inverter

I am making an inverter whivh converts 12 V dc to 230 V ac i am using 2 33 ohm resistor of 1 watt to connect the load on transformer whenever i switch on the ckt the 1 watt resistor are heating to much and multimeter does not show any voltage i am using 12 Volt dc 2.5AH battery as power supply what is the problem

Posted by AbhishekR2 3 years ago


Do you know low carbon living ?

As the subject saying, do you know what is low carbon living ?

Posted by bella2009111 8 years ago


Problem with low battery indicator

Hi guys, I have built a low battery indicator circuit for a 6V battery source. It will light up a led when the voltage reaches below 5V. The 6V battery source powers a servo motor, which is controlled by a microcontroller. The problem I have is that when the servo motor rotates, the led lights up. And when the servo stops rotating, the led goes off. This happens even when the battery is above 5V. Any idea what is wrong? And how I could rectify the problem? I have attached the circuit of the low battery indicator, if it helps.

Posted by kurtselva 5 years ago


help needed

CAN ANYONE HELP ME. IM MAKING A CIRCUIT AND IT REQUIRES THE USE OF A 74LS13 SCHOTTKY, I DON'T HAVE ONE SO ARE THERE ANY ALTERNATES I CAN USE INSTEAD. ALL SURGESTIONS WELCOME

Posted by carl1234 9 years ago


Periscope

I'm looking for a gaget that will allow me too read book titles of prices on low shelves without crawling on all fours. Hey, I'm 74. I look rediculous in libraries and find it hard to get up. Some sort of a periscope might work, or a traveling low chair to scoot along on and handle to help get up.

Posted by Nina Holland 10 years ago


Favorite Low Carb Recipes?

My other half and I have recently come to the conclusion: you can only eat so much talapia. We need help. He's a type one diabetic (the kind you get when you're a kid and some nasty virus destroys your poor pancreas) so that means limited carbs, and preferably the good kind of carbs (fruits, whole grains, etc). I've tried looking up recipes online only to find several very fancy, very expensive low carb dishes. Please help. We are college students who cannot turn to Ramen for this solution! Cheers and many thanks to you, Heather

Posted by mooseinakilt 7 years ago


Running LED on 1.2V rail

I have a board I am working on, and 3 voltages i'm working with: 3.3V, 2.5V, 1.2V. I want to have "Power OK" LEDs for each voltage rail. A look on digikey shows me that 3.3V and 2.5V wont be a problem, but there are no LEDs with a voltage drop less than 1.2V... and if there is, theyre probably expensive. So what is a simple way to have a "Power OK" led for 1.2V rail? p.s. I'm using all 0603/surface mount stuff.

Posted by samurai1200 9 years ago


help with changing transformer output of 8.5VAC 1200mA to 9VDC 1000Ma.

Howdy folk,    The Problem; I need some experienced assistance with changing the output of a transformer from 8.5VAC @1200ma to 9VDC @1000ma. Thanks in advance for any & all assistance.    The Back Story; The left channel went out in my PC speakers, which is designed for 230VAC, I had to destroy the woofer case to get to the transformer, and discovered that it outputs 8.5VAC @1200ma. I have another set of PC speakers (different manufacturer) that takes US voltage (110v) and steps it down to 9VAC @1000ma. I must first plug that transformer into a 100watt 230>110 step down (because I'm currently in the Philippines) and I want to get at least one transformer out of the "equation". I would just buy another system set up for local voltage, but I'm on a fixed income (until I can return to the States) that prohibits this avenue. I CAN afford some small components, but that's about it. Thanks again for any help. -Z-

Posted by Zclip 4 years ago


Ultra low voltage buck converter

I want to step down voltage from a 1.2/1.5v battery to 0.05V. Any advice?

Posted by huzefa 9 years ago


Help! My low voltage, outdoor lighting wont light up - transformer error codes?

