Relay Schematic

I have a 1 volt signal that I need to latch open a 12 volt circuit for about a minute. Does anyone have a schematic?  

Topic by Divet 7 years ago  |  last reply 7 years ago

CB Radios and Relay Towers

`A buddy and I have portable Citizen Band Radios and we were kinda wondering what cool stuff we could do with it. Also we want to try and build a simple Relay tower to be able to talk to extend the signal. How would we go about doing this?

Topic by Incelism 11 years ago  |  last reply 7 years ago

Multirotor used as a signal relay?

So in my years since first asking a question about electronics on here i have learned a whole lot. So much so that i am working on plans to build my own multirotor, rc car, and control system all from scrap and open source parts. Everything will be arduino controlled for simplicity (i think it will be easier this way) and i would like to use the OrangeRx radio modules.\ So my question is this; if i wanted to put an fpv system on my car and drive it long distances through a neighborhood, how difficult would it be to have a drone follow the car and act as a relay beacon for my transmitter. I know i could easily get the drone to follow the car by using gps but I have no ideas on how to make it a relay, or if thats even economically feasible on a hobby scale.

Question by budhaztm 2 years ago  |  last reply 2 years ago

off relay with delay on timer

Hello smart people! I need to pick your collective brain. The project that I am working on is on my car. I am replacing the front turn signals on my car with an LED strip. The led strip has three wires. One for ground, one for white LEDs, and one for the amber LEDs. If it is just directly connected to the current incandescent bulbs, the white comes on as a running light. When the turn signal comes on, the lights flash white, amber, white, amber..... (not what I want) What I want it to do is turn off the white while the amber flashes, then turn the white back on. I have a delay on relay, but that won't quite work for what I am trying to do. Isn't there a way to just throw a cap and resistor to keep the voltage on a relay to keep the white off till the amber is done flashing?

Question by DanielB93 3 years ago  |  last reply 3 years ago

Will a SSR work with a PWM signal?

Hey guys gotta quick question: I need to be able to cut a PWM signal from a motor for a project. I'm currently using mechanical relays but I'm curious, will a solid state relay work? I know there are easier ways to do this but for right now I'm on a clock and I just want to  know whether a SSR will work for cutting a PWM signal.  Thanks guys!

Topic by HavocRC 2 years ago  |  last reply 2 years ago

Is it possible to build some sort of wifi signal relay station? Answered

I have a linksys Wireless N router which doesnt seem to have the power needed to reach all corners of my house... It also has no antennas (and i don't have money at all so a wifi usb thing isnt an option) so none of the guides here about wifi boosting dont really work. So i had an idea about how to fix this but had no idea how to implement it.... Here's my idea: build some sort of relay station to extend the range R=router @=relay L=Laptop )=signal R) ) ) ) ) ) ) ) ) ) ) ) ) ) @ ) ) ) ) ) ) ) ) ) ) ) ) L Is this possible? I have an old linksys router with two antennas if that helps

Question by quellek2 8 years ago  |  last reply 8 years ago

Cell / mobile phone signal relay.

I work in a building with a metal roof that is also in a small valley. We have absolutely no reception inside the building. Outside we have about 4 to 5 bars, inside there are none. Maybe one if you are near a window. The building is mainly one large open space on the side. I was wondering if it might be possible to passively "pipe in" cell phone reception. I was thinking of a large antenna on the roof that would be connected to a smaller antenna affixed to the middle of the ceiling of the main room. I know the antennas would need to be tuned to the correct bandwidths and I would need a little help with that. (Our carrier is Verizon in the USA btw). Would this sort of setup be feasible?

Topic by Jarun 4 years ago  |  last reply 4 years ago

how to trigger a relay with audio signal (headphone)?

Want output from headphone jack to power relay to turn on power amp

Question by gramparich 4 years ago  |  last reply 4 years ago

I need low power relays.

I've been buying low power relays at RadioShack, but I bought them all. I need more relays and don't want to wait for RadioShack to restock. I need relays similar to this one sold on Digi-Key. The relays have to be low power enough to work directly off of an Arduino.Thanks!

Question by gregr 10 years ago  |  last reply 10 years ago

Hi convert 12v signal to 220v? Answered

Hello! I have a 12v signal and want to convert it to 220v, simply open the passage as a switch (progressive) and I have a 220V source, it would be like a relay but progressive.The signal is not always 12v it could be posible? Thanks! 

