Entries tagged 'cat:Electronics'

Phones people say don't exist but they do

Some people say things like: Phones should have bigger batteries, I don't care how thick it is. Or: Why aren't there any smartphones with screens smaller than 5 inches anymore? Or: There used to be a wider variety of phones; I'm missing keyboard phones/rugged phones/phones without a bunch of bloatware/etc. I think it is a very small group of people who feel like this strongly enough to say it. But I keep stumbling over such comments and I notice them because I have sometimes felt the same. And there's some truth about some of it. The most popular phones are all large and thin with privacy-invading bloatware that you can't uninstall and often with other malware pre-installed. They don't have keys on the front and you can't simply switch out the battery. But there is a bigger variaty of phones than there has ever bean. If you're missing a certain feature in your phone and can't find one that has it, you probably haven't looked far or long enough. I'd just like to mention a few manufacturers of not entirely mainstream phones and then maybe I'll make individual entries about some of them later with more information.

Keyboard phones

Notable options are:

F(x)tec: Flips open, keyboard in the style of late Nokia keyboard smartphones, best for thumb-typing, currently the first version is only available used and the newer version is currently shipping to Indiegogo backers. So it should be available without a long wait from the web shop soon.

Planet Computers: Different variants available, older ones are clam-shell, the latest is trying a new mechanism that leaves the touchscreen on the outside and usable when the physical keyboard is closed. Keyboard in Psion Series 5 style, best for table typing.

Unihertz: Clones of late Blackberry keyboard phones, screen above keyboard, for thumb-typing.

A used phone. Because you can still get a blackberry if you like. A few weeks or months from now you probably wouldn't be able to tell the difference between you almost new one and a refurbished one anyway. It's cheaper, you have more devices to choose from and it's better for the environment (whatever your definition of that may be). Did I miss or forget an option?

Phones with small screens

Uniherts also has started to fill this gap. Or you can get an older phone, maybe a used one. A few weeks or months from now you probably wouldn't be able to tell the difference between you almost new one and a refurbished one anyway. It's cheaper, you have more devices to choose from and it's better for the environment (whatever your definition of that may be). Did I miss or forget an option?

Phones with large batteries

If that's your one important requirement, you have many cheap phones that claim to have batteries with around 10 Ah (yes, 10.000 mAh if you prefer to see read more zeros) to choose from. Some manufacturers that I don't know anything about are: Yess, Gionee, Blackview, Ulefone. Ulefone seems to have several current models to choose from and I know somebody who is happy with theirs, whatever that tells you. I'm sure there are more brands of phones with giant batteries. But I'm personally happy with the 2 to 3 days I get out of my regular phone. I only complained about this when phones would at most last for one day without getting charged. If you're content with a battery with a capacity of around 6 or 7 Ah, you have even more to choose from and that range has actually started to enter the mainstream phone market (Huawei, Samsung, Asus, ZTE, …). You'll easily find some if you look for them. But many still don't think of searching for one. I guess this has been more of an issue 10 years ago, where phones needed more power to come through a day while at the same time no smartphones with big batteries existed. Getting an external battery that clips to the back of your phone has been more of a thing back then. That's still an option if such a product exist for your phone or you really love duct tape.

Headphone jacks, removable batteries, hardware buttons below the screen, ...

How about getting a used phone. A few weeks or months from now you probably wouldn't be able to tell the difference between you almost new one and a refurbished one anyway. It's cheaper, you have more devices to choose from and it's better for the environment (whatever your definition of that may be). Or at least I read that somewhere a few minutes ago. There are new phones with current hardware that haven't given up on these concepts. But none that I care to mention and the choice of phones with current hardware and easily removable batteries or hardware more than one hardware button below the screen doesn't appear to be good. Did I miss one?

