Internet radio and audio file player on ESP32-S3

Theoretically as you write practically not necessarily.

I have the grounds connected on the PCB and without the display the radio on the board plays perfectly zero hum noise interference.

When I connect the OLED there is noise and crackling, the inverter is to blame.

When I supply power to the display from another source, e.g. a second 5v charger, there is silence.

I am thinking of using this to power the display.

https://allegro.pl/oferta/przetwornica-separu...-dc-b0505s-1wr3-vout-5v-200ma-hlk-17476660801

If it works as two power supplies it will be beautiful.

I've already ordered one and we'll see how it arrives.

Greetings....

>>21880034 Theories about correct ground routing I "buy" and agree with 100%. I don't buy the theory about the UTP cable because there is no differential signal from which to eliminate the "common" interference

@ryba_82 Don't you have OLED flickering after adding the beads ? In my case, this operation caused the inverter to run at the end of its strength.
Generally the source of the problems is the inverter (non-original) to boost the voltage for the display. Replacing it with an original from Microchip and changing the supply from 3.3 to 5V solves a lot of the problems. The Chinese replacement (what's on the PCB) can't handle a 5V power supply (I slaughtered one). The PCB layout is for these displays drawn "at the knee". The power supply to the inverter is drawn all the way through the PCB and at the end there is not even one capacitor at the inverter input. There is a second version of the PCB for these displays and the layout there is much better done.

FMT signal is a design mistake. It was supposed to be XSMT (soft mute) so that the DAC could be muted via GPIO. Fortunately there is a series resistor that we don't mount so no ground loop will happen there. The SCK has a short enough connection that there won't be any drop and noise generation there either.

SPI itself does not generate such fast signals and 10OHm resistors are sufficient. The easiest way to check this is to unplug the 14V inverter from the OLED and apply an external 12V-20V supply to this pin. There will be complete silence.

robgold wrote:

Power supply to the inverter pulled all the way through the PCB and at the end there is not even one capacitor at the inverter input.

And have you tried adding such a capacitor directly on the inverter legs ?

Greetings ...

>>21881513 Yes, I have a 22uF/10V MLCC doped in ( could be 10uF just left over from a Dell laptop repair).
I have replaced the inverter with a TPS61040DBVR and supply it with 5V instead of 3V. For the large OLED (the 5.5 one) I bumped its voltage up to 15V and it works stably. I will probably still bump it up to 16V.



And here is a picture of the display PCB from Ali, where the layout is much better designed and the inverter is powered from 5V. Microscope photo:


Here the appearance of the whole PCB:


@kula350 you made something like a "shield" out of UTP cable - question why when there are dedicated shielded audio cables? Good, inexpensive and looks nice.

kula350 wrote:

the twist creates capacitance along its length and overall, at each point, drains the high pulses to ground.

And where in the twisted pair do you get the ground? Unfortunately you are mistaken, it works on a completely different principle.

kula350 wrote:

Because if something is radiating, I don't put on ferrites that need to be tuned just

Sorry, WHAT? What kind of tuning? Nothing is tuned (unless a fool), ferrites are made of materials suitable for the frequency. A core from a noise filter in an RF amplifier will behave completely differently.

kula350 wrote:

Ground routing is one way of dissipating that interference which passes right through them.

This is the key! A wrongly routed ground can spoil a good project.

>>21881136 it flickers a little, but this effect is not visible somehow very intensely (blue OLED). Surprisingly, it flickers more in the quieter copies, I have now done such an experiment. By the way, terribly "unique" are these displays. I have 3 units, 1 bought last year, 2 units this year, from a different supplier. Layout the same, but level of interference different. As for the SPI, that was one of my suspicions, I'm basing it here on my professional experience, but actually I haven't observed it in mine. As for the external OLED power supply, some time ago in an act of desperation I wanted to make an external 14V linear power supply to mute the damn thing.
As for the FMT, I, in my first assembly on a contact board, connected it to ground, by wire, without a resistor. It buzzed very nicely, so I preferred to warn others....
Chinese replacements for chips from reputable manufacturers are often of inferior quality, e.g. I had this problem on an ESP32-S3 board with an LM1117, theoretically 800mA, and the ESP32 would reset when connecting to WiFi. I suspected the power supply, however on it the 5V was like a wire, without any squat. But for the 3.3V line - here it was fun, as the stabiliser was shutting down at around 360mA. Replacement with an original Texas and the problem disappeared.

Czech colleagues.
I would like to ask you about the project "Kula350..Cmentarne". Where can you establish a calendar, that would show Slovak men?