Question by labalavermella 7 years ago  |  last reply 7 years ago

Shift Register and Relays? Answered

Using a 74hc595 shift register to a ULN2003 darlington array to control 7 relays, all controlled by an MSP430, connected via RJ11.  The relays are controlling LED Christmas light strings on and off.  Everything seems to be functioning so far but the problem is that relays that aren't being told to turn on sometimes are turning on.  The shift register is connceted with Qa to the master reset of the register so I can clear is quickly, but so far I have been just leaving it high.the other 7 outputs (Qb - Qh) connected to the base pins of the ULN2003 (B1 - B7).  The outputs of the ULN2003 connected to the relay coils, COM connected to 5v, emitter connected to ground.  I have tried pull down resistors on the base pins, I have tried tweaking the code which I tried to set up to just bit bang the shift register, make it as simple as possible just to test it and a sample is provided below for one iteration.  I have it looping through several of these to turn a single channel on each time to check to make sure all the channels work.  It however sometime make a channel just flicker, not turn on at all, or turns several channels on at the same time.  I am curious as to whether this is a hardware problem (pullup/down resistors, filtering caps, more clamping diodes then what is built into the ULN2003, whatever) or whether I am just an incompetent programmer.  I am fairly certain the problem lies somewhere between the driver seat and the steering wheel though.  One thought I had but do not want to try right away is it possible the shift register is bad?  Overheated from soldering?  I try to solder one pin on chips, then a pin on another component, then a pin on the opposite side of the chip, etc to keep chips cool when soldering them, but are the 74hc595 very heat sensitive maybe?  Would appreciate a fast answer, looking to build 5 more of these so I can control all my Christmas lights. This was supposed to be a cheap and dirty project so I didn't get into Triacs and dimming, I just want to turn lights on and off as I see fit.   i = 30000;   P1OUT = 0x00;        //Channel 7 (unused)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x01;        //Channel 6 (Green Wreath)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x00;        //Channel 5 (Red Icicle)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x00;        //Channel 4 (White North)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x00;        //Channel 3 (White South)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x00;        //Channel 2 (Blue North)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x00;        //Channel 1 (Blue South)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT = 0x01;        //Channel 0 (Clear All/Active Low)   P1OUT |= 0x02;       //Clock in   P1OUT &=~ 0x02;   //Clock low   P1OUT |= 0x04;       //Latch outputs   P1OUT &=~ 0x04;   //Latch low   while(i > 0)   {         i--;   }

Question by Electric Spectre1 2 years ago  |  last reply 2 years ago

Wireless Turn Signals

I have toyed around with the idea of making a jacket that has the turn signals and/or brake lights on the back. However, there is a twist, I would like to see a controller box to wirelessly send the signal from a scooter to the jacket. When the turn signals and brakes are used on the scooter it sends a wireless signal to the controller in the jacket which relays that to lights on the back of the jacket. I've seen some jackets with lights wired on to them controlled with an arduino.

Topic by partyone 9 years ago  |  last reply 9 years ago

Why these relay issues?

In my PCB ,AC voltage is passes under the relays(R).. relays too become heat up. Why this happens? Is the issue happens due to AC signal? When I am wired up(each terminal of relays connect to PCB through wire),heating issue solved ( partially )why this happen?

Topic by sforsajith 4 days ago  |  last reply 2 days ago

12v battery low voltage disconnect with relay? Answered

Could i make 12v battery low voltage disconnect with relay and resistor? I was thinking if put resistor in series with relay coil i could lower current so relay would barely work on 12v but when it drops to 10v voltage after resistor would be so small that relay would disconnect

Question by Cekpi7 2 years ago  |  last reply 5 days ago

Using AC to operate a automotive 12 VDC relay

My question is:  can a typical 12 vdc automotive relay be operated (voltage across terminals 85-86)? I am building a car from a riding lawn mower for our grandson.  I want to operate lights from the 12 VDC circuit but I need a signal voltage to actuate the relay across relay terminals 85-86.  I would like to use the existing AC powered light(s) voltage for this purpose?  Possible?

Topic by mndb1971 2 years ago  |  last reply 2 years ago

Help fitting a low voltage indicator into this circuit?

