Solder sucker/pump (the best ever)

I finnaly found the best manual desolder pump, fully made of machined aluminium, made in Japan, The Engineer SS-02 Solder Sucker.

With it’s silicone nozzle, it does work very well.

Can be found on Amazon

USB motion sensor (PIR) to activate monitor

I have an always on net-book for weather forecast (yeah, when paragliding, you need it)
It basically displays a full screen custom web-page with time and date.

Its always on, not really good for the back-light and energy consumption.

So I got the idea of plugging a PIR sensor to wake up the screen when someone approach it.

Take an Arduino Micro Pro (8€ for the Chinese version), a PIR sensor from eBay (2€), a Hammond case (1€) and an USB A male from scrap (0€).

Let’s give a try, with a basic wiring, and this sketch to emulate keyboard thanks to it’s USB HID, the Arduino Micro Pro is a must.

int sensorPin = 10;
void setup()
{
  pinMode(sensorPin, INPUT);
  Serial.begin(9600);
}

void sendWakeUp(void);

void loop()
{
  if (digitalRead(sensorPin) == 1) 
  {
    sendWakeUp();
    while (digitalRead(sensorPin) == 1)
    {
      delay(1000);
    }
  }
  delay(1000);
}

void sendWakeUp(void)
{
    Keyboard.press(KEY_LEFT_CTRL);
    delay(1);
    Keyboard.release(KEY_LEFT_CTRL);
}
And voila!
Quite nice, discrete and works very well, for about 10€/$.
Note: if someone has an idea to send a key other than LEFT_CTRL (as it can be disruptive on a workstation), I’m looking for a solution.

Kobo mini GPS mod with 3D printed case

Introduction

XCSoar is an amazing software for sailplane, hang-glider and paraglider. But laked the proper hardware with the following features:

  • sun readable ( eink)
  • usable with gloves (anything but capacitive)
  • long battery life
  • running android/linux
  • GPS and/or bluetooth
  • dirt cheap (yes 50€/£/$ for this hardware is dirt cheap)

The Kobo Mini (unfortunately no more retailed) appears to be meeting all theses requirements exept the GPS.

Hardware

Component list

You will need for this mod:

  • Kobo Mini reader
  • GPS module with serial output
  • 3D printed spacer
  • switch (optional)
  • extra battery (optional)
  • iron solder (a good one, I use this)
  • solder wire and a piece of flat ribbon cable

Open it up

( By the way, the way Kobo handles the first boot is just crap: no I don’t want to register my device online or anything, just to drag and drop my own ePub books, thanks! )

Backup the micro SD card (command for linux only, sorry, but optional)

dd if=/dev/mmcblk0 | gzip > ~/kobo.img.gz

Solder the MTK3339 GPS breadboard (with a piece of flat ribbon cable such as IDE, Floppy, whatever..)

KOBO to GPS MTK3339 wiring

KOBO - MTK3339
KVCC <-> VCC
TP2 <-> BACKUP (TP2 is just below the battery connector)
RX  <-> TX
TX  <-> RX
GND <-> GND

Don’t forget to cross RX<->TX and TX<->RX (the eternal embedded engineer question, RX TX….)

Just in case you wondered, yes the BACKUP does accept 4.2V (TP2 is battery test point, so not regulated), and not just 3.3V (have a look on the MTK3339 datasheet)

Battery

The original battery of 1000mAh gives from 4 to 6h, which can be quite a limitation.

I swapped to a 3800mAh battery from AliExpress:

I removed the original one and harvested it’s connector for the new one.

To remove the original double side taped battery, use an air dryer or so (warning not a hot air gun, it would be too hot)

The new battery is held firmly with double sided tape and now it last about 20hours of flight: perfect. (but the drawback: it is quite heavy to read in the bed now….)

You can download the STL of the “Kobo mini Case Spacer II” on Thingiverse, made by matbhe (thanks btw).

The STL file is then printed by Shapeways for just 22€ incl P&P, delivered in about a week: very cool!

Take the screws, M1.6x7mm (my 10mm were too long, I had to cut them with a pair of pliers)

All fit snugly, even the original back cover.

Looks nice, no?

