J Reynoldson
esp32intdelayonly.zipUpdated delay program with small code fixes and tabbed source, better commentsx-zip-compressed - 3.18 kB - 09/13/2021 at 06:36 |
|
|
esp32intdelayvox.zipUpdated delay with VOX code. General tidy up and automatic calculation of optimum memory use and sample rate. Also set up with tabs for readability and more comments. Some small non-fatal bug fixes.application/x-zip-compressed - 10.23 kB - 09/10/2021 at 05:54 |
|
|
VOXtiming1.JPGBasic timing diagram for time shifting VOXJPEG Image - 41.23 kB - 12/18/2018 at 02:33 |
|
|
esp32svox.JPGRevised hookup for ESP32S with VOX adjustment potJPEG Image - 46.81 kB - 12/16/2018 at 02:04 |
|
|
repeater_test.mp4Test of the repeater. Note you can see the signal strength meter on the receiver on the left show the incoming transmission. The transmitter on the right shows it transmitting the start beep almost immediately (which we are hearing through a separate CB receiver off camera) and then we hear the delayed transmitted audio about a second later. If you look closely, you can see the LED on the ESP32 light up as well.MPEG-4 Video - 3.17 MB - 12/13/2018 at 21:34 |
|
|
buffer_filter.jpgBuffer and low pass filter for use on both input (anti-aliasing) and output (step smoothing) of the ESP32 based delay. Assumes a minimum 20000/sec sampling rate.JPEG Image - 106.76 kB - 12/10/2018 at 04:23 |
|
|
2khzinputraw.jpg2kHz sine wave line level input (+/- 1.5V) before filtering and delay. This is the maximum input the ADC will take without clipping.JPEG Image - 269.43 kB - 12/10/2018 at 02:43 |
|
|
DACunfilteredoutput.jpg2kHz sine wave output from the ESP32. Sampling rate was 32000,/second, the input was filtered with a 9.6kHz low pass filter.JPEG Image - 123.19 kB - 12/10/2018 at 02:43 |
|
|
delayedandfiltered.JPGFinal 2kHz sine wave output after post filtering with a 9.6kHz low pass filter. Note that the original input line level has been preserved. It looks good!JPEG Image - 24.89 kB - 12/10/2018 at 02:43 |
|
|
esp32echo.inoA program to insert an echo into realtime audio. Customisable delay and intensity.ino - 2.38 kB - 12/04/2018 at 02:25 |
|
|
Sample_Results_audio.amrAudio sample. You are hearing the original voice audio, then the result after going through the repeater system. Recorded using a phone sound recorder! Quite intelligible, under the circumstances!amr - 10.38 kB - 12/04/2018 at 02:00 |
|
|
Audio delay and VOX using ESP32
This simple project implements an audio delay and time-shifing VOX using the ESP32S ADC and DAC capabilities.