Hello,I know very little about circuits and electrical components, so please be kind.Attached is a picture of a simple circuit. "A" is a 4,5V AAA alkaline pack, "B" is a latching pushbutton switch and "C" is a nicrome wire.In the simplest and cheapest way possible, this circuit needs to alert the user if the battery pack goes below 3V. The indication signal needs to be a "beep", just like a 9V fire detector. (I can't have a LED signal).After some googling, I found that a 3V "low signal relay" could be one option. I prefer to use wires, and not a PCB in my circuit. My questions follow below:1. Is a low signal relay this the cheapest and simplest way, or are there others?2. What components do I need to achive the "beep" and where in the circuit do these components go?3. Will these components draw any power in standby mode, or do they only consume some power when the "beep" goes off? Because if they draw power continuously, I will need to add an extra (coin cell?) battery, as I need to save my alkaline pack for the nichrome wire. The extra battery shoud last for min 3 years.All help highly appreciated.Thanks!/Karolina

Question by karolina81 5 weeks ago  |  last reply 5 weeks ago

Build a 3v Relay Module

Would love a 3v relay module that can be drive by PIRs that output 3v signal.  Thought I finally found what I needed on Ebay, but discovered this is a bogus product that actually needs 5v to be driven. Buyer Beware. Advertised relay PCB as 3v relay. While the relay on the board may trigger independently with only 3 volts, the circuitry of the board demands a higher voltage to trigger the relay. Relay PCB has a EL817 opto-coupler for the input signal, it requires a 5V drive voltage on the Input in order to drive the onboard transistor which controls the relay coil current. With only a 3v drive, there is insufficient current to drive the opto and transistor. The module that the relay is mounted to is falsely advertised as 3.0V because the components on the board need more than 3 volts. In order to drive this relay with a 3v signal device, voltage level shifting needs to take place between 3v device and relay PCB.

Topic by DiyWaterDog 3 years ago  |  last reply 3 years ago

wiring led turn signals to flasher and fuse box?

Led signal lights turned on with regular car flasher relay canister and now with the led flasher relay i get nothing at all!!!!

Question by kyriedanielle 9 years ago  |  last reply 9 years ago

How can I make a TV remote repeatedly send a signal? Answered

Hello everyone. My parents' big CRT tv has a problem with its psu. Its probably the psu's capacitors that have died again. So in order to turn the tv on they have to click the remote's power button again and again and again for at least ten minutes until the tv turns on. It's been repaired 3 times already and because of the repair cost it's not worth repairing it again. Also because it is very big and heavy and it's very hard to move it. Their living room requires a big tv screen but at the moment they cannot afford buying a new tv. This is how I came up with this temporary solution. Make a circuit that will automate the repetitive clicking of the remote's power button, scratch the remote's pcb paint around the power button and solder this circuit. Unfortunately I'm a beginner in electronics and I don't know how to do it. I can only assume that it is possible with the use of a 555 timer and a relay. This is where I need the community's help.

Question by myouknowwho 4 years ago  |  last reply 4 years ago

Looking for 120VAC latching relay that can be controlled by low voltage momentary switch

I'm looking for a device that can switch 120VAC lighting and be controlled by a low voltage momentary switch.  This is just a standard residential lighting setup, so I have only 120VAC to the switch box.  I need this device to supply a low voltage signal to the momentary switch that in turn will control the latching relay for the lighting.  The momentary switches I have are low voltage dry contact closure switches rated to handle 32V AC/DC.  Does something like this exist? Thank you for any thoughts you might have on this..

Topic by olif.divad 1 year ago  |  last reply 1 year ago

Send and receive an electric signal...? Answered

Hi everyone,I just wanted to know how I can send a small electric signal over a distance(not more than 10 meters)wirelessly and receive it at the other end to trigger a relay which in turn of course.. switch higher voltages and do something say...light a LED.I don't know much about frequencies,oscillators and FM/AM or anything.So please let me know how I can get an idea about these and most importantly accomplish what I just mentioned above.

Question by Adarsh_tronix 6 years ago  |  last reply 6 years ago

3 volt signal to trigger 7 volt? Answered

Ok,so I get a 3 volt signal from a detector and use this 3 volt to trigger an alarm which atleast need a decent 7 volts to function.The detector could take a max. of 5 volts input which I got from the 7 volts DC supply.This 5 volts fed,gets transformed into 3 volts after the detection.So let me make this clear,I have a 3 volt and a 7 volt supply.I need to use this 3 volt to trigger the 7 volt circuit.I know what you are thinking-a relay !right?but I couldn't get  a 3 volt relay anywhere(though I got a 5 volt relay).I can tackle this situation in two ways.1)Either by stepping this 3 volt to 5 volts and making the relay do the job.but how? 2)Or some circuit to use this 3 volt to trigger the 7 volts(like a relay but maybe by using ic's).This is the final part of my project and so please help me.

