly do lighting control down the track. I would like to leave the existing water proof remote operational if possible but that assumes I can get the new 434MHz module in the microcontroller talking to the existing Rx in the Spa Controller and dont have to replace it. Im interested in any comments particularly as which mini computer to use. Price is a concern of course by function is more important. I havent worked out how to power it yet as there is no easy solution without nearby power points or network ports for PoE. I may perhaps go solar but not sure yet. It may be easier to run a cable for somewhere. Any insights much appreciated...

Topic by BrettB55 


Transistor Trouble

Hi there, I have been working on controlling a large toy car with a wireless receiver from a smaller toy car, the motors I need to control are rated for 9V but the receiver only outputs 3V, reversing polarity to reverse the motor. I made this schematic using transistors to handle the voltage, but when I built the circuit the transistors began to heat up and there was no output. I am not sure why this is happening, so any help would be greatly appreciated. Thanks, Daniel

Topic by daniel12354   |  last reply


Lighthouse pulsing light

Hi all - I am building a wooden model lighthouse, it will stand 5 feet tall and become my driveway landmark. I have been searching for a good light circuit, a non-LED version, preferably using 120v AC. I would like the light to just do a slow flash or pulse and haven't found a circuit anywhere. I did find one SCR simple circuit using a high rated capacitor, but I am looking for more options. I have a coloured halogen which should do the job well enough. So have any of you brainiacs come across any circuits close to this description - thank you for reading / responding. Bill

Topic by bstacy37   |  last reply


Selection of presence sensor

Hi guys. For one of my university projects I need to detect the presence of a person in the shower. In order to do that what I have in mind is use a proximity sensor. If the target is in a distance range (let's say 20 to 50 cm) It will assume that the person is in the shower when the distance measure is no longer in this range then it will mean that the person left the shower. I need to detect all the time of the person in the shower (meaning when he/she gets in and then out). I have read a lot of info and forums to properly choose the type of sensor. However I still don't have a clear answer. About the Ultrasonic proximity sensors I know that they are cheap and more accurate by it can be affected by Temperature, humidity and some ambient noise, all of them which happen in a shower. The other option an Infrared one gets affected by lightning conditions and the surface of the target. The last option I checked is a PIR sensor I know it senses Temperature of the target, but I don't know if it will be affected by the running hot water and also is more expensive. In general, I don't know how the running hot water will affect the detection of the person in shower. Also,so again I don't know how this will work. Sorry for the huge amount of  questions, I am a little bit confuse with all the factors to have in mind. I am hoping someone out there can help a lost newbie like me and give me a suggestion. Thanks a lot :)

Topic by mcamiea   |  last reply


Raspberry Pi 3 Vs UDOO Neo

Which is a better development board, in terms of automation, robotic and server function?  I plan to build a mobile-operated generic wireless controller that gathered data and also programmable in terms of control. I already drop by to other forums and still undecided. I don't consider a development board that so powerful. What I consider is the practicality, suitability, and compatibility. I appreciate your response and I want to know your ideas about this! Thanks and God bless!

Topic by ephtermulo 


Speed controlled industrial fan

Hi all, For an installation I need a speed controlled fan that I can control via a microcontroller. Is there any industrial fan that you know that allow to be controlled with eletrical signals rather than the usual manual control? thanks a lot!

Topic by amicoleo   |  last reply


Old UPS transformers: Any uses?

Does anyone know of a use for those massive transformers found in dead UPS's? Please don't post replies that include "door stop" or "recycle them" because those are obvious replies when you have no answer to my question. *SMILE* I have not tried but if the "secondary" for those that is the 110v output to the plugs were hooked to 110, do the original primaries become low voltage ac secondaries? (~12v) I have accumulated about 6 of these and would like to find an electronic use for them before resorting to recycle.  I have no doors that need propped open. Thanks.

Topic by stuffdone   |  last reply


running a camera and wireless station from batteries

Im thinking of setting up cameras away from my house and need advice on the power. basically they will be mounted on poles down fields from the house. what i plan on having is a network camera setup with the Ubiquiti wireless points (https://www.ubnt.com/airmax/nanostationm/). these will form a bridge of 2 or 3 cameras and the cameras will be connected to each, with one of the wireless points mounted on the top of the house to connect to.  what i cant figure out is the power. i would like to run a power cable down the field sometime but this will be costly and i want to try this out to make sure it works. i know deep cycle batteries would be best but i cant join the rest together. i know there will be a POE connecting into the wireless box and this will be split, so how would i join this to the battery, as would a converter be needed or any other suggestions would help. thanks!