But what about software? Security updates, free software, Google-less Android, privacy-respecting operating systems

Well, it would certainly make choosing and setting up a phone easier if you don't care about those things. But the FOSS community is producing images for many phones that otherwise would only run an Android built by the manufacture or carrier with all the usual insults like bloatware, pre-installed malware and other privacy-invading components. Using an older smartphone (maybe not a Nokia Communicator/Nokia 9xxx, but like maybe 10 years old) with current free software is certainly an option.

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Poly Keyboard

Here is another project idea I never really started working on: A computer keyboard that has a small LCD in each key cap. I'm convinced that there are legitimate use cases. After all, the function of the keys changes according to context. Different applications have different shortcuts, when I press and hold the Ctrl or Super key, the whole layout practically changes. Most people don't remember useful keyboard shortcuts, if they try to memorise them in the first place (if the learn about them to begin with). It would be nice to have the markings on the keys reflect their role. In some special applications, like video editing, a completely custom keyboard layout would be useful (a cheap alternative to byuing a custom video editing interface input device). In computer games, only the useful keys could light up, as well as display what they do (which depends not only on the game, your custom layout, the current situation in the game, as well as what happened earlier in the game, e.g. what items you have in your pockets). You might want to write in different languages and need different keyboard layouts at different times. You could have icons or descriptions of key functions be displayed whenever you hold a modifying key, to see which shortcuts are available. You could have a second keyboard with an additional layout to give you access to frequently used functions, and have the keys display the relative application icons or describe what they do. And it would just look cool.

The idea has been in my head for years. I even board the electronics to build a few keys to try it out. But I never build one because I think it would have been too much work on the side to get it done well, considered I come by very well without one. Now I learned that somebody else has built a keyboard very similar to what I had/have in mind. To be honest, I never really get very deep into the keyboard building community to know whether a keyboard like this already existed. I think when I had the idea I didn't even know how big the mechanical keyboard fan community is and that DIY builds are such a big thing.

The project I stumbled over is the Poly Keyboard by thpoll. Here is an article about it in the Keyboard Builder's Digest, here is the Github repo. Apparently (according too the article) it isn't the first of its kind. But it's the only one I've seen.

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PIN Changer

I had to change the default PINs of over 200 SIM cards once. And such a situation could arise again. So I've built a PIN changer in which I just have to insert the card, wait a few seconds and it's done.

The Card Slots

SIM cards in their natural form factor aren't as fiddly to handle as they are in the form factors most people know, which is Mini SIM, Micro SIM and Nano SIM. Classical SIM cards are the same size as other smart cards. I found a card slot with an end switch on eBay. I like it when I find industry grade parts for cheap on eBay as part of some remaining stock. Additionally I've used a slide-in mini SIM slot and another, separate end switch from my parts collection in case I to change the PINs of smaller cards.

The Baseband Processor

Other parts that I've used is an Arduino Nano sized Arduino Nano nearly-clone and an A6 modem module. There are many similar modem modules designed around different but similar ICs. Many of them are cheap and widely used for DIY IoT projects. So example code for the Arduino and other help can be easily found on the web. I don't know why I went with a module with an A6. But it works fine and there are an Arduino library for it as well as cheap modem modules with it available.

(tba:voltage supply)

The Controller

Yes, Arduino may be kind of the noob go-to board and could look up how to use microcontrollers on their own finally and even if I don't want to I could finally start to use ESP32s like everybody else. But I know Arduinos and by now I'm familiar with it and it works, so, whatever. Arduino Nano is kind of my go-to form factor now because they have integraded USB, are Uno compatible and small. Unless I need more or something very specific I use Arduino Nano almost-clones with USB-C port.

The Code

The code is a real mess. It had been a long time since I had written any even halfway serious C. It may have been the first time, actually. The sketch surely is very easily improved by somebody who knows what they are doing. I intended to improve it myself. But the project is currently abandoned and The code is doing what it should in a way I initially had in mind as the goal. But I'll leave the mess of the comments in for the case that somebody wants to make out what I was thinking.