Add ON/OFF button to switch the GPS power (a simple SMD switch to the GPS’s VCC)

So I can still use it as a regular eBook without draining the battery and without the blue led blinking in the dark.

Once again, a piece of double side tape holds the GPS module in place.

The switch is accessible by nails as it’s quite recessed.

Add a label for even more clarity.

Software

They are tons of tutorials on the web, I wont discribe it any further, but simply put, it works this way:

Download XCSoar KoboRoot.tgz: http://www.xcsoar.org/download/data.html

And place it on the kobo root file system using any file browser, restart and you are done.

Maps

Then download the map: http://www.xcsoar.org/download/data.html

Download hotspot (probable thermal) as waypoints (wpt format), and set the file in waypoints configuration): http://thermal.kk7.ch/, save all this map file to the correct xcsoar folder.

I created custom map content to have paragliding skyways displayed on XCS:

More detail here: http://www.dotmana.com/weblog/2014/07/xcsoar-generate-custom-maps/

GPS configuration

Configure the GPS to /dev/ttymxc0 at 9600bauds and “GPS waiting for fix” should appear, note that the first fix can take up to 15min (30s later on, thanks to BACKUP power supply to keep the RTC and ephemeris)

And here you are, you have a comp GPS for less than 100€/$/£ for paragliding/sailplane, in about an hour of work.

Next update to come

Integrating a variometer such as leBipBip solar variometer would be perfect, as the firmware is opensource (Git) and it has a serial connection header on the board with NMEA pressure output:

leBipBip mini solar variometer for 89€

leBipBip PCB board has a 0.05″ header with VCC,GND,RX,TX on the top left side (Texas Instrument MSP430 Launchpad value line compatible, only $9.99 )

Links and references

XCSoar forum: http://forum.xcsoar.org/viewtopic.php?f=3&t=1242

Kobo GPS mod on another blog: http://www.extreme-nature.de/?p=9114

M1.6×7 screws: http://www.ebay.co.uk/

Commercial Kobo mod: http://www.goflyinstruments.com/gofly-project-v4/

XCSoar forum about this mod: http://forum.xcsoar.org/viewtopic.php?f=3&t=1404&start=10

Li-ion battery, 3800mAh: http://www.aliexpress.com/snapshot/6132600603.html

http://www.lebipbip.com/

Why FLARM protects it’s radio protocol

The FLARM device is definitely useful for avoiding collision in sailplane.

But the company behind maintains it’s monopoly position arguing that’s it’s safer and cheaper for the users:

We fundamentally believe that our low cost collision warning technology and its licensing procedures are in the
best interests of the sport and its participants.

To ensure safety, full compatibility and interoperability are essential. Experience shows that it is impossible to
be compatible just by following a written specification.

 

This text is just regular company’s crap, to reassure themselves (and the shareholders) they can maintain a high level of monopoly (and profit).

They also state the radio protocol is patented:

FLARM applies for the radio communication between the units a proprietary and copyright-protected protocol

Unfortunately, there is no such thing as copyrighted radio protocol!

Best it when the founder respond this accusation of being obscure and avoid implementation in many hardware device, and in software such as XCSoar:

https://groups.google.com/d/msg/rec.aviation.soaring/daOXteD5ois/IJ1GTbxWPCAJ

The best part it: they managed to impose the device, not only in competition but for any sailplane in France. How comes the FFVV (French Gliding Federation) can make a device mandatory without any alternative?

One person, Hiram Yaeger seemed to have reverse engineered the protocol:

FLARM PROTOCOL VERSION 4 (2008)

 

If interoperability by documentation or standardization would not be possible, even in RF, there would be no GSM, no GPRS, no WIFI, no Bluetooth.

What do you thing you are FLARM? You are just making a simple electronic device broadcasting GPS position in the free RF band, and it’s not even EASA / CAA / FAA certified! (just like any regular babyphone)

Step down while you can and publish this RF protocol, or the community will do it for you sooner or later! (and no update of the 10k units released in the world will save you)

Smartphone headset standards: 2013 and still not one standard!

