Electronics

1°) I have connected my power counter to my gateway's serial port (RS232, 7E1) and I retrieve its data stream. Given that I pay for electricity once per month, I got 1 file per year. This system allows me to track my power consumption. By this way, I get daily/mensually/yearly rating. At the end, I have some nice graphs. Picture.

As of 2011, this project has been restarted with a different approach. The project is hosted by EMG-BOX now.

2°) A small (30x60 mm) digital RPM meter for my Peugeot 205 Diesel (or any other vehicle). Designed with Eagle and AVR Studio:
- AVR programmer (schematics & pcb & bom): here
- RPM meter (schematics & pcb & bom): here
- firmware for RPM meter (source & binary): here
The RPM meter has been published in the Elektor Magazine (French edition, juillet/aout 2008).
Note: programmer schematic is based on Mike Perks' page but programmer firmware is taken from Klaus Leidinger's page for compatibility with AVR Studio 4.

3°) I have some other projects in the while: power supply, electronic load and an UPS. Coming soon...

4°) As of August the 13th 2009, I added atomic time synchronization (DCF-77) to my server. Schematic of such a device can be found on the Jurgen Beisert's homepage
But, this simplistic receiver may not work in poor reception conditions. This is the reason why I develop an active antenna. This active antenna uses a better ferrite rod (higher quality factor ~70) than provided with the module. The rod is tuned on 77.5 kHz frequency station and 2 transistors are used to amplify low level signal.
This antenna can be located anywhere thanks to a differential transceiver connected to 2-pairs RJ45 cable. A second module is used to plug RJ45 cable and set levels to RS-232 standard.
You can look at pictures here and here.

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