And switching off the radio... OFF, when I switch off or encoder or remote control button on the
oFF "a svjeczi vyswjetlaczi na cervono Displaj svjeczi.
How do I switch it on again with the remote control? -nevjem.
I switch it on only by pressing the encoder button.

Thank you for your help

>>21882917 All these displays have a very differently set inverter voltage level. On top of that, I have the impression that this "made in china" TPS "replacement" is very unstable. Especially as they supply it with 3.3V and it is supposed to generate 14.7V from this voltage. Often it fails to do so and because of this it is set to 12V. Everything flashes gently. Swapping to the TPS from the TI and boosting Uwe to 5V solves this. As I wrote this "swap" such a voltage boost doesn't serve because it doesn't seem to have the intended 5V supply voltage. I've also noticed that this higher voltage is most common for the white versions. The green and yellow versions of OLD have it lower. I guess it's a way to make it "durable".

As for the SPI, also from professional experience I preferred to throw in series resistors on the lines. They are not essential but don't get in the way and after testing I found that this SPI is basically not audible.

As you can see from your experience they are already counterfeiting even stabilisers ...hands are falling off.

>>21883606 Here it may not so much be that the LDO was fake (it had no TI markings), but that it was of poor quality.

We used to do research in my company wanting to introduce Chinese manufacturers of simple semiconductors. The Chinese can be divided into two groups: reliable companies which are OEMs for e.g. NXP and also sell under their own brand, these have high quality, repeatable parameters, etc., and inferior companies, saving on testing (e.g. my LDO could have been so untested), but also saving on e.g. silicon.

We had such a case of a stabiliser, or a DC-DC converter, I don't remember exactly. After knocking down the case, we compared the silicon. The Chinese one had half the surface area.... Well no miracles, you can't cheat physics, higher energy density -> faster ageing and degradation. To be clear, the catalogue parameters practically the same.

There is also a third category, sellers of production waste, which is dealt with by unauthorised dealers, the so-called brokers. You supposedly buy the original, it looks like the original, but it does not hold the parameters. You write to the manufacturer with a complaint, he asks for the label and a photo of the circuit. And you get a reply that the label is a fake or does not match the markings on the circuit (date-code). You have most likely bought a discard from production.

Sorry for the off-topic

I have a question for the subject guru whether this Kenwood remote control malenism can be replaced by this

https://pl.aliexpress.com/item/1005002882998279.html?

>>21886120 Any remote control will work, the condition is that it must be an infrared remote control working in the NEC coding as this is the only one implemented. Ask your dealer if this is an IR remote control in the NEC standard. If it is, you can learn it in the Evo on the website under settings/remote config.

I have a question for the subject guru whether this Kenwood remote control malenism can be replaced by this

https://pl.aliexpress.com/item/1005002882998279.html?

@amrowek unfortunately you will not use this remote control in the EVO project.

Hi, is the interface available in English? Thank you.

>>21886865 In Evo is in English.

Hello as a lot of questions about PCBs have come in on priv to me, I am attaching all the PCB versions I have prepared with short descriptions of the versions.
The summer season is starting so other work takes precedence, so I am making available what I have.

And yes, briefly the most important information and PCB versions below.

Here we go

Version Rev.1.0
- PCB version without SMD components
- Jumpers are made on the top layer of the PCB as tracks, so you don't need to assemble them in case of factory PCBs
- Prepared for ESP32S3 Uno (PCB put on sandwich)
- No encoder output
- No audio amplifier
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 7-pin connector for OLED display
- Connector 3-pin - audio output for external amplifier
- Connector 2-pin - derived 5V power supply for external amplifier
- Robgold's software upload
- Dimensions - board size the same as the ESP32S3 UNO board - or Arduino UNO)





Version Rev.2.0
- PCB version without SMD components
- The jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted in case of factory PCBs
- PCB version with one encoder
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 16-pin connector for OLED display
- Audio amplifier PAM8403
- Power supply USB printer socket
- Robgold col's software upload
- Dimensions 99.95mm x 88.54mm





Version Rev.2.1
- Everything as in Rev.2.0
- Added voltage dividers for the audio signal to reduce the audio level at the input of the PAM8403 power amplifier





Version Rev.2.2
- Everything as in Rev.2.0
- Added potentiometers for the audio signal to adjust the audio level at the input of the PAM8403 power amplifier





Version Rev.2.3
- Everything as in Rev.2.0
- Power amplifier has been changed, PAM8403 has been removed and PAM8406 amplifier module has been used