I bought a Portfolio 300watt transformer for low voltage outdoor lighting and hooked up a 100' 12 gauge cable (outdoor rated lighting cable) to it. Then I hooked up 4 low voltage lights (12volt 20 watts each). I plugged the transformer in to a gfi outlet that I ran out from the house. And turned it on. The little display flashes "E" and then "1" . The instructions say that the E means that there is a fire hazard so check the circut. So I unhooked every light except one. Same error. I hooked on a different light and unhooked the first one. Same error. Instructions say the cable needs to be under 250'. And the load less than 300w. I am there, except it won't run. Do I have a bad transformer or is there something that I am missing? Oh, and this is to light my haunt in my front yard, so I am running out of time! Thanks for any advice! Matt

Posted by mckeephoto 8 years ago


LOW COST BATTERY for CELL phone

My old LG flip phone still has lots o' pics, contact info, etc. I don't wanna throw it out, but the battery no longer holds a charge. I'd like to recycle the old battery, but when plugged into a charger with no batt, the phone  will not turn on.   Why can't I power it up on the wal-wart transformer alone?  Do I really need to spend $40 on a battery just to access old pics n stuff? Is there some proprietary circuit in there that "says" to the phone "I'm here"  other than just plain old voltage? Although the old battery seems to work just well enough to access data as long as it's plugged in, I'd like to get rid of said battery in case it eventually leaks.

Posted by Toga_Dan 4 years ago


wind turbine speed?

i have herd that the minimum amount of wind required to power a (homemade) wind turbine is 10 m.p.h. is that true? and whats the maximum wind speed?

Posted by Sun Gear 7 years ago


Wanted: 9 volt light sensor module

Calling all you that know and enjoy making circuits. Here is my problem.  This is too bulky of a solution with a relay switch and 12v battery pack. https://www.instructables.com/id/DC-Low-Voltage-LIght-Sensor-Switch/ What I would like is a 9 volt input and 9 volt output.  Actually, whatever the input should equal output.  So if I connect 3 v battery, I want 3 v output.  Right now I need 9 volt in = 9 volt out.  No Relays!!!  Simple and clean circuit board only. The LED can't be soldered to the board.  I need the capability of extending from the board with wire to adapt to my needed projects. On another note, if you know of something already on the market, please send a link.  I will be happy to make the purchase. OH... no modules that need a microcontroller.  Need a stand alone module. Thanks! Looking forward to hearing back soon. The Water Dog

Posted by DiyWaterDog 1 year ago


PVC pipe at low temperatures

I have a question for spudgunners and other people who know about PVC. I've heard that PVC becomes bitter at low temperatures, so you shouldn't expose your spudgun to low temperature, but is it okay to leave it out in the cold and then warm it back up for use later? Does that affect the strength of the PVC? I have a problem storing some PVC in an heated environment during the winter.

Posted by starwing123 9 years ago


Low voltage health problems

Hello, I saw a great project on youtube, a water button, and gave it a try. it works, all it does is when one touches water, a led turns on, just a proof of concept. But what I was worried about, is if there are any negative health impacts of 3.3 v going though you and into the ground? The power is not noticeable, but still, I worry. ps. I did Google this, but couldn't find anything.

Posted by penguins 9 years ago


shelf couch

I have a fairly barren room with two windows on one wall, and I would like to make a low bookshelf underneath the windows that will also be wide enough for a pseudo-couch to lie down on for reading and other relaxing activities. I took more time making the paint drawing below than this post, so APPRECIATE! Thanks 8D

Posted by Schisler7 9 years ago


Questions about computer stereos

Hi! I'm building a portable amplifier from old computer-speakers and I have a couple of questions about them. 1. How do I make the stereo-speakers mono the best way? 2. Is it possible to make low- and high-pass filters to a simple amplifier as the computer ones? I thought I'd connect one bigger speaker (a whopping 5" one!) to amplify the low frequencies and one small to amplify the high frequencies. This would work the best with a 1-channel amp. Thank you in advance, hope you understand what I'm looking for! P.S. Please move the thread if it is in the wrong category, wasn't sure if it suited better under "music" or "tech".