Topic by ChrisD319   |  last reply


Passive mixers, I don't undertand why the resistor/capacitor

Hi, when I was young, our teacher show us a passive mixer, each input had only one green capacitor in series for each input, it was not electrolytic but ceramic or polyester, it sounded so good for just being there 1 simple component per channel. Now taking a look at google, can see that the most passive mixers, uses resistors to isolate sources, with values since 10k to even 100K. Other schematics shows a resistor and capacitor in series (see image below) what does that capacitor? and why some schematics only has a simple resistor? is it easy to calculate its ohm value?. Is it better using this configuration supposing that the source is weak (coming from cellphone 3.5 mini jack or RCA) and this mixer targets the signals to a pre amp? So I need to from weak sources like iphone, dvd, any RCA output, etc... anybody know whats the best to use in this case? Thanks so much. Should I put a resistor as minimum as possible? I undertstand that a resistor there, in the input, will reduce the volume input, and I dont want to do that, so can I simple connect everything direct? or the resistor isolates the inputs, otherwise it will sound ugly? I am very confused, why the resistor? why I have seen resistors from some ohms to 2km and even a lot more, 50k, 100k. I want to mix two weak sources, as a signal coming from a walkman and cd player, or cell phone, etc, so whats the law for not reduce signal intensity and mix everything well? all channels will come in into a pre amp IC.

Topic by destrip   |  last reply


Led Pool Lights How/Ideas???

I want to make some underwater LED lights. Any ideas on DIY? thanks

Topic by R4fo   |  last reply


Induction heater 2.0

Some might have already tried my first induction heater, which was more a proof of concept than a modern device. Although I like to keep things simple where possible I want to upgrade my heater to a fully electronic version running on mains power. This time the base concept is to use a cheap induction cooktop for the control and power source. After using a few already as a communication device I realised it is a costly way of producing smoke signs but I am getting on the right track with the design now. So my obvious questions are: 1. Did actually anyone ever built my current induction heater and if so, can you provide some nice pics? 2. If you were interested in a hobby induction heater, what would like to do with it?     E.g: Just for curiosity on how it works, heat treatment of punches, chisels and similar,     heat treating knifes or even swords, sheet metal work.... 3. What would like to have included?     E.g: Water cooling for continous use, air cooling (mostly for smaller and quick jobs), exchangable coils,     additional micro controller for temp, water and remote control (foot panel or similar)... 4. Do you require a fully shielded version to avoid interference? 5. If you are based in AU (preferable VIC): Would you be able to donate me faulty (partially or fully) or working induction cooktops,     for example discarded units with broken glass tops?     Would you able to donate me copper tubing OD8mm or less? Leftovers from pluming installations, old LPS systems or similar?     Prefered lenght 1m or longer as the coils need quite a few turns... :(     Each donor will of course be listed in the Instructable unless you prefer to remain unnamed. Let me know what you think because this time I am not just building for myself, this time it is for you!

Topic by Downunder35m   |  last reply


suggestions for retrofitting a late1970's portble cassette player/radio

Hi, I was given a late1970's portble cassette player/radio. the electronics are dead. but the body is in very good condition. It would be cool to retrofit it as a portable amp to connect to my phone or mp3 player I want to disembowel the machine and then fill it with an amp and lithium ion battery pack. it's a bit larger than a 6 pack of beer can any point me in the direction of some instructables or sites with some info? I'm thinking of buying a small amp kit from aliexpress. thanks

Topic by altomic   |  last reply


Wanted: Desktop PC's

I'm looking for free working desktop computers. It does not matter the specs or age. Just as long as it works. You can ship it if you are not nearby. I'm located In Erie PA. Thanks - Jadyn. 

Topic by Jadyn Langer   |  last reply


New to LEDs, need to wire lots of them

I've never worked with LED lights before.  I'm putting on a show and I want to have lots of little points of light in space in a dark theater.  I'm talking hundreds of them.  I considered fiber optics, but that started looking way too expensive.  Is it possible with LEDs?  Is it expensive?  How to I learn how to do it?