Question by Adarsh_tronix 6 years ago  |  last reply 6 years ago

how to generate signals arduino? Answered

  uhi i want to generate 3 equal variable pulse high with constant pulse low signal that vary with potentiometer and asume it repeat it self every  10us and pulse min is constant 2u and pulse high vary betwwen 5-8u and i want it to carried at specific frequency? i attach the signal i want to generatel 

Question by britich 5 years ago  |  last reply 5 years ago

LED turn signals HELP

I have a 1966 VW Baja bug thats converted to 12v & I want to be able to run 2" round (trailer lights) as my signals. I hooked them up but they dont even light up. I know they work because I pulled them & tested each one. I also know there is power to them & a good ground, as I tested that too. Im just unsure what I need to change next. (the stock signal relay has 4 wires coming off of it & works if I plug in stock type signals) I tryed reading several led post's here & am still lost. Any help would be greatly appriciated.

Question by airdreams1 10 years ago  |  last reply 10 years ago

12v device to switch on a 9v device (signal to switch on only)

I have a device that is switched on by a sensor, powered by 12v, 1.3amp battery. I have another device that is switched on by a mechanical push button switch, this is powered by a 9v battery. I want to piggy back on the wires that switch on the 12v device and take the signal (to turn on only) to the device that is already powered by a 9v battery and normally turned on by a push button switch. ( I want to replace this mechanical push button switch with an "electronic switch" turned on and off the the presence and absence of the 12v signal) I want the 9v device to switch on only when the 12v device switches on and switch off when the 12v device switches off. Also I want the 9v device to only run on the original 9v battery (not accepting power from the 12v device and not returning any power from the 9v device to the 12v device. Is there a switch device/relay that can do this? A device that I can just connect between the wires going from the 12v device to the 9v device? I am a novice to electronics please be kind. I an open to using part from another device, and basic mods. Thank you

Topic by Jvos 7 years ago  |  last reply 7 years ago

Arduino with flow sensor and relay

Hello. I'm needing help on a project with a water flow sensor. Basically, I'm trying to activate a relay (to turn on a motor) when the Arduino board senses any water flow present for 15 seconds or more. I was expecting the relay to turn on after the flow sensor picked up water flow for 15 seconds. After I ran the code, I had water flowing through the flow sensor for 5 seconds and then I shut off the water. The relay still turned on 10 seconds later. I didn't want this to happen. Instead, I would like to have the relay turn on only after there is water flow for at least 15 seconds. Please review my code below. I would appreciate any help. Thank you!!!byte sensorInterrupt = 0; byte statusLed = 13;byte sensorPin = 2;const int threshold = 15000; // thresholdfloat calibrationFactor = 4.5;volatile byte pulseCount; float flowRate;unsigned int flowMilliLitres;unsigned long totalMilliLitres;unsigned long oldTime;unsigned int countstart = 0;unsigned long starttime;unsigned long endtime;unsigned long elapsedtime;void setup(){ Serial.begin(9600); pinMode(statusLed, OUTPUT); digitalWrite(statusLed, HIGH); // We have an active-low LED attached pinMode(sensorPin, INPUT); digitalWrite(sensorPin, HIGH); pinMode(7, OUTPUT);// connected to relay pulseCount = 0; flowRate = 0.0; flowMilliLitres = 0; totalMilliLitres = 0; oldTime = 0; attachInterrupt(sensorInterrupt, pulseCounter, FALLING);}void loop(){ while (1){ if((millis() - oldTime) > 1000) // Only process counters once per second { detachInterrupt(sensorInterrupt); flowRate = ((1000.0 / (millis() - oldTime)) * pulseCount) / calibrationFactor; oldTime = millis(); flowMilliLitres = (flowRate / 60) * 1000; totalMilliLitres += flowMilliLitres; unsigned int frac; Serial.print("Flow rate: "); Serial.print(int(flowRate)); // Print the integer part of the variable Serial.print("L/min"); Serial.print("\t"); // Print tab space Serial.print("Output Liquid Quantity: "); Serial.print(totalMilliLitres); Serial.println("mL"); Serial.print("\t"); // Print tab space Serial.print(totalMilliLitres/1000); Serial.print("L"); pulseCount = 0; attachInterrupt(sensorInterrupt, pulseCounter, FALLING); } if( totalMilliLitres > 0 && countstart == 0) { starttime = millis(); countstart = 1; } if ( totalMilliLitres > 0 ) { endtime = millis(); elapsedtime = endtime - starttime; } if (elapsedtime >= threshold){ digitalWrite(7,HIGH); // Activate relay to turn on motor delay(10000); digitalWrite(7,LOW); // Deactivate relay to turn on motor totalMilliLitres = 0; countstart = 0; elapsedtime = 0; break; } else{ digitalWrite(statusLed, LOW); // Turn the LED off digitalWrite(7, LOW);// turn relay OFF } }}void pulseCounter(){ // Increment the pulse counter pulseCount++;}

