Exercising the right to repair - DYI fixing a Volkswagen Polo 6C windscreen wiper stalk (no parts replaced)

I just went on holidays and did a road trip. Because Murphy is always lurking, I was taken by surprise with runaway window wipers. No matter what position of the wiper stalk, these would run in intermittent mode all the time, as long as the ignition would be on.

Building a kiosk for Home Assistant from scrap parts

It is great to have automation in the house providing increments of comfort such as eliminating manual tasks like cleaning the floor, or to aid in managing the energy consumption by turning off lights and appliances which are not in use, or in the safety side, by providing intrusion detection or monitoring the presence of gas leaks or other hazards, and executing the adequate actions.

Ghost switching can be a bitch if your switch is your main circuit breaker

On my way to eat my own dog food, I learned the hard way that ghost switching is kind of the default problem most people will stumble upon when setting up their MQTT switch for the first time.This is not a big deal when you are configuring a single light switch or some other not so critical appliance. But when your switch is in series with your main circuit breaker, ghost switching suddenly gains a whole different level of importance.

The hurdles of fixing a puncture in a Xiaomi M365 scooter

I can say that I am pretty seasoned at fixing bicycle tires. It dates back to my childhood, where numerous times I had to fix the punctures by patching the inner tubes. I still remember the patching kits featuring an assortment of patches of different sizes and shapes, sanding paper, and the rubber cement.

Never had much trouble in separating the tire from the rim, and putting it back together, after having fixed the puncture. The same applies for fixing the tires of more recent MTBs, where upon following the usual technique no major obstacle arises in accomplishing these tasks.

But now, just after a bit over 100 Km into using my Xiaomi M365 scooter, I found a rattling noise in the front tire while riding it. Went on to take a look, and found a thumb tack, fully buried in the tire. As I started removing it, I could hear the air escaping. Decided to leave it there just so that I could ride the scooter back home.

EDF Propelled Hovercraft project - first outdoor test

Following the post regarding the construction of this project, here is finally the first real test:

Performance and handling are very good, as expected.

The most inneficient (and probably the coolest) EV in the world - the electric hovercraft!

This project may well model what an electric hovercraft could feel like to drive. At least from a noise perspective, trust me, it is a pretty solid preview in spite of its small scale!

DSLR Intervalometer - Source code made available in GitHub

For those who remember my work back in the days with implementing an intervalometer for Nikon cameras (yes, in spite of it being rather simple to implement in the camera firmware itself, these larger brands prefer to classify such a feature as premium and make it available only in more expensive DSLRs), I have detailed in the following post, the solution that I have put together:

https://www.creationfactory.co/2012/03/timelapse-intervalometer-technology.html

Car DVR replacement and related shenanigans - part 2

Moving along with more details, like I mentioned in the previous post, the rear camera was reused from the previous installation. This CCD based camera happens to be superior to the basic CMOS camera bundled with the kit. Both in terms of the quality of the sensor itself and its low light sensitivity, but also regarding the lens, featuring a wider viewing angle (important given its role as a backup camera).

The only change however was a substantial improvement in the mounting design, by having added an U-shaped plate in the rear of the camera, with a 4-screw mount instead of the original 2 screws attached to the sides of the camera. This provides a more solid attachment to the L-shaped aluminium parts that in turn stick to the door through an adhesive:

Car DVR replacement and related shenanigans

Introduction

With the vulgarisation of miniature cameras and computing devices of all sorts, technologies that fundamentally serve the mobile industry become cheap enough and available to the point of being useful for other purposes. That is the case of DVR devices for automotive use.

Adding metalurgical capability to a biological microscope - part 2

Like I had previously explained, I was able to obtain from eBay (for a minimally decent cost), just the bare vertical illuminator, which didn't include any accessories. The light house was not an exception. The vertical illuminator consists the main body:

and the light house, which in the original device would be based on a halogen bulb of at least 15-20 Watts:

Adding metalurgical capability to a biological microscope - part 1

Biological microscopes among a few other things, are characterized by the fact that rely on transmitted light rather than reflected light, to produce an image of the specimen.This is adequate for most biological needs because the specimen can either be made thin enough for light to go through, or the medium and/or the specimen itself is relatively transparent to light.

