BC457 instead of TIP31? Answered

For the circuit in the pic can I use BC547 instead of TIP31

Question by adarshnarsaria   |  last reply

can anyone suggest an alternative for TIP31? Answered

Hi!I want to use a TIP31 in my infra red detector circuit and cant find it any shop,could anyone suggest any other transisitor which fulfills the same purpose?

Question by Adarsh_tronix   |  last reply

Trouble blinking leds with TIP31 Answered

Hello everybody, I am trying to make a blinking circuit to hook up to the LED strips in my car so they blink in sync with the bass.  I have made a circuit following some instructable here, I can't recall which it was. Anyway, I'm pretty sure the schematic is correct, because the leds blink. Now two problems arise: I have hooked them up to the subwoofer out of my radio ( a Kenwood kdc something), and after enabling it I was told to put a speaker coil in series to increase the resistance, in order not to fry the channel. Is this right? Next, the leds don't quite blink, but they pretty much stay on all the time, with very little variation, I suppose because the sub out gives out quite a high voltage, so the transistor does not open the enough for the leds to blink properly. I was thinking of putting a resistor/potentiometer in series with the signal coming from the radio, in order to reduce the voltage and have a better blinking effect. What do you think? Thanks in advance, peace :)

Question by en_rov   |  last reply

Are the TIP31 and TIP31B or C interchangable?

I  want to make a version of https://www.instructables.com/id/LED-Music-Sync-Headphones/ but I have found three types of the TIB31.  A B and C.  Are they interchangable?

Topic by finfan7   |  last reply

TIP31cg transistor

HI all, im trying to make this project, a led box that flashes to music https://www.instructables.com/id/Music-LED-Light-Box/ i purchased a tip31 transistor, but when i got home i discovered it was a top31cg. is this going to be a problem? thanks all!

Topic by i-like-cheese 

My DC adapter has AC output is that right?

Hey guys i obviously need more sleep. I brought a wall adapter so i could make a huge amount of LED flash to music. Now that i have it home I released i have a different one than i intended to pick up. Its 12VDC 2.5A i only wanted the 1A mostly cos it was cheaper. Will the extra 1.5A make a huge difference especially to the TIP31? The adapter actually has AC Adapter written on it and the packaging says Switchmode Regulated Plugback. I'm gonna need a multimeter before i plug the LED's to the power or will it be safe to just go by the numbers on the adapter? Thanks

Question by Scotty3000   |  last reply


So as you can see in the video at the end of both songs I am having a issue with it cutting/shorting out. All i can think of is the tip31 transistors im using are overheating maybe? but what is really wierd is it shorts back to the speakers?? I have one transistor driving the blue leds and one driving the red leds. the red leds are being powered by a 9v supply and the blue is 15v( dont remember the MA but they both provide plenty. They are wall warts. When i  plug in the 9v power supply it makes a high pitch buzzing noise.... If anyone has any pinters i would appreciate it. Thinking of adding more transistors.... I cant figure out how to link it so just copy paste the link below into your browser... https://www.facebook.com/video/video.php?v=4627718865303&saved; and i'm following this diagram cause it does not have a switch like the others. https://www.instructables.com/id/Flashing-Leds-to-Music-multipurpose/

Question by ARGMISTER   |  last reply

where do i wire the speaker into the circuit?

So i built this Music LED Light Box from Motadacruz's Instructable, but it doesn't have any audio, so i wired an audio jack in (as shown by the little yellow boxes in the diagram) but when i plug headphones or speakers in, the audio works, but the lights don't. can someone please tell me where to wire the audio jack in at?

Question by xxInSAniACxx   |  last reply

Which diagram would work best(want leds to work at their max potential, Help? Answered

Specs on all 3 leds  1 watt, red green blue Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA (if you pick a diagram with a resistor please let me know what rating Ty)

Question by dougiedougworld   |  last reply

I need a diagram, please from a knowledgeable person, can any one make me a diagram for leds to sync to music please? Answered