Version Rev.3.0
- PCB version without SMD components
- Jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted in case of factory PCBs
- PCB version with two encoders
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 16-pin connector for OLED display
- Audio amplifier PAM8403
- Power supply USB printer socket
- Robgold col's software upload
- Dimensions 99.95mm x 88.54mm





Version Rev.3.1
- Everything as in Rev.3.0
- Added voltage dividers for audio signal to reduce audio input level power amplifier PAM8403





Version Rev.3.2
- Everything as in Rev.3.0
- Added potentiometers for the audio signal to adjust the audio level at the input of the PAM8403 power amplifier





Version Rev.3.3
- Everything as in Rev.3.0
- Power amplifier has been changed, PAM8403 has been removed and PAM8406 amplifier module has been used





Version Rev.4.0
- PCB version without SMD components
- The jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted on the factory PCBs
- PCB version without encoders
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- Connector 8-pin for LCD display
- 4-pin connector for SD card reader on display
- Note: Do not use two card readers at the same time !!!
- Audio amplifier PAM8403
- Power supply USB printer socket
- MAJSTER XXL software preload
- Dimensions 98.04mm x 87.25mm





Version Rev.5.0
- PCB version without SMD components
- Jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted in case of factory PCBs
- PCB version with two encoders
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 16-pin connector for OLED display
- Audio amplifier PAM8403
- Power supply USB printer socket
- Version contains two ESP32 modules the second one for BT transmission
- Uploaded soft by kol Ejcon (mod of original soft by kol Robgold)
- Dimensions 135.26mm x 88.27mm





Version Rev.6.0
- PCB version without SMD components
- The jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted in case of factory PCBs
- PCB version with one encoder
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 16-pin connector for OLED display
- Audio amplifier PAM8403
- Power supply USB printer socket
- Connector 2-pin for POWER LED
- Connector 2-pin for POWER button
- Connector 3-pin for ADC keyboard connection
- Robgold software upload
- Dimensions 108.84mm x 88.54mm





Version Rev.6.1
- Everything as in Rev.6.0
- Added voltage dividers for the audio signal to reduce the audio level at the input of the PAM8403 power amplifier





Version Rev.6.2
- Everything as in Rev.6.0
- Added potentiometers for the audio signal to adjust the audio level at the input of the PAM8403 power amplifier





Version Rev.6.3
- Everything as in Rev.6.0
- Power amplifier has been replaced PAM8403 has been removed and PAM8406 amplifier module has been used





Version Rev.7.0
- PCB version without SMD components
- Jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted in case of factory PCBs
- PCB version with two encoders
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- 16-pin connector for OLED display
- Audio amplifier PAM8403
- Power supply USB printer socket
- Connector 2-pin for POWER LED
- Connector 2-pin for POWER button
- Connector 3-pin for ADC keyboard connection
- Robgold software upload
- Dimensions 108.84mm x 88.54mm





Version Rev.7.1
- Everything as in Rev.7.0
- Added voltage dividers for the audio signal to reduce the audio level at the input of the PAM8403 power amplifier





Version Rev.7.2
- Everything as in Rev.7.0
- Added potentiometers for the audio signal to adjust the audio level at the input of the PAM8403 power amplifier





Version Rev.7.3
- Everything as in Rev.7.0
- Power amplifier has been changed, PAM8403 has been removed and PAM8406 amplifier module has been used





That would be the gerber files in the bulk archive attached.
Personally at my place I have the PCB versions Rev.1.0, Rev.2.0, Rev.3.0, Rev.4.0 running






The other versions were created for the needs of electrode users, I did not personally assemble these versions.

In all versions I included Eagle *.brd files
No schematics, i.e. *.sch files, because when creating PCBs I work directly on *.brd files.

Lists of elements for a given version are added in the form of an HTML file opened with a browser.

Regards ....

Think about what you are writing about. I am leaving aside contempt and any disrespect.

>>21890622 If you ask the wrong questions you get the wrong answers.

In Category 5 twisted pair (i.e. the Ethernet type cable used in TCP/IP) things are a bit different than in classic signal cables.

🔌 What does transmission look like in a Cat5 cable?
The cable has 4 pairs of twisted wires (8 conductors).
The signal is transmitted as a so-called differential signal (balanced transmission).
Each pair is:
one wire: the "+" signal
the other wire: the "-" signal (inverted)

The receiver analyses the voltage difference between them, not the voltage relative to ground.

⚡ Is there a ground (GND)?

👉 There is no classic signal ground like in audio or RS232 for example.

