Archive for the ‘Uncategorized’ Category

Retour vers le futur

Allez, zou, pour une fois voici une publication en français ! Cà fait un moment que çà me grattouillait le clavier de composer dans ma langue maternelle, et je vois au moins deux bonnes raisons de faire une entorse à ma politique de publication. Soyons réalistes, l’anglais est une langue universellement comprise par les technophiles, […]

PCBs (Part 3)

Part 1, 2, 3, 4 Once we have our gerber files ready, it is time for “printing” the PCB. For a long time (and a long time ago) I used single sided coated copper Bakelite boards. Then I would copy the circuit  on copper using a special permanent ink pen (in negative) and immerse the […]

PCBs (Part 2)

Part 1, 2, 3, 4 Let’s exercise the tip and tricks that I shared with you in my latest post. Here are the requirements for this subject: Project: As a one idea per minute person, it was hard for me to stick to one project and one design. However, I had in mind the project […]

Current generators (Part 1)

Part 1 Here starts a new series of post dedicated to current generators. As usual, the idea is to describe working experimental prototypes that feature few components and quite good performances. Current generators can be found in various applications such as battery chargers (advanced ones, aka multiple stages or intelligent battery chargers), LED drivers and […]

Direct Digital Synthesizer (DDS) (Part 8)

Part 1, 2, 3, 4, 5, 6, 7, 8, 9 As seen before, the proposed DDS design has its own limitations. The main restriction is caused by the limited frequency from Arduino: 16 MHz for 5 V supplied platforms such as the UNO, and lower frequencies for 3 V supplied platforms such as the Fio. As a consequence, the higher the requested DDS frequency […]

PLD (Part 6)

Part 1, 2, 3, 4, 5, 6 The PLD features a multipurpose connector mainly dedicated to plugging sensors. This video shows how easy it is to configure a PLD an run an application for  monitoring temperatures. Back us on Kikstarter … Do you want to know more about HL2, HL2 Panorama and HL2 PLD ? Check this video Thanks for watching

3D Printing (Part 12)

Part 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 3D printing can be tiring for the nerves… For a week or so, I was enable to print full size parts without enduring severe problems such as splitting layers, irregular faces and even gaps. Here is an illustration of the prints before the fix (on top) and after the fix. The first layers […]

Undocumented commands and functions

Long time ago as I was learning about George Boole  algebra I immediately though about using a (hidden) sequence of button presses to lock and unlock safes, doors, etc.  In addition to setting arbitrary sequences of button presses, I had the idea of taking into account the time spent on pressing each button which would […]

What a shame !

I recently reactivated my Facebook account in order to express my opinions during the last campaign for the election of the French Republic President. Well, I am not naive and I know by experience (I have been myself a candidate for the house of Parliament) that a campaign may be (very) trash. However, what struck […]

Wire as you think

I was used to build my prototypes on strip-boards, burning my fingers, loosing my nerves and making many wiring mistakes because of the mirroring effect. And then came the illumination ! As I was visiting the R&D plant of my former division in Palo-Alto I observed engineers using breadboards to design yet pretty sophisticated devices. […]