Posted by Henell 10 years ago


low voltage photoelectric switch for led spotlight

I need help. I am making an led spotlight to mount on the flagpole and light up the flag at night. I have the lights from a 46 led flashlight. I've attached 2- 3.7v Li rechargeable batteries and a solar cell charger. Everything works great, except I want a photoelectric switch to turn light on and off. Right now, it is on a manual switch mounted to the pole. I cannot find and don't know how to build a 3.7v photocell circuit. I've tried 12v (all I can find except for 120v) and they won't work. I need to know what I need to make a 3.7v circuit/switch, and how to tie it in to the existing system. Can anyone help me? Thanks for any input. I am a novice, so be gentle. BJ

Posted by cottnpickr 10 years ago


Windows XP Running with as little as 18MB or RAM

I managed to run Windows XP (stable) with as little as 18MB of RAM, Originally for my PSP to run.With Dosbox i can Allocate up to 16 MB of RAM, with a little tweaking i could get it to reach 18MB.But XP Can't run in DOSbox, But it Can Run in Bochs, It may be slow but hey, If i can Run Windows XP on my psp, It is still an accomplishment.Here are some screenshots of it Running is QEMU, On a PCSo what do you think, I am planning to port QEMU to the PSP so we can finally make this a reality, BOCHS only works in 1.50 Firmware, and i don't see a psp Slim with 1.50 and my PSP is a Slim and ...well you know.Well ThanksBe sure to comment(and rate, Just because it is neat seeing topics with a rating...) And tell me what you think!~ReCreateEdit: Now i uploaded a video!(or i am uploading a video...i have to remake it due to the stupid 10MB limit)

Posted by ReCreate 9 years ago


Simple, efficient, low-cost, solar energy equipment

I am looking for a DIY simple, low-cost solar water heater and solar light that will work in any kind of weather and still be able to supply atleast some working heat and light. Please suggest.

Posted by rseni 9 years ago


Would a glass, vacuum-insulated thermos be able to withstand the extreme cold of liquid-air?

I am in the middle of designing a system to produce liquid air using the von linde process. the termos would not be under any pressure, but it will get quite cold. can a thermos using a glass vacuum insulated inside be able to withstand temperatures below -180 degrees celsius?

Posted by pedrogabman 8 years ago


Can a glass, vacuum insulated container withstand temperatures in the -180 degree celsius range?

Is it possible to store liquid nitrogen and oxygen in a vacuum insulated container for a short period of time? i have a thermos that i though might work, but i want to be sure that im not going to have the thermos explode in my face when i try it. this is an old beefy thermos that can take at least 190 degrees celsius, but im not sure about the other direction.  

Posted by pedrogabman 8 years ago


Recent is using low number of years again.

Recent is using low number of years again in Answers... Again

Posted by iceng 2 years ago


Low Voltage Higher Current?

I am having a strange problem on a USB peripheral.... it is a digital radiography sensor that overheats. I believe it may be due to the power supply to the motherboard, but I don't know for sure. I am ASKING FOR YOUR HELP in reasoning out what may be the cause. Anyone with computer/electronics experience, PLEASE HELP!!! I was told that my power supply is too low voltage, and that current is going up in the USB peripheral causing it to heat up. I always thought V=IR means that if voltage drops so does current. But in other places I read that if voltage drops, current goes up so that the wattage/power usage stays the same according to P=VI. So which is it? V=IR or P=VI ? If my power supply has too low voltage, will the current in the device increase to compensate? Or will it just have a lower current? Does it depend on the circuit and the exact electronics in the USB peripheral? Here is my SETUP. It is SIMPLE: Antec AR-350 power supply connected to a motherboard Asus P5N7A-VM in an ATX case. All I have otherwise is a SATA hard drive and a SATA DVD-ROM in there. That's it! Problem started to happen about 1.5 years after I got the computer. That is why I am thinking maybe it is the power supply, or maybe it is the motherboard?  The computer works fine in every other way! It uses Windows XP and has a wireless keyboard/mouse which also works fine. BIOS settings screen Hardware Monitor shows voltage for USB 5v reading about 4.9v, within tolerance. However, one of my USB peripherals is a digital xray sensor. It works ok a few times, then it starts to overheat and fail. This only happens on this computer. When I use another computer (like a laptop) with the same USB hardware it functions ok and never overheats. I don't have any problems on the other computer, even thought I am using the same software/drivers. I bought a different ATX case with a new power supply, and just moved the motherboard, HD and DVD over. Now the motherboard BIOS shows under Hardware Monitor that it is getting 5.2 V instead of 5v, so it is higher! Also the 12 V is higher (around 12.2v) and same for the 3.3V. All the voltages are HIGHER! So I have yet to test this new configuration with the USB peripheral sensor.  Could the motherboard be faulty? I did notice the motherboard looks "curved" with the area under the CPU sort of bulging out. However, with this motherboard you will see there is a huge heat-sink/fan that gets clamped over the CPU and that may be bending the board. Keep in mind the board works perfectly otherwise, so I am wondering WHY it would only affect USB for this one peripheral and not for the keyboard and mouse? Maybe the circuitry on the keyboard/mouse is more tolerant to low voltage? Would appreciate your thoughts please.