Ethernet transmission (e.g. 100BASE-TX or 1000BASE-T) is:
symmetrical
galvanically separated (transformers in RJ45 ports)

This means:

the devices do not share a common signal ground
signal "floats" relative to ground
🧲 Why such a design?

It offers several important advantages:

resistance to EMI interference
minimisation of crosstalk between pairs
no problems with potential differences between devices
🧩 And screen / physical ground?
In UTP cables (most common) → no shield → no ground
In FTP/STP cables:
there is a shield (foil / braid)
may be connected to earth
but is not involved in data transmission
🧠 Summary
TCP/IP is only a protocol - physically Ethernet is at work here
Transmission in Cat5 is a differential signal in pairs
No classic signal ground
Transformer separation = no direct electrical connection.

I don't understand where this argument about UTP/FTP and Ethernet transmission is coming from.
My colleague kula350 clearly wrote that he used twisted pair as a shielded signal cable, where one wire from the pair works as a shield and is connected to the system ground. At least that is my understanding.

girowaty4 wrote:

>>21890636 then you learn to read.

I was sharing my knowledge and experience. And that's it. But for you guys, I think it's disruptive to pit on forms, so you got me.

I was referring to "your" AI statement, you will always get the answer you need, a matter of the right prompt.

We have EVO in colour so far very primitive but I encourage you to improve the panels from a visual point of view. Sofcik dedicated to the ILI9341 panel with the new LovyanGFX graphics bibiotech

ejcon wrote:

new LovyanGFX graphics livery

In my opinion this is a very good move in terms of graphics and TFT support.
It is the most efficient library.
It is based on the fast Tft_espi library, which is no longer being developed.

DJCheester wrote:

Version Rev.4.0
- PCB version without SMD components
- The jumpers are made on the top layer of the PCB as tracks, so they do not need to be mounted on the factory PCBs
- PCB version without encoders
- Audio output on Chinch sockets
- TSOP31238 infrared receiver
- Connector 8-pin for LCD display
- 4-pin connector for SD card reader on display
- Note: Do not use two card readers at the same time !!!
- Audio amplifier PAM8403
- Power supply USB printer socket
- MAJSTER XXL software preload
- Dimensions 98.04mm x 87.25mm

Did you keep the pinout from this PCB maybe ?

Greetings ...

I'll add a sofcik still warm for the ILI9488 EVO panel .












ILI9488
Connection to ESP32 S3 N16 R8 // -------------- OLED Display - pin definition -------------- #define SPI_MOSI_OLED 39 // MOSI pin (Master Out Slave In) for SPI OLED interface #define SPI_MISO_OLED -1 // no MISO for TFT display #define SPI_SCK_OLED 38 // SCK (Serial Clock) pin for SPI OLED interface #define CS_OLED -1 // CS residual screen to GND - dice on ILI9488 #define DC_OLED 40 // DC/RS screen on ILI9488 #define RESET_OLED 41 // RST screen on ILI9488

Hello,
i have uploaded to GitHub the new soft for Evo v3.20.14, Link

changes:

The most important issue is the compilation on the new core ESP version 3.3.8
and new libraries for FLAC stations recompiled by me on ESP-IDF 5.5.4
Latest Audio library 3.4.5q (commits 07.05.2026), yes I know this morning 3.4.6 came out, I will probably do an update when it rains again
Compilation of the whole thing as usual checked on Arduino (2.3.6) and on Platformio (pioarduino)

The finished BIN files are for configurations:
1x Encoder, OLED 3.12 SSD1322, FLAC support, AutoStorage function (the radio itself detects the presence of an SD card or switches to LittleFS memory)


VOLUME and MUTE
I have changed the volume handling range. It is now possible to set the value to zero (0) which results in the mute flag being engaged - mute.
Makes it easier to completely mute the radio from a web page where there is no "mute" button.

IR PILOT
Corrected error of learning the power button via the web interface

STATION SELECTION
A solution has been proposed so that after selecting a station from the list, it does not have to be confirmed by pressing the encoder
This is a configurable option in the menu. In the settings as: "Change station from list without click, default:O ff"

OTHER
VUmeter mode 3 - corrected value for right channel
Improved configuration of the TI TAS amplifier
Corrected positioning of the cursor in the station list when calling the list from the IR remote control (from the encoder it worked already correctly in the previous version)
Improved display of station name when using the "Play from URL" function from a website
Minor tidying up of the code


P.S. Was anyone of you at HDM (Hardware Design Masterclasses #6) yesterday in Katowice? I had the opportunity to unknowingly meet someone ?