I need a diagram. i have parts and will pick up more if needed, please specify what voltages, ohms, needed as well if heat sinks are needed,  Parts i have. One of each of the following leds. surface mount LED is mounted on a 0.80" diameter aluminum disk which serves as a heatsink and provides solder spots to simplify connection. Cree X Lamp 7090,  1 WATT GREEN ULTRA-ULTRA BRIGHT LED 45/ 73 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA Cree XLamp 7090,  1 WATT BLUE ULTRA-ULTRA BRIGHT LED 19/ 31 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA Cree XLamp(TM) 7090, 1 WATT RED ULTRA-ULTRA BRIGHT LED 34/ 55 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA I have 3  Tip31 NPN TRANSISTOR, 3A 80V TO-220 I have One 12' CABLE, 3.5 MM STEREO PLUGS BOTH ENDS i have one  Stereo plug splitter ( so i can listen to music while lights are going) I have 100' of red and 100' of black 24Ga hook up wire i also have, solder, solder gun, wire snips/strippers, access to resistors and power supplies, volt meter/ohm meter, and other tools I would like it to be a wall plug system using an adapter The leds were about $10 per so please give me real diagrams, dont waste my time or money. I will be double checking the diagram, and checking to make sure all math is correct, will i need resistors and what type, will i need heat sinks even tho the leds already have 1 built in, ?

Question by dougiedougworld   |  last reply

I have 3 led's, would the diagram work the way i want,?

 i would like the 3 leds to work as follows, left speaker left led, right speaker right led, and central led will be off of both speakers, i am quite sorry for my ignorance, i am very new to this and it is a gift for a friend, so i really want to know as much as i can before  i start blowing things up :),  each led is 1 watt and works best at 700 ma from what i understand, but can work between 350-700, so i am hoping 600 ma is fine, i have a wall plug adapter with switch for 3-12v, i will be using a v meter to test these numbers are accurate, it says current 600 ma., in my previous posts i was recommended to buy a CCR, but i haven't the  time to order this,  will this power source eliminate the need? i also have picked up quality heat sinks, and arctic silver, i am not the best at electronics, i do have a relative who works with HVolt  batterys and knows some about electronics, he works at TDI in nj, hes busy so cant ask him much, i am hoping this to be my last post, please help a guy out, thank you all for your support and positive and helpful comments first image without resistors second with

Question by dougiedougworld   |  last reply

What could be wrong with my led light box? Answered

Hey you guys I did everything correctly but its still not working. Here's a pic of mine. I know its not the leds because they light up when I plug them up to a 12v source.Also thats a brand new tip31 and im using 8 Triple A batteries?

Question by tramont   |  last reply

How to add a op amp to this circuit?

I built this circuit a while ago but the only problem i have with it is that i have to use electronics like my iPod, laptop, or anything with a high volume output. So I started reading about op amps and hwo they "jack up the signal" and I stated wondering could I somehow integrate it into my circuit so that my audio input is higher therefore allowing me to use my cellphone, tablet, and e.t.c? Currently I have a LM324 Quad amp i know fr sure i wont need all those pin. I also have a tip31 and 2N3904 transistors.

Question by tramont   |  last reply

Is there a way to make el wire response on music with a tip31?

Hello guys Is there a way to make el wire response on music with a tip31? I  have to make el wire response on music this is for a project for school can someone give me flow chart/blue print of how to make this?   Many thanks  P.S Sorry for my bad English I am from the Neterlands

Question by bobkokke   |  last reply

Led problem

Hello, I apologize for my bad English, I'm from a country where English is not the official. I have a problem, I made ​​a circuit to synchronize the lights to music with a TIP31. the problem is when I connect it to the amplifier is blown, I fixed it, but I do not understand why it burns, can you help me? Is it because TIP31 is powered by 12V? If you could help me find a solution?

Topic by mitza sb   |  last reply

Music LED Sync?

For the circuit in the pic can I use the transitor listed here  instead of TIP31, SMD LED Strip instead of the 4 LEDs, and can I power it with an ATX Power Supply as it also has 12v DC output???? Thanks in Advance.....

Question by adarshnarsaria   |  last reply

Can i put an LM386 amp into the circuit with my TiP31 for flashing LEDs? Answered

Hi guys i have a problem. I went to the local electronic store and got everything for my op-amp except for the stereo jack and socket. Do i need those or can i just plug the wires somewhere in the existing circuit? What i just got bits for and haven't made up yet.. https://www.instructables.com/id/LM386-Audio-Amplifier/ What i have made already but lacks oomph... https://www.instructables.com/id/Sync-LED-to-Music/ Thank You

Question by Scotty3000   |  last reply

Tip 31 LEDS blink to music

You know how you can make an led blink to music with a tip31 , i was wondering, but didnt have enough spare cash (what can a 14 year old do) could you make an led display target shaped as in concentric circles of leds then apply resistors of increasing resistance from the inside out so that the light would "flare out" from the center as it gets louder and softer?