Topic by Eric-soberano 1 year ago  |  last reply 1 year ago

Zener Set Voltage Signal Circuit (help)

Hey Everyone- I have been researching on ways to send out an electric signal to trip a relay to shut off my battery charger. I did find some simple circuits and I did the math for what I would need and could not find big enough zener diodes and resistors. Battery+(Resistor)(Zener Diode)(Relay Input)(Battery-) I need this circuit to send a 8.2 or 10Volt 15mA signal to my Relay when the batteries reach 235 volts. Following are the SPECS for the Input signal on my Relay::: Control Voltage Range 3-32 Vdc 90-280 Vrms (60Hz) 18-36 Vrms/Vdc Max. Reverse Voltage -32 Vdc - - - - - - Max. Turn-On Voltage 3.0 Vdc 90 Vrms 18 Vrms/Vdc Min. Turn-Off Voltage 1.0 Vdc 10 Vrms 4.0 Vrms/Vdc Nominal Input Impedance 1500 Ohms 60K Ohms 9.0K Ohms Typical Input Current 3.4mA @ 5 Vdc, 20mA @ 28Vdc 2mA @ 120 Vrms, 4mA @ 240 Vrms 3mA @ 24 V Any help on this would be great Thanks!

Topic by rc_rs_ss 7 years ago  |  last reply 7 years ago

Why wont my 2 channel relay board allow power through the output?

I have a 2 channel relay board connected to an arduino nano and when i send a low signal to it i get the light on the relay board but nothing goes through the common and normally closed pin. I have the relay running on 9v instead of 5v. would this be a problem? when I test it with my multimeter it makes no difference to what is  allowed through. please help  Jamie

Question by Jamie Toeg 2 years ago  |  last reply 2 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. 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

Topic by DiyWaterDog 2 years ago  |  last reply 2 years ago

ring my bell?

I have a switch and when it is opened I want to activate a bell for a second or two. I don’t want the bell to go off again until after the switch has closed and opened again.  What would be a good solution to this?  I’m guessing some kind of relay board but not sure where to look for this.  My bell is 120vac and switch is low voltage DC.

Question by wannab1 6 years ago  |  last reply 6 years ago

Consistent output with arduino

Hi guys! I have a little project that i could use some help with. I am quite new to the arduino, and not that steady in the code, but im hoping on getting there! The project im building is a litte controller that drives a relay output. The controller is connected to a photo-cell that has a two pin output. This output is shorted at various times depending on the movement in front of the photocell. What i need is for the arduino to close the relay for the same period (say 0,5s) each time the photocell circut is closed. And maybe block a repeating signal from the photocell within 0,5s Is this possible in some way? Any help much appreciated!

Topic by maceide 6 years ago  |  last reply 6 years ago

Useless WorldSpace

I have a worldspace satellite reciever lying around at home. I'm from India and WorldSpace service in India has been stopped due to low profit. Now that reciever set and the antenna thing are thrown around useless. I wonder what I can do with it? And is it possible to make a mobile phone signal booster with it??? Or any other idea, anything??? 

