HED Project

Life/Tech/Ideas

Category: Projects

  • DIY Weekend: resurrecting a dead JBL Go Bluetooth speaker

    DIY Weekend: resurrecting a dead JBL Go Bluetooth speaker

    I had this JBL Go speaker laying around and haven’t touched it since I don’t know when.

    I generally like JBL as the sound quality is amazing and the price is way lower than some super high end brands (like BOSE).

    The only problem with this Bluetooth speaker, and generally with the Bluetooth speakers is that the battery is not easily accessible. This means that when the battery is worn off, then you must replace the whole speaker and buy a new one.

    But, if you want to experiment a little bit and you are not afraid to use a soldering kit, then with less than £10 you can give a new life to your speaker.

    The process is straight forward.

    First you remove the front mesh and reveal the speaker and the screw holes.

    Secondly, you unscrew the screw holes (T6 screwdriver to remove the four 9 mm screws).

    The motherboard is revealed. Unmount the speaker cable.

    The motherboard has only 1 screw. Unscrew it.

    The battery can be seen. It is glued on the case. Inside the battery there is a small “charging circuit” which allows the electricity to pass on the opposite way, from the cable to the battery so it can be charger. Remove the battery cover so this circuit can be revealed. Remove the old battery from it but let all the other cabling as it is.

    Solder 2 cables on the new battery. Red is the positive, Black is the negative.

    Connect the Black with the Negative pole on the charging circuit and the Red with the Positive and check if everything works (you don’t need the speaker to be connected, just press the TURN ON button and the blue led should light on.

    Then solder the cables. (not the best soldering in the world…)

    Start reassembling everything back. Put on the screws, mount the speaker and that’s it! The speaker is alive!

    Disclaimer: Use tape to hide all the naked cables so they won’t touch each other and will not create a short circuit.

    Have in mind, the battery that I used has a way bigger capacity that the previous one but there is a catch. It is thicker and I cannot close the speaker completely. So before buying a new battery make sure that the speaker and the battery fit inside the speaker box.

    The battery I used is a rechargable one for an old NOKIA 3310 phone with 3.6V and 1000mAh (£7.99 from Amazon).

  • Print PDFs (multiple) from Excel with a press of a button

    Print PDFs (multiple) from Excel with a press of a button

    On a previous article, dated 2 years ago, I explained how to automatically print to pdf a sheet, with a press of a button.

    This one is the part 2. It is a tutorial of “how to print multiple pdf files from populated tables” in excel, with the help of VBA.

    I wrote the code in 2018 and since then it has saved me (or the company I work for) a massive number of working hours (or weeks to be more precise).

    (more…)

  • CAD Solutions based on your needs

    cad consultingWe provide high quality CAD solutions to your needs.

    From a non CAD user who wants to learn how to draft, to the CAD user who wants to develop an improved workflow we have the solution. (more…)

  • Air Quality Project (ver. 1)

    DSC07443Introduction

    Due to economic growth, the number of the cars used has increased in the resent years. This accompanies the degradation of air quality, especially in industrialized countries and urban environments due to traffic congestion [1]. In many areas, the traffic related air pollution is the main reason of air quality degradation. The pollutant concentrations are related directly with the duration of the congestion [2]. The World Health Organization (2010)[3] has set the maximum values of pollutant concentrations but in many measurements, these values are exceeded[4].

     The concept

    The concept is to build a low-cost, low power consuming device to monitor the quality of air. (more…)

  • The use of neural networks in R with neuralnet package.

    As the computing power grows the implementation of Artificial Neural Networks (ANN) becomes more and more common in computational systems and programs. Here it is explained what a simple feedforward artificial neural network is and how it is supposed to work.  This article is a demonstration about the R library neuralnet [1a,b] and how it can be applied. (more…)

  • Image Editing Program with R (GUI)

    R is not only for statistics. There is a big progress in packaging creation and there is a vast amount of libraries that let you do many things other than only statistics and data analysis. In this project it is demonstrated a GUI that lets the user make simple edits on photos. The edits user can do is to switch between GRB color mode and Grayscale, edit the Brightness of the image, the Contrast and the Gamma.  I wouldn’t recommend using this script on large pictures that are several megabytes because it makes the system crash. (more…)

  • Handle or create a phone contacts file (“.vcf” format version 3.0[1])

    I thought of this project in order to convert some of my  phone’s contact numbers from their national format (the one with the 00 in front of the number) to the one that the local providers recognize.

    It was a bit challenging as it had to do with things like seeking from information inside data frames, converting data frames, applying changes, save data frames the way user wants etc. Some new aspects also stood on the way. Some of them I cannot figure, until this point, how to solve them.

    The program is very different in its final form than it was thought first to be.  (more…)

  • Rabies animal infections in Greece

    This brief analysis is a demonstration about the number of animal infections with the rabies virus [1] in Greece. The period of interest is between October 2012 and November 2013 where the last infected animals were recorded. (more…)

  • Importing a .csv file with data and using SQL commands to select the data we want and then plot them.

    The program imports data in .csv format. It uses SQL SELECT command with two arguments, it asks the user if it is needed to group some of the data so it may use the COUNT and GROUP BY commands. After the new tables are created, it plots the data and prompts the user to give name to the plot and data.frame so they will be exported as jpeg and .csv respectively.  At the end it asks if there are data that are not numeric so it plots a bar chart instead of line plot. (more…)