Question by Algag   |  last reply

LED that lights on music

Hello there guys, I want to make an LED that lights on music. I know how to do it, I've seen some other instructables and i've understood how it works. My question here to you guys, instead of the TIP31 transistor, can i use something else because i don't have a 12V power supply, i only have a 5V one. Can you guys provide me with an answer, a tip, schematic or anything else that could help me? Thx alot, John.

Question by Shetsans   |  last reply

Can an led brake light pulled from a spoiler be used inside my car and beat to the bass in my music?

So i pulled out an led brake light from an old nissan spoiler that has its own circuit and resistors on the board with only + and - wires coming out. Is there any way that i could hook it up to the headphone output that i have in my current car? I know that i have to use a tip31 transistor but i dont know how to wire it up. 

Question by gman15   |  last reply

HELP: Blinking light circuit ( Music Synced)

Hi I'm trying to build a music synced blinking light circuit. However I AM A NOOB. I don't know almost anything about electronics and stuff. But i'll manage. So the first problem is that I cannot get tip31 or any tip transistors in the market. All I have is BC547 NPN transistor or 2N2222, General Purpose NPN Signal Transistors ( TO92 ). And I wish to attach blue led strip in the circuit. and will be powering the circuit using 12v power adapter. Please suggest how much of Amps should it be of. A diagram of it would also help :) Thanks in advance!

Question by vmahajan3   |  last reply

How am I able to use a potentiometer to cycle through a color wheel for a RGB LED, as well as make it react to music?

I have just started experimenting with circuits and what not, but i need some help, because I'm new, clueless, and trying to learn. My goal is to create a circuit that will allow me to use a single potentiometer to change the color of a RGB LED, as well as allowing an input for music to have it pulse to the beat. For the potentiometer, would that require an Arduino? Searching on Google has not yielded many results but they all tend to use an Arduino, and for the reaction for music, would I be able to use something along the lines of a tip31, like how it was used in another instructable (https://www.instructables.com/id/Music-LED-Light-Box/). Any help or insight would be great. Thanks for your time.

Question by Cynda2 

Problems with USB Port on Homemade speaker box, why can't I listen to music and charge at the same time?

Okay, so I have a speaker box that I made myself with a kitted 7w audio amp. I put that in a box with a decent 4 inch speaker, and that was working great. Then I decided that I really need to add some sound reactive lights, so I got a TIP31 transistor and hooked that up along with a 7805 5v regulator to a USB port so I can charge my devices with it. So, the USB port works great, and so does the speakers and lights. But *not* when I plug in my device to charge while it playing music through the 3.5mm audio jack. It gives off this weird fuzzy sound, but still charges. On my multi meter it shows continuity between the USB port and the audio input and speaker, so I first thought that maybe I didn't have something grounded quite right, but it all appears to be set up right. Is there some sort of filter I can set up so that I can charge one device and play music at the same time on the same device? Or would need to set up the two circuits on different power sources? I would really rather not do that for the simple fact of trying to keep it simple... Here's my schematic of it (sorry about it being sloppy, I did it rather quickly but everything on there should be right). Here's a better quality picture of the schematic

Question by froggyman   |  last reply

How do i make these leds dance to music? Answered

I want to hook the three led's i have up to my PC sound jack, i have parts, i may need more, but my question is how do i hook them up? please leave comments and or diagrams thank you What I have (for now) 3 Leds: 1 WATT ULTRA BRIGHT LED GREEN 45/ 73 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA 1 WATT ULTRA BRIGHT LED BLUE 19/ 31 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA 1 WATT ULTRA BRIGHT LED RED 34/ 55 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA   TIP31 80V TO-220 Transistor (is this the correct one?) i have 3 i also have 24g hook up wire, 3.5 splitter, 3.5 cable with plugs, many battery options as well as wall adapters OK do i have what i need, do i need resistors, what ohm rating, and watt rating, what volt source?  i dont need it to be portable, will be on desk, a wall power supply would be best, please try to make me a diagram with parts i have, but if more are needed i have plenty of resistors to choose from Ty. and a store right down road :) https://www.instructables.com/answers/I-need-a-diagram-please-from-a-knowledgeable-pers/

