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  1. B

    Help building a voice-recording circuit with Nuvoton ISD1730

    Hi all! Thanks for creating this amazing online community. I'm currently working on building the "Example #1" circuit listed on page 19 of 26 in the datasheet for the Nuvoton ISD1730PY chip (image attached). I've attempted to translate the schematic into a breadboarded circuit, which I've...
  2. C

    Midi controller / DAC interface not recognised (Device descriptor request failed).

    I have an EKS XP10 midi controller with a Burr Brown DAC. When plugging in the controller it isn't being recognised by Windows. I have two more of the same controllers. Only this one has this problem. I have checked and confirm there is steady 5v across legs 1 and 4 of USB socket on the...
  3. C

    Audio bridge between two phones

    Hello everyone. My scenario is the following: I have two phones let's name them P1 and P2. I need to get the sound from P1 Out and redirect it in P2 In (Mic). I also need to do the same thing but reversed, to get the sound from P2 Out and redirect it in P1 In (Mic). So basically when P1 will...
  4. P

    LTSPICE opamp circuit sim

    I'm trying to sim the input circuit of an audio EQ, but I'm getting only DC at the output. This is what I'm trying to simulate: It's the input section of this schematic: Here's what I've created, the .ASC is attached: I'm using an LT1057 model as it is described as a drop-in...
  5. T

    does anyone else think this could be a million dollar idea?

    I have some bluetooth earbuds and I want to make it usable with an aux cord like bluetooth headphones. I could just directly connect a 3.5mm port but then the current would also travel into all of the other parts. Would that be a problem? If so couldn't I just use diodes to prevent this?
  6. N

    Circuit bricks Nano (power supply)

    Hi, I am making a module for a DIY modular synthesizer. The module applies an ADSR-envelope to an audio signal using a 10K MPC41010 digital potentiometer. I suspect, I made an error in the circuit, since I now have 2 Nano's which will not power on from USB (pwr led flashes a few times and then...
  7. J

    Sampling ultrasonic signals

    Hi, I want to sample 4 audio sources which frequencies would be between 30 kHz and 40kHz (ultrasonic signals). Is there a microcontroller with ADC that could do that?
  8. sr13579

    What is the pinouts for this module?

    I specially need those 4 pins togather on one aide of this module.
  9. sr13579

    JDY-62 Datasheet required!

    Hello Friends! Can you help me with the pinouts of this bluetooth audio receiver module?
  10. sr13579

    How to add Next and Previous Button with Android's headset/earphones?

    I tried to figure out how to add different functionality with headset controller. So far I found how to make signals for volume up and down and play/pause. Now I want to add two switch which can do the next and previous operations. How am I supposed to do that?
  11. ElectroMaster

    FM Transmitter (#1)

    This circuit is a simple two transistor (2N2222) FM transmitter. No license is required for this transmitter according to FCC regulations regarding wireless microphones. If powered by a 9 volt battery and used with an antenna no longer than 12 inches, the transmitter will be within the FCC...
  12. sr13579

    What is the name of this IC used in bluetooth audio receiver and FM radio?

    I bought tgis cheap bluetooth receiver that has a chip #AC1805E88767 or something like that with symbol of PI(3.1416) on it? I tried to search about this IC but nothing comes up. I tried to take a photo but the chip is very small. Does any of you know about this chip?
  13. M

    One speaker is picking up radio module noise

    I currently made a module to my project which isn't quite functioning correctly. It's 4 distinct parts on one board. The radio I/O, the two independent sound amplifiers out of the LM386's and the RFID card reader. This is the circuit: The actual inverter IC I used is 74HCT04 because it...
  14. Holes Flow

    Reduce Audio Sampling Bandwidth for FHT/FFT

    Experts, I am looking for a way to use the standard arduino FFT (no FHT for non-AVR) but only for a small section of the audio spectrum. Instead of breaking down the entire spectrum, resulting in wide bins even after /2, I'd like to only sample 2 or 3kHz of the spectrum, and thereby have a more...
  15. blueboy

    Phase Shift problem in audio equilizer

    Hello everyone, I am new to filter design and I want to design an audio equalizer. I used Sallen key topology design calculator from: http://www.changpuak.ch/electronics/Sallen_Key_Bandpass_light.php I designed five band bandpass filter having simple low pass and high pass for initial and final...
  16. J

    Remove HDMI Audio?

    I wish to remove the audio properties of my HDMI display cables. Is there a way to do this by making an adapter that cuts out certain pins? The problem: I'm having problems with Audio being diverted to my monitors instead of the desired audio device. (Windows 10 has a tendency to re-route...
  17. sr13579

    How to use a TDA7052 IC properly?

    After a massive crash on LM386 I moved on to TDA7052. This is a very good IC so far. I want to make sound boxes and sell them. That is why I want to know more info than datasheet if available. I have some questions though: 1. How to secure the connection to reduce noise? 2. How to protect the IC...
  18. sr13579

    Is it safe to use a 5V-1A USB(Samsung mobile) charger for lm386?

    Hello everyone, A brother from my hometown told me to make a mini amplifier that can pull the power out from a USB charger(or PC USB). I happened to working on a logic gate IC and burned the IC while using a USB(power bank) charger. I want to know is it safe to use a 5V-1A charger to power the...
  19. E

    Is true-RMS meter required for audio signals?

    I know what true-rms is, but I wonder if it is required to measure a real audio signal. With "real" I mean a mix of many frequencies, not just a test pure sine wave. I suppose an average meter should work fine, but I've got no true-rms to compare. Would an average and true-rms meters differ...
  20. A

    volume/output power control using a knob in TAS5424C-Q1

    Hi Folks, It seems that the gain in the IC TAS5424C-Q1 can be controlled using I2C protocol. But I'd like to keep it simple using a hardware (rotatory knob). Is it possible to control the volume and output power using hardware control such as a rotatory knob generally used in car head units...
  21. E

    Class D amplifier for arduino

    I was playing about with transistor amplifiers nd I built this class D amplifier intended for use with the arduino ( or any other microcontroller) https://siliconjunction.wordpress.com/2017/02/28/class-d-amplifier-for-the-arduino/ Thanks Matt!
  22. J

    Z-2300 Generic Logitech Control Pod Help

    Please consider reviewing my Interpretation of this generic control pod diagram, to help me out in understanding the workings of this circuits. http://blog.jseaber.com/wp-content/uploads/2010/04/remoteV100.pdf I'm new to these electronic circuits, and this might be my first time trying to...
  23. vivid

    LED Audio Spectrum Analyzer Circuit

    Here is a Music Spectrum using NeoPixel RGB LED Matrix and ARM microcontroller. I used the online circuit design tool EasyEDA.com to draw the circuit. This link is my competed circuit diagram and PCB, where you can see it very clearly.
  24. CBB9

    Audio Triggered Switch Help

    I'm hoping someone here can help lead me in the right direction on an experiment of mine. In my car I have an automatic starter that includes a wire that when given the 12v negative connection will trigger the automatic starter. What I would like to do have this negative connection activated...
  25. A

    An audio amplifier for beginners

    Hey guys I just uploaded my tutorial on how to build a simple audio amplifier using an LM386 chip. When using the maximum supply voltage it can reach a power output of roughly 1 watt. Hope you find it useful. Schematic <Mod edit: If you have something to share, please post it here. Do not...

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