Topic by CameronS56   |  last reply


Human Detector

I'm trying to come up with a small, cheap, simple circuit that will detect a human. I plan to use a grid of luxeon rebel OLEDs and whatever detector I come up with embedded in my ceiling to light up only when you are under them. I've looked into passive infrared, but it's fairly expensive for the components I could find. Any leads for circuits, ideas, or parts? I'd use parts from cheap security lights, but they tend to be around $10 each and I would probably need around12-18 ... kinda painful on the pocketbook. Thanks in advance for any help!

Topic by homba   |  last reply


Potentiometer/Variable resistor with AC advice

I'm a computer store tech who knows how to solder some(but DC stuff only) and who also enjoys cooking, so my ? is: What's the best choice of pot. for use with US household current to actually control the cooking temp of my hotplate? End result is to eliminate the annoying "heat spikes" you get due to lack of a pot. in the design, IE literally everything sold these days turns on at full current/temp until it reaches X temp, basically it's just temporally defined by how far you turn the knob, and your pancakes wind up crispy black around the edges and gooey in the middle  instead of golden brown and amazing all over. I want it to turn on at X current until X temp (like electric frypans/burners did if you're old enough to remember.) All I need to do ( I think) is add a pot/VR into my burner's element  "line" the right way, it already shuts off at X temp just fine. Incidentally, that's the "click" you hear when any home electric cooking device (sold in North America, at least) hits temp or turns on, the temp. control switch thingee connecting. It's NOT a VR/pot, just a pair of electrodes JUST barely touching strapped very tightly to some ceramic discs. It uses thermal expansion of the discs/electrodes to make things just a tiny bit bigger and separate the tiny little electrode spoons  But all that boring geekspeek affects in this configuration as basically just temporal heating, IE no reduction of the amount of heat in my frypan, just the cooking time. Science says if I reduce the amount of electrons flowing thru it just slightly as well,  it'll be colder but still hot and still shut off when it's hot enough. A pot/VR wired in the right way will do exactly that, won't it? After some research I'm thinking something like a 30-50K "B"-taper pot. wired with 2 of 3 traces (https://www.instructables.com/id/Wire-a-Potentiometer-as-a-Variable-Resistor/), I'm looking for a "broad" response range while turning with a tight  "pinch" effect at low end for amazing banana-brown-sugar-pinch-of-nutmeg pancakes with coffee on the tiny balcony/fire escape in the morning but I have no idea how the numbers work for AC currents. Does 120vAC mean a different pot or a diff config/approach altogether? Or should I be looking into AC variable resistors, instead? I know an awful lot about "base" science, enough to get me this far, right, but AC throws me for a loop a lot, and there's a gap in my knowledge/experience, between the basic stuff and how it applies to stuff like my application, I don't get a lot of the numbers/formulas and how to use them.  A VR would the ideal tool here, but they are hard to get in the right form with the electrical qualities I need, whereas pots are usually "turning switches", right?

Topic by MattH68   |  last reply


Send GPS data from smartphon to module GPS connect to arduino

Hello, I want to know, If i can send data GPS from my smartphone to anathor GPS module EM-506 connect to Arduino or raspberry pi. Thank you

Topic by ibrahimenedis   |  last reply


DIY Steering Wheel

Hello, I'm new here. So, lately, I've been thinking about making a steering wheel for my PC, with a simple up-and-down gear box and 2 pedals for acceleration and brake. Steering Wheel. I'm using a polystyrene sheet, to cut out a wheel from it, and in the center, there's space for installing a phone holder. I'm planning to use my phone's gyroscope and simulate it to the PC. Pedals. I've figured by using foams underneath, we can place a nail and a foil separated and when we press the pedal, the foil touches the nail and circuit gets completed. I've a general idea, but I'm stuck on how to give that signal to PC as to simulate as a button (say for acceleration and brakes.) Gearbox. For the gearbox, I figured it might be easier to make an up-down box (as in pulling the level shifts the gear up and vice-versa.) Here too, The part where I'm stuck is giving the signal to the PC. Anyone who can help me, please?