Question by dougiedougworld   |  last reply

Basic circuitry help? [not yet resolved]

(I wasn't sure if this should be a comment on the Instructable or not, as it is a bit long, and I have some pictures..) I am following a sound-reactive LE 1.D tutorial and having a bit of trouble. The circuit consists of a SPDT switch, resistor, LED, transistor, and a 3.5mm stereo jack. When I play music using this stereo jack, I get no response from the LED. I'm trying to make something on a breadboard for the first time, so I'm thinking maybe I'm missing something because of that. Here's how the machine is supposed to work: - Positive charge flows to SPDT switch, and if it's in the correct state, continues to the 150 ohm resistor - Anode of LED is connected to the resistor, and the cathode is connected to the "emitter" lead of a TIP31 transistor ("base" is wired to the power bus) - The "collector" lead of the transistor is attached to one of the outputs on the stereo jack - The ground wire on the stereo jack returns to the common lead of the SPDT switch. Perhaps I wired something wrong? I've included pictures if the description is not sufficient. EDIT: I've modified the circuit a bit - maybe I can take pictures / draw a diagram tomorrow. Now, here's how it works: - Positive charge flows from positive side of the power bus to the "base" lead of the transistor - Collector lead of the transistor is connected to the left-channel lead of the stereo jack (also, the ground pin of the stereo jack is connected to the negative side of the power bus) - Emitter lead of the transistor is connected to a 150-ohm resistor - Resistor is connected in series with two LEDs - The cathode lead of the second LED returns to the negative lead of the power bus The LEDs do turn on now, but that's the problem - they are always at full brightness no matter the volume of the music. Even if no music is playing, the LEDs are fully lit. I've used a multimeter to check what's happening, and after pressing the negative lead of the multimeter to the cathode lead, and the positive lead to the anode lead, it shows a constant voltage of 1.986 V. I don't understand how this isn't working - I've verified that the collector lead is correctly connected to the left-channel wire... maybe I should try the right channel? Or a different cable? tl;dr: Rewired and the LEDs are always at full brightness. Transistor doesn't seem to be affecting the emitter output, for some reason..

Topic by hansengel   |  last reply

Odd problem with EL Wire... Help?

I’ve been working on this circuit and I can’t quite get it to work right. I wrote out all of my diagnosis in detail, so it’s a bit of a text wall, but perhaps you can just look at the drawings and skim the “odd part” and know what I’m doing wrong. Thanks so much to anybody who can help me out with this. Description: It uses a remote controlled LED controller to turn some EL Wire either on, off, or flashing to music. There is also an override button, to use in case the LED controller stops working. The LED controller requires 12v and outputs the same voltage. I put the diodes in to protect the controller from the 12v that would come across the override button if it was on and the controller output was off. The transistor is a TIP31. The wires going to the override button and to the EL wire are both detachable (using a molex connector). Diagnosis: The override button turns the wire on just fine, but the LED controller does not. When I did a quick test before assembling things by attaching only the controller to the power source and the wire to only the controller, it worked just fine. Additionally, when the override/EL molex is disconnected, I am able to get a +12v reading from my multimeter coming out of the LED controller. When it is connected, however, I am not. The LED controller outputs no voltage, and when I switch the output on, there is often but not always a small blip of voltage. Here’s the odd part: If I turn the controller output on while the override button is on, it DOES output 12v. I can then turn the override button off, and the wire remains lit, the controller continues to output 12v. As soon as I turn the controller off, it will refuse to turn on properly again until the override button is activated (even though I detect 12v going into it). I tried replacing the diode on output 1 with a transistor (generic npn, a BC337 if I remember correctly), and adding an LED between the output and ground. Neither fixed the problem, but I think that I will keep them because the transistor does not have a 1v drop like the diode does, and the LED is an easy way for me to tell whether or not the controller is outputting. One thing I did notice is that the LED did light dimly when the override button was on yet the controller was off.

Topic by theqwertman