Posted by edy 6 years ago


Arduino starts up automatically

Hello instructables, i ran the code below in the arduino uno, (4 motors, 2 L293D driver chips) void loop() {   digitalWrite(motor_pin1,LOW);    //forward back   digitalWrite(motor_pin2,HIGH);   digitalWrite(motor_pin3,HIGH);      digitalWrite(motor_pin4,LOW);   digitalWrite(motor_pin5,LOW);    //forward front   digitalWrite(motor_pin6,HIGH);   digitalWrite(motor_pin7,HIGH);      digitalWrite(motor_pin8,LOW);   delay (5000);     digitalWrite(motor_pin1,HIGH);   //turn right    digitalWrite(motor_pin2,LOW);   digitalWrite(motor_pin3,HIGH);     digitalWrite(motor_pin4,LOW);   digitalWrite(motor_pin5,HIGH);   //turn right    digitalWrite(motor_pin6,LOW);   digitalWrite(motor_pin7,HIGH);     digitalWrite(motor_pin8,LOW);   delay (2000);     digitalWrite(motor_pin1,LOW);    //stop moving   digitalWrite(motor_pin2,LOW);   digitalWrite(motor_pin3,LOW);      digitalWrite(motor_pin4,LOW);   digitalWrite(motor_pin5,LOW);    //stop moving   digitalWrite(motor_pin6,LOW);   digitalWrite(motor_pin7,LOW);      digitalWrite(motor_pin8,LOW);     while (1); } by right, the motors should stop infinitely due to the while(1), but this is what happens instead : initial                 : loop1 12 secs later   : loop 2 1 sec later        : loop 3 1 sec later        : loop 4 .... why is it running more than once?