// Funktionen umschreiben: Beim Empfangen wird erwartet: 1. der AT-Command zurück, 2. eine Antwort, 3. OK oder ein ERROR.
//                         Daher sollte abgefragt werden, bis entweder OK oder ERROR kam oder 20/50/9001(?) Abfragen lang weder OK noch ERROR an kam.
//                         Die Antwort in Variable speichern? Naja, String zurückgeben halt.
//                         Antworten, die mit "^" anfangen brauchen nicht gehandlet zu werden, da keine Kommandos, die mit AT^ beginnen gesendet werden.


SoftwareSerial A6MODULE(6,7);
int intled = 13; // Internal LED
int successled = 8; // Green LED
int failled = 9; // Red LED
int wrongpinled = 10; // Orange LED

boolean debug=true;

//String commands[5] = { "AT", "AT+CPINC2", "AT+CPIN?", "AT+CLCK=\"SC\",2", "AT+CPIN=\"3010\"" };
//int command = 0;

const byte maxmsglength = 32;
char received[maxmsglength];
boolean newData = false;
String response = "";

int i=0;

To check/do:
1  AT: OK?
2  is PUK required - abort
3  are less than 3 PIN attempts left? - abort AT^CPINC=?
4  is PIN disabled
       5  enable it: 0000
6  is PIN enabled
       7  unlock
8  is card unlocked
       9  change PIN: 1996
              was PIN wrong - report and leave it

void setup() {
  pinMode(intled, OUTPUT);
  pinMode(successled, OUTPUT);
  pinMode(failled, OUTPUT);
  pinMode(wrongpinled, OUTPUT);
  // All LEDs turn on at the beginning and stay on during the wait period at the beginning, then turn off before communication with the A6 module starts.
  digitalWrite(intled, HIGH);
  digitalWrite(successled, HIGH);
  digitalWrite(failled, HIGH);
  digitalWrite(wrongpinled, HIGH);
  digitalWrite(intled, LOW);
  digitalWrite(successled, LOW);
  digitalWrite(failled, LOW);
  digitalWrite(wrongpinled, LOW);
  digitalWrite(intled, LOW);

void loop() {
  if(getfroma6("OK")) {
//    sendtoa6("AT+CPIN?");
//    if(getfroma6("+CPIN:SIM PUK")) { fail; }         // If the required password is PUK, abort.
//    sendtoa6("AT+CPIN?");
//    if(getfroma6("+CPIN:SIM PIN2")) { fail; }        // If the required password is PIN2, abort.
//    sendtoa6("AT+CPIN?");
//    if(getfroma6("+CPIN:SIM PUK2")) { fail; }        // If the required password is PUK2, abort.

    getfroma6("+CPIN:SIM PIN");                      // The last non-empty response will be stored in the global response variable. Problem with this: If the A6 module sends an unsolicitated message before the response to the CPIN command, nothing gets done and the card needs to be re-inserted again.
    if(strcmp(response, "OK") == 0) {                // If already no PIN is required

//      sendtoa6("AT+CLCK=\"SC\",2"); // Ist PIN-Abfrage eingeschaltet? Oder ist es "SC"?
//      if(getfroma6(???)) { PIN-Abfrage einschalten mit 0000; }

      d("I don't know how to enable the PIN.");

    if(response = "+CPIN:SIM PIN") {                 // If the required password is PIN, continue.
      if(getfroma6("^CPINC: 3")) {                   // If not exactly 3 attempts are left, abort. (should be larger than or equal to 3, shouldn't it?)
        sendtoa6("AT+CPIN=\"0000\"");                // Freischalten mit 0000
        if(!getfroma6("OK")) { fail; }               // If that was not the right password, abort.
        sendtoa6("AT+CPWD=\"SC\",\"0000\",\"1996\"");// PIN ändern
        if(getfroma6("OK")) { Serial.println("Looking good."); }