Topic by pro2xy 9 years ago  |  last reply 8 years ago

How do I use PIR motion sensor to trigger 3v relay module? Answered

​Looking for help on my project.  See image.  Testing before connecting to high voltage device.  This is my first attempt using a relay. Using a 3v relay triiggered by the PIR signal.  As you see wired now, There is no ground wire coming from PIR only Red + and Yellow signal to relay..  The circuit would not trigger relay with a ground wire to the PIR.  When this does trigger ( without the ground wire on PIR) I noticed on the relay that the LED would not go completely off.  It dimmed showiing that the relay board was still receiving power. So I check to find that when relay turns/switches "off"  the PIR is still sending 2.6-2.8 volts to the relay.  Not enough to trigger the relay, but enough to show power through the LED.  Obviously something wrong here where the PIR or Relay are still drawing power.  Can you help?

Question by DiyWaterDog 3 years ago  |  last reply 3 years ago

Latching relay driver from HT12D

I currently have a remote control circuit and its based on HT12E and HT12D but the problem is that I only have a momentary output from it. I want the circuit to latch but also I do not want to use a latching switch in the transmitter. I already tested some of the latching transistor switch that I found online but I can't make it work using the output signal from the HT12D receiver. Thank you and have a nice day.

Question by Apprentice013 1 year ago  |  last reply 1 year ago

My solid-state relay keeps blinking a lightbulb while in the inactive state, how can I eliminate that?

I have a DC controlling AC solid state relay connected to an arduino diode for control and a light  bulb to the 220 side. While there is no signal coming from the arduino the bulb is blinking insanely fast, when there is arduino signal, the light remains constantly on as intended. How can i make sure there is no load at all on the 220 end while the relay is inactive, so there is no light flickering? Relay specifications: Control: 3/32VDC Output: 48-480VAC 50/60Hz Thanks in advance!

Question by TenshiKiri 7 years ago  |  last reply 7 years ago

12 volt relay help please?

I just purchased a set of electric running boards for my truck. i have to make my own wiring harness. the problem i have is, i need to wire a relay to each running board. i need the relay to power the motor down when the door is opened  and is triggered by the door ajar switch which isnt to hard to do. the hard part is to have the relay reverse polarity so that the motor retracts the running boards when the door is shut and  the signal is lost from the ajar switch

Question by Gearslamer 7 years ago  |  last reply 7 years ago

ARDUINO (Water Pump & 1 Relay module low/high level trigger-12VDC)

I just want to ask, how to turn on the water pump using 12 vdc relay low/high trigger, 9v battery and the arduino uno. I'm just a beginner and also I want to know how will be the wiring of this devices, I'm also having difficulties reading schematic diagrams.

Question by VinceB29 1 year ago

increase cell phone signal coverage.?

On the top floor of my room, i have enough range for my mobile. but on my ground floor, the coverage is very low. my cell phone network is bsnl. is there any way to capture that signal, boost it and transmit the signal inside the entire house??  if we can successfully make a device or a circuit for this then it will be a very usefull work for all.. thanx in advans!! :)

Question by allsparkunleashed 6 years ago  |  last reply 6 years ago

Schematics for a one way RF Relay/Switch?

So my plan is to have a small remote with a single pushbutton that when pressed will close a relay on the reciver, I would like it to have a pretty good range of at least 1000 Meters. I thought of using XBees and Arduinos but i only need the signal one way and only a single channel. Any ideas?

Topic by tomtortoise 7 years ago  |  last reply 7 years ago

Small Temperature Controlled Relay Circuit? Answered

I'd like to build a small temperature controlled relay circuit. I need to sense water temperature and send +12vdc if temp is <95F and -12vdc if >104F. It's driving a linear actuator so it should advance the rod (+12v) at low (<95F) temperature, hold position (0v) between 95 and 104, and retract the rod (-12v) at high temperature. (>104F) Any circuit suggestions? Thanks.

Question by dmcgraw7 10 years ago  |  last reply 10 years ago

WANTED: Bluetooth Bee to Unlock car (or anything for that matter)

I have an Arduino uno, A  relay shield with both 4 onboard relays and an Xbee socket with a Bluetooth Bee plugged in. I need the code to: What I want is to be a able to pair my phone with the Arduino, and after that whenever it detects my phone (or whatever, just a device that has been paired previously) it will do 2 things. 1 is send a low voltage, low amperage momentary ground via relay 1, and 2 send the same via relay 2 to another device (this one would be 12v) Now when it becomes Unpaired it will wait a variable amount of time (Say 20 seconds) and then send another low voltage low amperage ground pulse via relay 3, and repeat the 12V ground pulse via relay 2 again. After that it will repeat the process from the beginning.  Im willing to Pay a Modest fee for this, and afterwards Im going to make an Instructable for anyone wanting to do the same..... and the code will be made freely available for all. Thank you for your consideration.

