Arriving home at night and having to put the key in the dark to enter the house is something that has always bothered me. When we are at home and some are missing, we usually leave the light on but since there is not always someone at home, I have devised a system so that when it is dark and someone approaches the door, the light will come on.

To build it I used the following:

• A 5V relay module.
• A PIR sensor.
• A potentiometer of 100K.
• A 1N4007 diode.
• A pair of resistances of 5k6.
• A resistance of 47k.
• An electrolytic capacitor of 100uF.
• A pair of BC546 transistors.
• An LDR.
• An electrical installation box that I bought in Chinese.
• A recycled mobile charger to get the 5V to power the circuit.

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Since the first thing I've done with the display, the first part of the clock I made was its driver.

The display that I used has been a CL5642BH-33. It is a 4-digit display and 7 segments of common anode with double point in between, ideal to make a clock huh This display has a particularity compared to other 4-digit and is that the point for the digit 1 is disabled . Connecting the DP led to the COM1 what turns on is the point of the digit COM2, because the DP + digit COM2 what turns on are the two dots in between. (more…)

After having done the project of the digital clock in VHDL, I became very interested in the subject and thought, why not do it the old way? Using TTL and CMOS logic, of the integrated 7400 and 4000 families: decoders, Read more…

In the subject of digital electronic systems, as work, they asked me and my colleagues to make a watch in VHDL. VHDL is a hardware description programming language that is far from the conception of programming that is to program high-level languages ​​such as C / C ++, but for things like these, it ends up being intuitive. Even one of the programming modalities (Behavioral) makes them look alike.

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Since I started with the pedals, I told myself that unless it was strictly necessary and I could not replicate them as it may be the case of the digital processing pedals or those that would constructively cost more, I would do my pedals.

At the time I budgeted to be a Wah, and between boxes, special potentiometer and the inductor, the item was over € 60 and did not compensate me much. So they gave me the VOX V845, the modern VOX Wah, for my birthday.

The truth is that yes, the pedal sounded good, but I did not finish convincing. My pedal, being the "cheap" had no input buffer or TrueBypass so when putting the Wah in the line of pedals, "sucked tone". That is why it did not take a month to make the first mod: the TrueBypass. The great downside of this mod is that the 3PDT that I bought had the shorter shank than the SPDT carling that the original Wahs carry, so the Wah was somewhat hard, later, I removed the tires that damped a little and solved.

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