//      sendtoa6("AT+CMGD=0,4"); // Should delete all SMS
//      if(getfroma6(???)) { ; }
        d("I don't know how to delete SMS.");

        if(getfroma6("+CPIN:READY")) {

          digitalWrite(successled, HIGH);
      } else {                                         // If not exactly 3 times left

void fail() {
  digitalWrite(failled, HIGH);               // Turn red fail LED on and ...
  d("Something failed! Ending programme.");
  while(1);                                  // ... don't do anything anymore.

void wrongpin() {
  digitalWrite(wrongpinled, HIGH);           // Turn yellow LED on and ...
  d("Wrong PIN! Ending programme.");
  while(1);                                  // ... don't do anything anymore.

//boolean getfroma6(char str[32], char str1[32], char str1[32], char str1[32], char str1[32], char str1[32]) { // Returns true if the passed (expected) message was received, false if anything else was received.
boolean getfroma6(char str[32]) { // Returns true if the passed (expected) message was received, false if anything else was received.
  boolean asexpected = false;
    for (i = 1; i < 9; ++i) {
//    d("d1 "+response);

    if(received[0] == '\0') {                            // If the received message is empty
    } else {
      response = received;
    if(strstr(received, "ERROR") != NULL) {              // If the received message contains "ERROR"
      d("Received an error: "+response);
    if(received[0] == '+') {                             // If the received message starts with a "+" sign
      d("Reseived response: "+response);
    } else {
      if(strstr(received, "OK") != NULL) {               // If the received message is "OK"
        d("Received OK.");
        asexpected = true;                               // Also treat OK like the expected message. No unexpected OK should ever be sent from the A6 module. So this is fine. No, it is, really.
//        if(asexpected) { return true; }
      } else {
        if(strncmp(received,"AT",2) == 0) {              // If the received message starts with "AT"
          d("Received AT: "+response);
        } else {                                         // For any other received message
          d("Received: "+response);
    newData = false;
    if(strstr(received, str) != NULL) {
      d("Received expected message: "+response);
      asexpected = true;
  if(asexpected) { return true; }
  return false;

//void handleresponse() {
//  response = received;
//  if(received[0] == '+') {
//    d("               Response: "+response);
//  } else {
//    if(strstr(received, "OK") != NULL) {
//      d("               It's okay.");
//    } else {
//      if(strncmp(received,"AT",2) == 0) {
//        d("               I've sent: "+response);
//      }
//    }
//  }
//  newData = false;

void receivelinefroma6() {
  static byte counter = 0;
  char rc;
  received[0] = '\0';

  while (A6MODULE.available() > 0 && newData == false) {
    rc = A6MODULE.read();

    if (rc != '\n') {
      received[counter] = rc;
      if (counter >= maxmsglength) {
          counter = maxmsglength - 1;
    else {
      received[counter] = '\0'; // terminate the string
      counter = 0;
      newData = true;

void sendtoa6(String command) {
//  Serial.println(command);
  d("Sent: "+command);

void d(String line) {
  if (debug == true) { Serial.println(line); }


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All Those Bike Attachements

I think bicycle accessaries are of these things that developed over time past the point where it would have been sensible to rethink how things are done. I think it would make sense the rethink how all those bike attachments are integrated.

A bicycle without any attachments is already nice. It can be used without them and none of the things are necessary all the time. So it can make sense to have them detachable. But probably most people use their bike mainly for one thing - transportation, mountain-biking, sports - and need the same combination of attachments most times the bike is used. (Minus the lights when it's not dark.) I think it's rather peculiar that people buy, attach and use all these extras without questioning the crowded state of their bicycle frame. Let me list the things that I find useful myself.