Topic by RohitR78   |  last reply


Fake Pokemon GO Pro

Hello! Right now the best practice to hunt pokemon is to just walk and if the phone vibrates, you look. Thant means you have to hold the phone in hand.  I had an idea for a DIY, but no way to execute it. Idea is simple: -motor vibrator from old phone -Arduino -BT module -battery Turn all above into a braclet for your hand  I owuld need an app or something that, whenever phone vibrates, it would send a command over bluetooth to arduino to vibrate. It would need to check for phone vibrate command as the app doesnt give a notification or annything.  Is the ambition too high ? Is this harder to execute than i tought ? 

Topic by compufreek   |  last reply


Cat chip logger

Could you modify the reader in a chip reading cat flap to log the details of the chips t hat pass through it rather than only let recognized chips open the flap? Chip reading cat flaps exist data logging is possible this I know, how to tie the two together is beyond me. Give me detailed instructions I could do it, but I'm more at home with working out how to wind the detector coil than what to do with it. The reason is this My sister has a problem, she is in danger of becoming a cat lady, or at least over run with strays or other peoples cats. Her current plan other than catching the visitors that are clearly street cats and delivering them to the local shelter, is setting a camera trap aimed at her cat flap and posting the visitor photos on the local area FB page with is this your lost cat under it.  couple of the poor conditioned strays she has managed to get to the shelter have been chipped it is  reasonable to assume that some of the others must be to, and they would be easier to catch possibly if their  owners were trying to do it. Even a simpler system that just connected chipped cat with photo, and there by identified which cats aren't chipped so presumably are true strays not just nominally owned would b of help those could then be targeted for capture and re homing first.

Topic by Stan1y   |  last reply


Mac G3 password hacking?

I got a second-hand mac G3 for Christmas, from the sysadmin at my dad's office. Unfortunately, the sysadmin neglected to remove his accounts (and passwords), so as of yet it's impossible to get past the boot screen. Does anyone have any ideas about how I may crack the password or hack into the account... (changing the root password in single user mode doesn't work...) Oh, and by the way, it's running OS X of some sort, but since we can't log in, it's hard to know what cat it is. Help please!UPDATE:With the help of this site, we made an administrator account. We still don't know the master password, and there are a few untouchable files, but we can basically do whatever we want. The next challenge is to connect it to the internet...If you want to know how we got in, here's what we did:(1) we held down command (the propeller) and S as it booted --> this opened single-user mode, a command-line interface with root priveleges(2) instead of "rm"ing (removing), like the web site suggested, we "mv"ed (moved) /var/db/.AppleSetupDone to /var/db/.AppleSetupDone.old(3) we rebooted, and followed the instructions on the screenWhat did this do? It moved the file that told the computer that the computer was set up, so the computer ran the setup "wizard" like it was the first time the computer had ever been booted. After that, all we had to do was follow the instructions on the screen to set up an administrator (root) account. We also learned that the cat is panther, so we might be updating it to a newer version.Thanks for the help!

Topic by threecheersfornick   |  last reply


Connection to Laser 5mW

Hello, I wanted to ask you guys where should connect +3V and ground from this laser pointer assemly, I have 10 of these lying around. So please tell me where I should connect +ve and -ve

Topic by atwajid123   |  last reply


Xylobands

Anyone  got any theories on how the xylobands work? Especially at the £3 a piece mark? www.youtube.com/watch?v=zxYjRx9fJgY

Topic by kelvinmead   |  last reply


Monitor Temperature And Humidity Via Internet

I would like to build a project which can monitor the temperature and humidity in each one of my rooms in our house and at my daughters apartment.  I would like to use a web page to monitor from anywhere.  I know there are sensors which can do both.  Each room has a computer and is connected to the Internet.  So how do I begin?

Topic by SpaetzleKing   |  last reply


PS3 laptop by Ben Heck

It's always a treat to see what Ben Heck has been up to and his latest device, a PS3 laptop, is no exception. Just plug it in and you'll be up and gaming in no time with its own 17″ 720p HDMI display. As always, the whole thing is custom and if you have a project you'd like him to do he says he can "make the time." See also: Commodore 64 Laptop New PS3 Slim Laptop via TechEBlog

Topic by fungus amungus   |  last reply


555/551 timers 55* Same or Different?