However there are other applications in microscopy where it cannot be assumed that the specimen is transparent or able to be ground to a thickness small enough for light to traverse it. Some materials are opaque even at thicknesses of few microns.

The only solution in these cases is to rely on reflected light. For this to be possible, a different illumination system is required on a microscope. This type of illumination is commonly designated of epi-illumination (as opposed to trans-illumination used for biological observations). This is where a device known as vertical illuminator comes into play (picture obtained from a Olympus BHM manual):

There is nothing like an Enterprise grade solution for a Consumer grade problem

In current times, there is an ever increasing separation between the consumer and physical storage media as a product: with the generalized increase of Internet availability and bandwidth along with massification of server side infrastructures to support storage and other services (e.g. from providers such as Dropbox, Google, Amazon, Microsoft), the user tends to replace the physical storage by the convenience of a cloud storage solution.

Peltier-based dehumidifier

This simple apparatus is a particularly interesting way of demonstrating the principle behind the common household dehumidifier:

The big difference however, lies in the way the low temperature (required for the condensation of the water vapour) is achieved.

Reconditioning a 50+ year old microscope - part 3 - LED conversion

The microscope came with what I believe it must have been the original illumination system:

• a 30 Watt / 110 Volts tungsten bulb (in this case a GE branded one):

Repurposing an old Android Phone

I had an old Samsung Galaxy Y (GT-S5360) which the previous user didn't particularly enjoy for its performance and replaced with a fancier, newer model. With no obvious use to give to the device, I decided to repurpose it for building some kind of a remote monitoring/observation station, and try to find out how it stands out against the harsh outside environment.

While not attempting to simply put the device outside, directly exposed to the sun, rain and extremes of temperature, I made several customizations to better prepare the smartphone turned into a monitoring station.

The first thing I wanted was to have it entirely self-sustainable. As such I bought a 10 watt photovoltaic panel to harvest the energy required by the device:

Drone Recovery Parachute

Failure is a concern that is always present in the operation of a drone. Given the continued increase in acquisition and use of these devices by the general public, safety is of paramount importance. Even the smaller devices of about 2 kg of total weight, in case of total failure at altitude, will fall like a brick and cause damage to whatever is below.

Most configurations such as quadcopters, don't offer any intrinsic redundancy (in spite of having 4 motors). The failure of a single motor will prevent the quadcopter of maintaining level and yaw-locked flight. Some enhanced control algorithms are being developed to provide level and controlled descent in case of single motor failure. Naturally, yaw control is lost, but the on-board inertial sensors and magnetometer are capable of keeping track of the orientation, therefore knowing how to distribute throttle by the surviving motors.

Custom Camera for Image Stacking

On the expectation of obtaining different and better astronomical images I have taken the oportunity to build custom gear for that purpose. The camera itself is an analog Sony CCD HAD 700 TVL based on the Effio chipset. I had it in my quadcopter, and decided to transplant it to this application. It has excelent low light sensitivity (indeed it outperforms the human eye in that respect!), being an interesting candidate for astrophotography.

My task was to adapt an aluminium enclosure to contain the camera sensor and the control keypad:

Listening to Digital Radio Mondiale

The versatility of the Software Defined Radio doesn't seem to have boundaries. While exploring the HF bands, I tried to decode the occasionally received signal from Vatican Radio (http://en.radiovaticana.va/), which as of this writing was the only station I could identify as sometimes transmitting in DRM.

SDR - going higher in the wavelengths

While a 22 - 1400 MHz band coverage is pretty cool (given the price of the hardware), there is still more beyond (and below) these bands. In particular LF, MF and HF bands are interesting for a number of reasons:

Again with the SDR (Software Defined Radio) craze

After I bought my first RTL-SDR dongle (regarding which I made this post covering APT satellite (weather) image reception: http://creationfactory.blogspot.pt/2013/03/receiving-weather-satellite-images-with.html ), it's been sitting on the bench without much use. More recently I found extra stuff that could be interesting to take a look at, such as ADS-B reception (decoding commercial aircraft transponder signals) and less earthly things such as a doing some radio-astronomy, which includes for example trying to detect the 1420 MHz hydrogen line RF signal emitted from within our galaxy (it's a very exact frequency almost as accurate as our atomic clocks).

http://www.rtl-sdr.com/low-cost-hydrogen-line-telescope-using-rtl-sdr/