  • Bell (*)
  • Front light (*)
  • Back light (*)
  • Phone/GPS holder
  • Phone charger
  • Action camera
  • Remote for indicators (in helmet or jacket/shirt)
  • Horn

(*): required by law when driving on the street

So, in this configuration, when you get back from riding your bike, you have to turn off the front light, turn off the back light, turn off the helmet indicator, turn off the indicator remote, check the charge of the front light, the back light, the phone charger, the GPS, the helmet, the helmet control, the horn and the action cam, detach the things that need charging, bring them in the house and plug them in for charging one after another. You may also have an electronic lock, additional front lights, a breaking light, the remote control for the breaking light and a headlamp. Half of them still have a micro USB port and none of the batteries last for dozens of rides (unless you ride mostly when it isn't dark). Sure, that comes with the benefit of having these devices, people seem to think. But they don't do all of this when they get out of their car. Because it wouldn't make sense to have a separate battery for every electronic device in a modern car. Neither does it make sense on a bike.

It would be nice to have a central battery for everything on my bike and a single on/off switch. But I don't use it enough to see me investing in building it myself. Because if I'd do it, I'd want it to be safe and secure in any weather, look good and not be too clunky or heavy. So I'd have to invest time.

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USB/Serial PWM Fan Controller Using an Arduino

I wanted to be able to control the speed of the fans in my big NAS, Fred, individually. Even though the mainboard in use has five PWM fan connectors, the chipset can only control the speed of all fans together. There are probably good fan controllers commercially available that solve this problem better than I did. But they seemed overpriced and it seemed like a fun learning project for me.

The fan controller that I made uses an Arduino Nano clone that listens to it's serial port, waiting for a command to change the speed of a fan. When a command is recognised the continuous PWM signal for that fan is changed accordingly. It's possible to control up to six fans this way with an Arduino Nano. I'm only using three though since I only have three fan groups that need to be controlled separately.

The Arduino sketch/C code for the Arduino Nano that I used is as follows.

//fan speed sensor wire attached to digital pin 2 with a 10kohm pullup resistor
//fan PWM control wire attached directly to digital pin 9

#include <PWM.h> //include PWM library http://forum.arduino.cc/index.php?topic=117425.0

volatile int half_revolutions1; //allow half_revolutioins to be accesed in intterupt
volatile int half_revolutions2; //allow half_revolutioins to be accesed in intterupt
int rpm1; //set rpm as an integer
int rpm2; //set rpm as an integer
int pwm=255;
const byte numChars = 5;
char receivedChars[numChars];

boolean newData = false;

void setup()
  InitTimersSafe(); //not sure what this is for, but I think i need it for PWM control?
  bool success = SetPinFrequencySafe(9, 25000); //set frequency to 25kHz
  pwmWrite(9, 51); // 51=20% duty cycle, 255=100% duty cycle

  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  analogWrite(5, 170);
  analogWrite(6, 255);
  pinMode(2,INPUT_PULLUP); //set RPM pin to digital input
  pinMode(3,INPUT_PULLUP); //set RPM pin to digital input
  half_revolutions1 = 0;
  rpm1 = 0;
  half_revolutions2 = 0;
  rpm2 = 0;


void loop()
  sei(); //enable intterupts
  attachInterrupt(0, fan_rpm1, RISING); //record pulses as they rise
  attachInterrupt(1, fan_rpm2, RISING); //record pulses as they rise
  cli(); //disable intterupts

  rpm1 = (half_revolutions1/2)*60;


  rpm2 = (half_revolutions2/2)*60;


  rpm1 = 0;
  half_revolutions1 = 0;

  rpm2 = 0;
  half_revolutions2 = 0;

  pwm = 255;

void fan_rpm1()
  ++half_revolutions1; //increment before returning value

void fan_rpm2()
  ++half_revolutions2; //increment before returning value

void recvWithStartEndMarkers() {
    static boolean recvInProgress = false;
    static byte ndx = 0;
    char startMarker = 's';
    char endMarker = '\n';
    char rc;
    while (Serial.available() > 0 && newData == false) {
        rc = Serial.read();