Hello! I'm interested in knowing what timers are the same as the basic 555? Is a 551 the same thing? I am also looking for equavalent Timers that operate in the same way, and have almost identical pinout thanks!

Topic by Sandisk1duo   |  last reply


Shield:FAIL problem in ESP8266-01 with Arduino UNO

I have been working on a Security System project wherein I should get an email if the PIR sensor detects any human presence. I have used an Arduino UNO, ESP8266-01 WiFi module and a PIR sensor. Power supply: Arduino is powered through the USB connection of desktop and ESP8266-01 is powered through the 3.3V pin of Arduino UNO and I have not faced any problem with that 3.3V connection of Arduino. The connection between Arduino UNO and ESP8266-01 are as follows: Arduino UNO ESP8266-01 Rx  Rx Tx  Tx 3.3V  CH_PD & VCC GND  GND   GPIO0 and GPIO2 left open. After successfully uploading the 'BareMinimum' code as found in 'File>Examples>Basics' of Arduino IDE, the ESP8266 is able to communicate correctly i.e. connecting to a wifi network or serving as an access point via SERIAL MONITOR.The ESP8266-01 displays '0018000902-AI03' as the firware version when I type AT+GMR in the serial monitor of Arduino IDE v1.6.8 Then I created an account on https://temboo.com/ and used the 'SendEmail' choreo as found under 'Google>Gmail>SendEmail'. I selected the 'Arduino' option in one tab and 'Arduino Wifi' option in another tab.I then entered the required details including the 'App specific password' and I was able to successfully run the choreo. Problem: I was able to successfully upload the code  to my Arduino UNO that was generated by Temboo. But after uploading the code, when I'm opening my SERIAL MONITOR window from Arduino IDE a message "Shield:FAIL" is being displayed. I'm not able to communicate with the ESP8266 any further. But if I upload the BareMinimum code again, then ESP8266 works normally. I'm a newbie and dont know much about the programming of Arduino though some basics of C are clear.Please if anyone can help me with this, I would be very grateful. The code has been attached.

Topic by JigarF   |  last reply


The Best Suggestion I can Make

The biggest thing that bugs me about the Instructables site occurs to me every. single. time. I visit.  I can't be the only one. This can't be the first time this has been mentioned --- can it? I know how to "fix" it, too, and I have done that on my end.  But still. It seems I ALWAYS have to hit that "View All Steps" button.  EVERY.  SINGLE. TIME. Yeah, I know I can login and change my settings. I did, and I do.  But the login cookie is set too short so it doesn't stick for long.  So I come, back from an email, and AGAIN- I have to go through the first step(s), HIT THAT G*#$&MN; "View All Steps" button, GO  BACK THROUGH THE FIRST STEPS ALL OVER AGAIN AND TRY AND PICK UP WHERE I LEFT OFF.   Arguh. There's this nifty thing called AJAX where you can have more steps loaded when you hit the bottom.  It's a bandwidth saver, but not a complete PITA for the user. All the good sites are doing it. And one is not.  This would be you. Fix this, please.  Your traffic and conversions will increase.  I've hated this issue for long before I became a web designer. Thank you, Instructables!

Topic by awemaker   |  last reply


Arduino genuino 101 iBeacon creation

Hi all, Really quick question: I'm trying to create an iBeacon (or normal beacon) out of the Arduino Genuino 101 board .. it has a built in Bluetooth module but I can't find the code to turn it into a beacon (which I can then use Evothings to create an app to interact with it) - how do I do this / is this possible?  I also have seperate bluetooth modules that I've bought in case I should use that? Ultimately how do I make the Bluetooth module start to transmit the UUID required for the phone to pick up?  If anyone has any code they can show me or anything that would be great - I'm a complete novice! Thanks! Max 

Topic by MaxR46   |  last reply


Multiple Relays controlled by clock Arduino

A friend has a project in mind that involves an arduino controlling multiple relays with the use of a clock. He would like to be able to control each individual relay, and would like to be able to have a different time schedule every day of the week. There would be times where more than one relay is activated, and times when none are. How could this be done?  Could someone direct me in the direction I should be looking? Not sure what to look for here (Most of what i found only works on 24 hour loops)

Topic by RocketPenguin   |  last reply