Posted by fujiapple 6 years ago


new to arduino, want to run a dual display for 2 sensors

I'm new to the Arduino community.  wanting to set up a dual radar setup with 2 ultrasonic sensors,  (Ultrasonic Sensor Module HC-SR04), and outputting to a pair of 7 segment displays ( two 7 segment displays each).  I've found a code to do a single could use a lot of help to output two at the same time, basically 2 lanes without 2 units.  im using an arduino mega, ordered a unor3 and hopefully it can be made to run on one or the other. code is as follows: /* HC-SR04 Sensor    The circuit:     * VCC connection of the sensor attached to +5V     * GND connection of the sensor attached to ground     * TRIG connection of the sensor attached to digital pin 2     * ECHO connection of the sensor attached to digital pin 4  */    /*  This is a radar ping sensor that calcultates the speed of an  object traveling away or towards the sensor. I took some of this  code for the HC-SR04 Sensor implementation by Tautvidas Sipavicius. The rest  is original code from me. I know that the seven segment display  code is not the best to look at or the most optimized but it  serves its purpose just fine and is easy to understand.    Written by Matthew Ladd  */   const int trigPin = 2; const int echoPin = 4;   void setup() {   // initialize serial communication:   Serial.begin(9600);   //First 7 segment (ones place)   pinMode(30,OUTPUT);//F   pinMode(31,OUTPUT);//G   pinMode(32,OUTPUT);//E   pinMode(33,OUTPUT);//D   pinMode(34,OUTPUT);//C   pinMode(35,OUTPUT);//B   pinMode(36,OUTPUT);//A   //Second 7 segment (tens place)   pinMode(37,OUTPUT);//F   pinMode(38,OUTPUT);//G   pinMode(39,OUTPUT);//E   pinMode(40,OUTPUT);//D   pinMode(41,OUTPUT);//C   pinMode(42,OUTPUT);//B   pinMode(43,OUTPUT);//A } void zerofirst(){   digitalWrite(30,LOW);   digitalWrite(31,HIGH);   digitalWrite(32,LOW);   digitalWrite(33,LOW);   digitalWrite(34,LOW);   digitalWrite(35,LOW);   digitalWrite(36,LOW); } void onefirst(){   digitalWrite(30,HIGH);   digitalWrite(31,HIGH);   digitalWrite(32,HIGH);   digitalWrite(33,HIGH);   digitalWrite(34,LOW);   digitalWrite(35,LOW);   digitalWrite(36,HIGH); } void twofirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,HIGH);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void threefirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void fourfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,HIGH);//A } void fivefirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,HIGH);//B   digitalWrite(36,LOW);//A } void sixfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,HIGH);//B   digitalWrite(36,LOW);//A } void sevenfirst(){   digitalWrite(30,HIGH);//F   digitalWrite(31,HIGH);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void eightfirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,LOW);//E   digitalWrite(33,LOW);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void ninefirst(){   digitalWrite(30,LOW);//F   digitalWrite(31,LOW);//G   digitalWrite(32,HIGH);//E   digitalWrite(33,HIGH);//D   digitalWrite(34,LOW);//C   digitalWrite(35,LOW);//B   digitalWrite(36,LOW);//A } void zerosecond(){   digitalWrite(37,LOW);   digitalWrite(38,HIGH);   digitalWrite(39,LOW);   digitalWrite(40,LOW);   digitalWrite(41,LOW);   digitalWrite(42,LOW);   digitalWrite(43,LOW); } void onesecond(){   digitalWrite(37,HIGH);   digitalWrite(38,HIGH);   digitalWrite(39,HIGH);   digitalWrite(40,HIGH);   digitalWrite(41,LOW);   digitalWrite(42,LOW);   digitalWrite(43,HIGH); } void twosecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,HIGH);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void threesecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void foursecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,HIGH);//A } void fivesecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,HIGH);//B   digitalWrite(43,LOW);//A } void sixsecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,HIGH);//B   digitalWrite(43,LOW);//A } void sevensecond(){   digitalWrite(37,HIGH);//F   digitalWrite(38,HIGH);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void eightsecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,LOW);//E   digitalWrite(40,LOW);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } void ninesecond(){   digitalWrite(37,LOW);//F   digitalWrite(38,LOW);//G   digitalWrite(39,HIGH);//E   digitalWrite(40,HIGH);//D   digitalWrite(41,LOW);//C   digitalWrite(42,LOW);//B   digitalWrite(43,LOW);//A } long distanceOverTime(long first,long second){  return ((first-second)/.1)*.0223693629;//taking cm/s to mph } long holder;//store the cm from last time through loop. long temp;//used to store the speed value after changes int counter; void loop() {   // establish variables for duration of the ping,   // and the distance result in inches and centimeters:   long duration, inches, cm;   int tens;   int ones;   long Speed;   // The sensor is triggered by a HIGH pulse of 10 or more microseconds.   // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:   pinMode(trigPin, OUTPUT);   digitalWrite(trigPin, LOW);   delayMicroseconds(2);   digitalWrite(trigPin, HIGH);   delayMicroseconds(10);   digitalWrite(trigPin, LOW);     // Read the signal from the sensor: a HIGH pulse whose   // duration is the time (in microseconds) from the sending   // of the ping to the reception of its echo off of an object.   pinMode(echoPin, INPUT);   duration = pulseIn(echoPin, HIGH);     // convert the time into a distance   inches = microsecondsToInches(duration);   cm = microsecondsToCentimeters(duration);   Speed=distanceOverTime(holder,cm);   holder=cm;//after speed caclulation so take the cm value for another calculation   Speed=abs(Speed);   if(Speed!=0 || counter==10){     temp=Speed;     counter=0;   }else{     counter++;   }   if(temp>=100){    zerofirst();    zerosecond();   }else{     ones=temp%10;     tens=temp/10;   }   if(ones == 0){     zerofirst();   }else if(ones==1){     onefirst();   }else if(ones==2){     twofirst();   }else if(ones==3){     threefirst();   }else if(ones==4){     fourfirst();   }else if(ones==5){     fivefirst();   }else if(ones==6){     sixfirst();   }else if(ones==7){     sevenfirst();   }else if(ones==8){     eightfirst();   }else if(ones==9){     ninefirst();   }   if(tens == 0){     zerosecond();   }else if(tens==1){     onesecond();   }else if(tens==2){     twosecond();   }else if(tens==3){     threesecond();   }else if(tens==4){     foursecond();   }else if(tens==5){     fivesecond();   }else if(tens==6){     sixsecond();   }else if(tens==7){     sevensecond();   }else if(tens==8){     eightsecond();   }else if(tens==9){     ninesecond();   }       Serial.print(inches);   Serial.print(" in, ");   Serial.print(cm);   Serial.print(" cm, ");   Serial.print(Speed);   Serial.print(" mph");   Serial.println();     delay(100); }   long microsecondsToInches(long microseconds) {   // According to Parallax's datasheet for the PING))), there are   // 73.746 microseconds per inch (i.e. sound travels at 1130 feet per   // second).  This gives the distance travelled by the ping, outbound   // and return, so we divide by 2 to get the distance of the obstacle.   // See: http://www.parallax.com/dl/docs/prod/acc/28015-PING-v1.3.pdf   return microseconds / 74 / 2; }   long microsecondsToCentimeters(long microseconds) {   // The speed of sound is 340 m/s or 29 microseconds per centimeter.   // The ping travels out and back, so to find the distance of the   // object we take half of the distance travelled.   return microseconds / 29 / 2; } again, all your help and thought are appricated