        if (recvInProgress == true) {
            if (rc != endMarker) {
                receivedChars[ndx] = rc;
                if (ndx >= numChars) {
                    ndx = numChars - 1;
            else {
                receivedChars[ndx] = '\0'; // terminate the string
                recvInProgress = false;
                ndx = 0;
                newData = true;

        else if (rc == startMarker) {
            recvInProgress = true;

void processCommand() {
    if (newData == true) {
        switch (receivedChars[0])
            case '1':
                receivedChars[0] = '0';
                sscanf(receivedChars, "%d", &pwm);
                analogWrite(5, pwm);
            case '2':
                receivedChars[0] = '0';
                sscanf(receivedChars, "%d", &pwm);
                analogWrite(6, pwm);
            case '3':
                receivedChars[0] = '0';
                sscanf(receivedChars, "%d", &pwm);
//            default:
//                Serial.println("I don't know what that means.");
        newData = false;

Well, how should I put it? It works, usually.



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Zeo Mobile Teardown

2015 habe ich mir mal ein Zeo Mobile genauer angeschaut und im Schlafhacking-Blog darüber geschrieben.

Hintergrund: Das Zeo war ein Gerät ("war, weil es schon lange nicht mehr hergestellt und vertrieben wird), das anhand von Bewegungsdaten, EOG und EEG ein Schlafprofil des Trägers eines Stirnbandes erstellte. Es war wahrscheinlich das erste Gerät seiner Art, das diesen Einsatzzweck einfach benutzbar, mit cloudbasierter Software für Normalconsumer und - dafür, dass es quasi kein richtiges Konkurrenzprodukt gab - ziemlich günstig, bedient hat. Ich weiß gar nicht, woran der Hersteller, Zeo, Inc., ehem. Axon Labs) gescheitert ist. Er war dem heutigen Trend so weit voraus und hat alles geboten, was den Benutzern von heutigen, ähnlichen Geräten für den Zweck der Verbesserung der Schlafqualität wichtig ist, dass man ihn eher als Innovator als als seiner Zeit voraus bezeichnen kann. Anyways, es gab/gibt hauptsächlich zwei Geräte: Das Zeo Bedside, bestehend aus Nachttisch-Empfangsgerät, Kopfband, USB-/serieller Schnittstelle und Windows-Software, und das Zeo Mobile, ein Bluetooth-fähiges Kopfband mit Smartphone-App. Für ersteres wurde von einem (Ex-)Entwickler des Gerätes eine modifizierte Firmware (Version 2.6.3R) in Umlauf gebracht, die es ermöglicht, über USB die Rohdaten der Sensoren zu empfangen und so eigene Software zu benutzen. Damit hat während des kommerziellen Untergangs Zeos nicht nur er meinen Respekt gewonnen, sondern auch das Zeo Bedside neue Einsatzmöglichkeiten und eine Fan-Community von technik-interessierten Klarträumern. Für das neuere Zeo Mobile gibt es zwar auch eine Android-App, mit der man das Gerät ohne Konto auf dem nicht mehr existeierenden Zeo-Server weiterbenutzen kann, aber aus dem einfachen Grund, dass es nicht einfach möglich ist, Rohdaten aus dem Gerät zu bekommen, haben die Zeo Mobiles bei weitem nicht die Beliebtheit unter Hobbyisten, die die wenigen noch in Umlauf befindlichen Zeo Bedsides genießen.

Also, 2015 habe ich mir mal ein Zeo Mobile genauer angeschaut und im Schlafhacking-Blog darüber geschrieben: Zeo Mobile Teardown

Eigentlich wollte ich noch einige weitere Links hier einbauen, wie zum Beispiel zu der Entwickler-Webseite und zu ein paar interessanten Software-Projekten, die die Daten der Rohdaten-Firmware des Zeo Bedside nutzen. Leider kann ich die Firmware selbst nicht mehr finden und auch die relevanten Informationen sind nur noch im Internet Archive zu finden. Dort sind die Software-Downloads aber nicht archiviert, weshalb sich der Rest erübrigt. Sehr schade. Ich hoffe jemand wird die Sachen noch mal öffentlich zur Verfügung stellen. Ich habe sie leider nicht bei mir, weil ich nie ein Zeo selbst bespielt habe.