Topic by wbarfels 7 years ago

Signal amp for vu meter- help!

Hi, I am creating a VU meter with my arduino board soon. I would like the vu meter to output the same amount of light even if the input audio is lower or giher (if i change the volume, I dont want the vu meters range to fluctuate). Does anyone know of a device that will maintain a constant signal voltage regardless of whether the inout signal is high or low? I'm not fussed if this amplifying circuit distorts the signal a bit as I am not actually using it to listen to afterwards. Thanks, Joe

Question by joearkay 7 years ago  |  last reply 7 years ago

Hall effect sensor to trigger relay

Hi! I have a project that needs to sense whether water is flowing through a pipe. I bought a water flow sensor on Amazon ( thinking I could use it as a basic switch, however, it's got a hall effect sensor and I don't understand how to deal with the voltage output. Measuring from the pulse signal to ground, the sensor swaps the polarity each time it's triggered: With water running, I see a positive voltage. Turn the water off and back on, voltage goes negative. My control system can't deal with this. What I need is a simple circuit to turn the sensor's pulse output into a contact closure. Can anyone help? Thank you!

Topic by rpdubz 1 year ago  |  last reply 1 year ago

Reading the max voltage of a low duty cycle PWM?

How do I measure the maximum voltage reached by a very low duty cycle PWM signal without having to alter the signal. The multimeter shows no reading or gives a very brief wrong reading and falls back to zero. I don't have an oscilloscope. Are there any other alternative set-ups to measure just the voltage in this case. Please suggest.

Question by raftor 3 years ago  |  last reply 3 years ago

Arduino code Answered

Hello, I have been trying to make code for my arduino. I would like code to tell my arduino to receive a servo signal from my rc receiver, then detect whether the signal is telling the esc to move forwards or backwards. If the signal is forwards, it simply relays that code to the ESC. If the signal tells the ESC to go backwards, then it sends a signal to go forwards at the speed it would have gone in reverse, while sending out a power source to power a relay. Chowmix12 came up with some code that may help and I put  "//" before all of the code that was not needed for his application to work. Also, this link may be helpful for multitasking.  #include Servo ThrottleServo; //int PWMpin = 2; // connect RC receiver here. //int ServoVal; //int RCinput; void setup() { //Serial.begin(9600); //ThrottleServo.attach(9); // attaches the servo on pin 9 to the servo object //ThrottleServo.write(97); // go to nuetral pinMode(13, OUTPUT); } void loop() { //RCinput = pulseIn(PWMpin, HIGH, 20000); //ServoVal = map(RCinput, 520, 2370, 0, 180); //if(RCinput== 0) { // Signal timed out! digitalWrite(13, HIGH); // ALERT! ThrottleServo.write(97); // Go to neutral throttle position } //else{ // digitalWrite(13, LOW); // everything's fine. // ThrottleServo.write(ServoVal); // Repeat the data to the truck's ESC // Serial.print(" PulseMicros "); // This part is used to debug the values for calibration // Serial.print(RCinput); //Serial.print(" ServoRead "); // Serial.println(ServoVal); // } //} My program so far is as follows. /* created 2005 by David A. Mellis and chowmix12 modified by Justin Baker */ #include const int relay =  10; Servo ThrottleServo; int ServoVal; int RCinput; int PWMpin=2; int relayState = LOW;       long previousMillis = 0;    long interval = 1000;          void setup() {   pinMode(relay, OUTPUT);  Serial.begin(9600); pinMode(9, OUTPUT);  } void loop() { RCinput = pulseIn(PWMpin, HIGH, 20000); ServoVal = map(RCinput, 520, 2370, 0, 180); if(ServoVal>90) { digitalWrite(9, HIGH); ThrottleServo.write(ServoVal); } else{ ServoVal=180-ServoVal; digitalWrite(9, HIGH); ThrottleServo.write(ServoVal); }   unsigned long currentMillis = millis();   if(currentMillis - previousMillis > interval) {        previousMillis = currentMillis;       if (ServoVal >= 90)       relayState = LOW;     else       relayState = HIGH; //this output will turn a mosfet off, turning the relay off       digitalWrite(relay, relayState);   } }

Question by jbaker22 5 years ago  |  last reply 5 years ago

Direction/turn signal indicators making them brighter with led bulb I need help pls