Posted by herb1977 9 months ago


Low pass filter on LED Music Controller

I've purchased following controller: http://www.ebay.co.uk/itm/131775427312 I was wondering whether it was possible to create a lowpass filter with potmeter, so that the LED only will be changing to the low frequencies?

Posted by FrederikH5 2 years ago


Stepper Motor Library

Hi! Sorry, I was unable to put library below. So simple and yet so not so simple. How do I get the library in the folder so the program compiles/? Thanks 56Frank library for 28BYJ48 Stepper motor and ULN2003 driver. Here is the source code for our 28BYJ48 stepper motor, ULN2003 driver library, as well as an implementation. Check out the diagram for the wiring. The header file: __________________________________________________________________ #ifndef Stepper_h #define Stepper_h class StepperMotor { public:     StepperMotor(int In1, int In2, int In3, int In4);    // Constructor that will set the inputs     void setStepDuration(int duration);    // Function used to set the step duration in ms     void step(int noOfSteps);    //    for(int sequenceNum = 0;  sequenceNum <= noOfSteps/8; sequenceNum++){         for(int position = 0; ( position < 8 ) && ( position < ( noOfSteps - sequenceNum*8 )); position++){             delay(duration);             for(int inputCount = 0; inputCount < 4; inputCount++){                 digitalWrite(this->inputPins[inputCount], sequence[(int)(3.5 - (3.5*factor) + (factor*position))][inputCount]);             } Arduino         }     } } _______________________________________________________________________ An implementation: _______________________________________________________________________ #include StepperMotor motor(8,9,10,11); void setup(){   Serial.begin(9600);   motor.setStepDuration(1); } void loop(){   motor.step(1000);   delay(2000);   motor.step(-1000);   delay(2000); } Step a certain number of steps. + for one way and - for the other     int duration;    // Step duration in ms     int inputPins[4];    // The input pin numbers }; #endif ___________________________________________________________________ The cpp file: ___________________________________________________________________ #include #include StepperMotor::StepperMotor(int In1, int In2, int In3, int In4){     // Record pin numbers in the inputPins array     this->inputPins[0] = In1;     this->inputPins[1] = In2;     this->inputPins[2] = In3;     this->inputPins[3] = In4;     // Iterate through the inputPins array, setting each one to output mode     for(int inputCount = 0; inputCount < 4; inputCount++){         pinMode(this->inputPins[inputCount], OUTPUT);     }     duration = 50; } void StepperMotor::setStepDuration(int duration){     this->duration = duration; } void StepperMotor::step(int noOfSteps){     /*         The following 2D array represents the sequence that must be         used to acheive rotation. The rows correspond to each step, and         the columns correspond to each input. L     */     bool sequence[][4] = {{LOW, LOW, LOW, HIGH },                           {LOW, LOW, HIGH, HIGH},                           {LOW, LOW, HIGH, LOW },                           {LOW, HIGH, HIGH, LOW},                           {LOW, HIGH, LOW, LOW },                           {HIGH, HIGH, LOW, LOW},                           {HIGH, LOW, LOW, LOW },                           {HIGH, LOW, LOW, HIGH}};                           int factor = abs(noOfSteps) / noOfSteps;    // If noOfSteps is +, factor = 1. If noOfSteps is -, factor = -1     noOfSteps = abs(noOfSteps);    // If noOfSteps was in fact negative, make positive for future operations     /*         The following algorithm runs through the sequence the specified number         of times     */