Vielleicht nehme ich den letzten Absatz wieder zurück. Hier ein paar URLs, die oben vielleicht fehlen (habe gerade keine Lust, sie in line zu bringen):

  • https://www.gwern.net/docs/zeo/index
  • https://www.gwern.net/docs/zeo/firmware-v2.6.3R-zeo.img
  • https://www.openyou.org/2013/06/11/zeo-firmware-and-raw-data-api-on-openyou-github/
  • http://eric-blue.com/2013/06/09/life-beyond-zeo/
  • https://github.com/evsc/zeoLibrary
  • https://github.com/openyou/zeo-firmware
  • https://github.com/openyou/zeo-raw-data-api
  • https://github.com/openyou/zeo-android-api
  • https://www.klartraumforum.de/forum/showthread.php?tid=9523
  • http://www.sleepstreamonline.com/rdl/
  • https://web.archive.org/web/20120422001938/http://sourceforge.net/projects/zeorawdata
  • https://web.archive.org/web/20110307193953/http://sourceforge.net/projects/zeodecoderview
  • https://sourceforge.net/projects/rxtxlibrary/files/rxtxlibrary/
  • https://sourceforge.net/projects/zeolab/
  • https://sourceforge.net/projects/zeolib/
  • https://web.archive.org/web/20120924070141/http://developers.myzeo.com/raw-data-library/
  • https://www.klartraumforum.de/forum/forumdisplay.php?fid=29 (Inhalt nur eingeloggt sichtbar)
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No smart home for me, thanks.

I don't think I'm going to set up anything that could be considered smart home tech for me. There are such fun projects in it and it would be very satisfying to be able to control some things remotely (that is, I'd decide on and be able to change the interface) but it would also be yet another never-ending project for me. I have never planned to install anything of that kind but I already have so many ideas about what I would do if I would go smart home and how I'd set things up. Let's leave it at that. I have enough too many unfinished project already.

For example I have those universal keypads that were made for numeric keypads (+ a fey extra keys) of industrial machines. I have at least a dozon of them, maybe two. They are great: Good quality in every aspect, nice hard click, sturdy, customisable (buttons can be switched out or replaced by blank covers) and a simple matrix connector. It would ne great to have one of these next to every door, in or on every table, at the bedside, and maybe one or two non-stationary ones that would control everything that could be relevant from the location of each terminal.

Every terminal would have a micro controller connected to a network. I could update those controllers all at once with new firmware. The keypads would have several modes from where I could control devices and the lights (including color, at least in one room). Also for my blinking light projects and mood light that would be a nice way of turning on and off exactly those lamps, effects and glowing pictures that I want at taht moment.

But I won't do it. That's a decision.

PS: Does anybody want some great small keypads for DIY use?

Edit: I remember that I, when I previously talked about this topic, said that I don't start with this because the value I see it bringing to my life isn't large enough. I said that the one thing that could convince me that it's worth investing money and time into smart home tech would be a really very reliable way of sensing presence in a room as well as somebody approaching the entrance to a room. Basically, if I the music or podcast that I was currently playing on my PC or phone would automatically be played in the room I'm currently in but not in any room I'm not in, except when I was about to walk into another room, then I'd maybe get in. If this would be really really reliable and affortable, then I'd reconsider my decision. Thermal based motion sensors aren't good enough for this. I'd probably need a dozen of them in each room. (Looks like I saved a dozen of the wrong things from being scrapped.) And to customise the software for my home would probably a small project on its own. I don't know of another sensor that could do this that wouldn't require me having at least some sort of device on me all the time.