Hi. I somtimes ride a 1985 yamaha ms50 pogal 50cc moped. It has an 6v electrial system where as modern day scooters are 12v. I bought a knew indicater relay for it and checked all the bulbs as the turn signal indicators are not so easy to see flashing. I mean, on average sunny day other road users would need to look hard to see them flashing. the bulbs are 6v 15w and both old and knew flasher relays gives output of 6v 40w. I would feel much safer when turning if I had a bulb that gives a brighter flash to give other road users a better idea when im turning. I can see on the web there is a 6v 5w and 10w bulb I can try or even 6v leds but I dont know much about leds. the stanadard factory fitted indicater buld 6v 15w gives an ok flash at night, but in sunny daylight I would need to be close up to see it flash which is no good! I don't want to change the originality of this little ped since it has been carefully taken care of over the years and has made it in intact into current times as is. I need to come up with somthing that will work and if I replace a buld with a 5w or 10w when it should be 15w I may get a brigher flash or just blow the bulb. I wonder was there a problem or just bad design with the indicator lights on the yamaha ms50 pogal when they first came out in the 1980's as I have seen a couple of them fitted with suzuki fz50 indicators and other makes of bike turn signal indicaters on them. I don't think the flashers are faulty I feel they where just made that way. I could be wrong. I suppose there could be a bad earth on the flashers. Sorry to go on so much about this. Im looking for your suggestions for a brighter indicator flashers which is purely for safety reasons. If car drivers can see where im turning, im less at risk of being nocked off by them. Im thinking a higher or lower wattage incandescent 6v buld or even a replacment 6v led buld ive seen on ebay but as I said. I know nothing about led bulbs or even if they will work on my moped. Would a equivalent 6v 15w led give a brigher flash than a 6v 15w tradisional incandesant bulb? can someone help me here pls Here's the led ive seen on ebay;=item4d08c3be3d these are the standard 6v 15w bulbs i want to replace with brighter led bulbs  

Topic by selectauto 6 years ago

3v Relay Module and PIR sensor circuit troubleshoot

​Looking for help on my project.  See image.  Testing before connecting to high voltage device.  Using a 3v relay triiggered by the PIR signal.  As you see wired now, There is no ground wire coming from PIR.  The circuit would not trigger relay with a ground wire to the PIR.  When this does trigger I noticed on the relay that the LED would not go completely off.  So I check to find that when relay turns "off"  the PIR is still sending 2.8 volts to the relay.  Not enough to trigger the relay, but enough to show power through the LED.  Obviously something wrong here where the PIR or Relay are still drawing power.  Can you help?

Topic by DiyWaterDog 3 years ago  |  last reply 3 years ago

need help with 12 volt relays?

I just purchased a set of running boards off of a 2011 f150. they are electronic and i need to wire them up to a set of relays. what i am trying to do is to make it so that when the door is open it triggers the relay and powers the motors causing the running boards to open up, easy enough. but the problem i am running into is that when the door is closed and the door ajar switch is no longer sending a signal, i need the relay to then reverse the polarity so that the motor will then spin the opposite direction causing the running boards to fold back up. the motors on the running boards do have built in stops so i dont have to worry about leaving power to them. i am also finding out if the door ajar switch on my 2004 chevy silverado uses a positve trigger or a ground trigger. any help i can get would be much appriciated. thanks

Question by Gearslamer 7 years ago  |  last reply 7 years ago

is the output from a solid state relay dependant on the input voltage or current?

Can someone please explain how a SSR works i understand the basics, the led and the photo-diode but im not 100% sure how to use one. im thinking i want to control a large 12v motor that draws a high current (~50A) using the guts of a RC car remote, but i want to maintain the analog signal( if that makes sense...) i dont want it to be on or off, i want to be able to power incrementally. i thought that a SSR would be the right thing for the job.

Question by grimgroper 9 years ago  |  last reply 9 years ago

Controlling a DC motor to only do one rotation and to be triggered using limit switch.

Hi, I'm designing a mini golf hole for a festival in 3 weeks. The idea is to putt the ball in one hole and another ball to be released on another hole. I'm going to use a limit switch to as the trigger signal, but not sure how to get only one rotation on a dc motor and then to reset the trigger. I have to run the whole circuit off 12v battery's. Any and all help would be greatly appreciated. Thanks!

Topic by cmc graphics 6 years ago  |  last reply 6 years ago