Posted by 56Frank 11 months ago


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Posted by Mud Stuffin 6 years ago


help with my sketch anyone please....

const int TxPin = 6;       //lcd pin const int buttonPin1 = 2;  //pins that are for const int buttonPin2 = 3;  //buttons to open valves const int buttonPin3  =  4;                       // and pumps const int buttonPin4 = 5;    const int pumpPin = 9;        //pin that turns on the pump    const int valvePin1 = 13;        //pins that run valves const int valvePin2 = 12;       const int valvePin3 = 11; const int valvePin4 = 10; int buttonState1 = LOW;           //setting the button state to low int buttonState2 = LOW; int buttonState3 = LOW; int buttonState4 = LOW; const int PROBE1=A0, PROBE2=A1, PROBE3=A2, PROBE4=A3; int MOISTURE_LEVEL = 250;                              //the value after the valves and pump goes ON #include SoftwareSerial mySerial = SoftwareSerial(255, TxPin); void setup() {        pinMode(pumpPin,OUTPUT);    // sets pumpPin to output    pinMode(valvePin1,OUTPUT);    // sets valvePins to output    pinMode(valvePin2,OUTPUT);    pinMode(valvePin3,OUTPUT);    pinMode(valvePin4,OUTPUT);    pinMode(TxPin, OUTPUT);          //lcd pin to output    digitalWrite(TxPin, HIGH);            digitalWrite(pumpPin, LOW);         digitalWrite  (valvePin1,LOW);    digitalWrite(valvePin2,LOW);    digitalWrite(valvePin3,LOW);    digitalWrite(valvePin4,LOW);    mySerial.begin(9600);    mySerial.write(22);                // turns display on    mySerial.write(17);                // turn on lcd back light      mySerial.write(12);                 // Clear  LCD    delay(5);                          //required delay after clear Lcd                                    } void loop(){    mySerial.write(128);        // sets sets lcd cursor to line 0 space 0   mySerial.print("S1-");      mySerial.write(148);           // sets lcd cursor to line 1 space 0   mySerial.print( "S2-");      mySerial.write(168);              //sets lcd cursor to line 2 space 0   mySerial.print("S3-");      mySerial.write(188);              //sets lcd cursor to line3 space 0   mySerial.print( "S4-");      mySerial.write(132);               //sets lcd cursor to line 0 space 4   mySerial.print (analogRead(A0));    mySerial.write(152);               //sets lcd cursor to line 1 space 4   mySerial.print (analogRead(A1));    mySerial.write(172);                //sets lcd cursor to line 2 space 4   mySerial.print (analogRead(A2));     mySerial.write(192);               //sets lcd cursor to line 3 space 4   mySerial.print (analogRead(A3));                if (analogRead(A3) < MOISTURE_LEVEL) {     digitalWrite(pumpPin, HIGH);     digitalWrite(valvePin1, HIGH); }    else   {     digitalWrite(pumpPin, LOW);     digitalWrite(valvePin4, LOW); }   if (analogRead(A1) < MOISTURE_LEVEL)   {     digitalWrite(pumpPin, HIGH);     digitalWrite(valvePin2, HIGH); }   else   {     digitalWrite(pumpPin, LOW);     digitalWrite(valvePin2, LOW); }       if (analogRead(A2) < MOISTURE_LEVEL)   {     digitalWrite(pumpPin, HIGH);     digitalWrite(valvePin3, HIGH); }   else   {     digitalWrite(pumpPin, LOW);     digitalWrite(valvePin3, LOW); }    if (analogRead(A0) < MOISTURE_LEVEL)   {     digitalWrite(pumpPin,HIGH );     digitalWrite(valvePin1, HIGH); }   else {     digitalWrite(pumpPin, LOW);     digitalWrite(valvePin1, LOW); }

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LOW COST HIGH VOLTAGE ELECTRONICS AVAILABLE FOR $3 US SHORT TIME

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