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Another never finished electronics project: my electronic typewriter that would make a very nice retro style terminal but isn't one

Background story: I wanted to park my car at a certain small parking lot that's usually pretty full. I was lucky: There was a free spot. Or so it seemed. As I drove up to it I saw there was something lying in the middle of the free spot. Looked like somebody got rid of some scrap there. I got out and honestly I wanted to put the stuff to the back of the parking spot under the tree that was there. If somebody decided not to bring their scrap to the right facility for free for some reason that doesn't make me responsible to pick it up and bring it there, I thought. But when I saw that it was an almost new looking electronic typewriter, I quickly decided to take it with me instead. It was a Triumph Adler Gabriele PFS. As I read somewhere it came out in the late 2000s or early 2010s. So not as vintage as the name typewriter may sound. But definitely some old piece of tech that is obsolete now but has a nice character and conveys a feeling from a certain time. That and the fact that I've never had or even used one made me add it to my collection of retro tech (that I've never before called collection because it doesn't really deserve that name).

Back at home I examined and tested it and I would have cleaned it, but there was nothing to clean. The case of the internal transformer was cracked and the outer case had a deep scratch at the corner where the transformer is. Everything was working fine except for the 2.8" diskette drive. The rubber band had long been degraded. But the bigger problem was that the main motor didn't do anything else than heating up very quickly. I couldn't find a replacement easily and still couldn't find a good replacement when I searched more thoroughly later. So I've replaced the drive with an emulator so I could use SD cards instead of diskettes. That not only has the advantage of working right now but also of using a medium that is more reliable being handled by my clumsy self and available easily. New 2.8 " diskettes would cost more than SD cards and couldn't hold nearly as many and long documents.

Before the drive emulator worked I had to work a bit with the developer of its firmware. I was lucky that I had a logic analyser and that the project was actively maintained by a developer who cared for adding support for my typewriter. The interface for that model of Mitsumi QuickDisk drive was already supported before. But the reverse engineered parameters, especially the timing was just not exact enough for my Gabriele.

Well, that's the state the machine is in right now. I can use it, I can save documents to SD card, I can't read the original diskettes and I can't read the documents on a PC or create documents for the typewriter on a PC without writing software for it first. I'm not using it for anything. The best thing I could come up with on what I could/would want to do with it is to add an interface that allows me to use it as a text printer. It has a printball with all important characters (no ASCII line art though, sadly) and maybe completely switch out its software to give the machine a new purpose. The easiest way for me would probably be to ignore all the electronics that are already inside and add a microcontroller that handles the LCD, print head and communication with the outside. I still wouldn't have any use for that though. So additionally I would turn it into a serial or telnet or SSH terminal, maybe all three. That would be more fun. Vintage look, vintage keyboard, vintage feel overall, a display that is subpar because it's old technology but still good enough to do its job, and the ability to print text on paper. Yeah, that would be fun. But I still wouldn't really have a use for it. I have a laptop that can do that job better and the keyboard of the typewriter doesn't have as many keys as I'd want it to have.

So, I'm not going to do it, or anything else with it. Maybe some day. Or none. Got any better/additional idea what I could do with it?

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USB Volume Control Knob

Volume control used to be a lot more responsive, quick and simple when the used potentiometers (analogue knobs or wheels). Just reach to the knob and the volume is at 0 or 100% almost instantly. No key combinations, no deactivated function keys, no switching tabs, no delay (!), no pressing the same botton multiple times or holding it down. I miss that.


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"RGB LEDed" Shop Sign

Found this old shop sign on ebay Kleinanzeigen. Idk, I just wanted to have it. Picket it up for 10 € since it wasn't far from me. Put some RGB LEDs and an Arduino inside, used some sample RGB LED sketch, Robert is your uncle. (tbc)

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