Believe it or not but are still two headset standards (headphone + microphone) for cellphone: TRRS_Standards

  • OMTP: old Nokia (and also Lumia starting from the 2nd gen[15]), old Samsung, old Sony Ericsson (2010 and 2011 Xperia’s), old Wiko (2012-)
  • CTI: Apple, HTC, latest Nokia, latest Samsung, latest Sony (2012+), latest Wiko (2013+), most Android phones

Skytraxx 2.0 interferences VHF radio

I’m facing this problem: I have a Skytraxx 2.0 (GPS variometer for paraglider) and a Puxing PX-888 VHF ham radio.
When the variometer emits sounds, it triggers the radio whatever the squelch setting is set on.
A quick video of the problem:

While I’m doubtful about the CE certification of this very cheap Chinese radio (a CE sticker is present in the battery tray but doesn’t mean much…).

So, as I’m not planning to change neither the radio or the variometer, I came along with this fix: put aluminum foil inside the variometer case.

Very easy to do, juste make sure the aluminium touches the usb connector when you close it and everything else is well insulated (pin with kapton tape, etc..).

Now the same test with the aluminium shield:

Much better: can use for competitions now, with the mini solar vario leBipBip.

It even seems to improve the time to fix, usualy took 5min and now about 1-2min.

 

CNC 3020T review and customisation

The CNC 3020T from eBay or Alibaba is quite good for the money (700$/600€ inclVAT).

I use it with LinuxCNC on a dedicated computer with parallel port (hard to find nowaday).

For me the hardest part was designing and typing the G code manually to get this:

But it laked some feature such as spindle control from computer, so I made this mod.

From the Spindle_drive_mod.pdf you can see by adding an optocoupler, you can control the spindle ON and OFF:

On the stepper the board YOOCNC T62-3AX, extra optocoupler are present on the input side, so, just take the first one on the left (the right one is used for the Emergency Stop):

and place it on the free place, without soldering the pin 3 and 4

The pin 3 and 4 should be lifted and insulated from PCB with tape (Kapton) and attached to pin header:

On the spindle motor board, add pin in the free slots:

And just run 2 wire from the Stepper board to the spindle board (respect polarity):

Then just configure Step

More to come: RPM speedometer and X-Y home switch.

Arduino Tracto Turtle

Un petit montage Arduino, le robot Turtle de DFRobot, montage assez simple et connexion de quelques capteurs.
Au programme :
- LED éclairage avant blanche
- LED signalisation obstacle arrière rouge
- détection obstacle avec capteur ultra-son
- bipper lorsque la marche arrière est enclenchée
- récepteur infra-rouge pour prise de contrôle par télécommande

L’ensemble du montage m’a pris 2h30, programme inclus. Je comprends l’engouement pour ce type de plateforme, c’est impressionnant d’efficacité pour s’amuser ou prototyper quelque chose de fonctionnel.

Vous voulez vous lancer ? Il y a plein de tutos sur le net, plein de boutiques en lignes, et si vous avez des questions, n’hésitez pas en commentaire.

Lave vaisselle PROline dwp5012wa (domestic dishwasher) plus de chauffage

Après 4 ans, l’obsolescence programmée à frappée mon lave vaisselle, et comme j’aime mon confort mais ne veux pas dépenser 300€ pour en changer, je décide de l’ouvrir.

Comme si changer les capas de la carte mere de mon pc suffisait pas!

Le problème étant plus de chauffe.

Dans l’ordre:

  • Ouverture et vérification de la résistance de l’élément chauffant (28ohms pour 1800W)
  • La connectique (pas trop oxidée)
  • On enleve la carte éléctronique
  • Check du relais (bobine et contact)
  • Check de la diode de roue libre
  • Check du transistor MOS de commande = HS

Heureusement que j’avais ce genre de transistor en stock (merci le BipBip)

Un coup de fer à souder plus tard, et hop, un lave vaisselle reparti jusqu’à la prochaine pièce sous dimensionnée qui coute 0.006€, merci PROline, merci Darty, merci la Chine pour tout votre électroménager jetable!

(oublié de préciser que j’avais coupé la piste du buzzer piezo dès son achat, car sinon vous casses les oreilles au moindre appuis de boutons)