Paintball marker. 2013-12-09

Since it's not possible to do martial arts for me any more due to different knee injuries i needed to find a new hobby. It became paintball.I own a marker which is of semi pro quality. Often when i play i want to know if  i have few bullits left.

So i built a small levelsensor consisting of a LDO TPS77025 from TI which has 2.5V output, and a Pic12F675 (of course). The circuit is powered by a CR2032 battery. The way of detecting few balls is easy. I use a phototransistor FPT100, that detects light. If there are balls the phototransistor is covered and no light reaches the lens.

The unusual for this project is that it's SMD and the PIC is powered only by 2.5V which is within the specification for the PIC. Also the LDO is a low power variant.A great solution i believe!

There are three  "blink modes" to understand the function.

1- LED short blink every tenth second: normal mode, more than appx 30 bullits in mag2- LED short blink 2Hz: warning mode, less then 30 bullits in mag3- LED on: low battery

Flashing the PIC circuit onboard the small PCB.

The complete marker with mag and level sensor mounted.

Using the logger Wellerman PCS100 to determine battery life time.This time is only measured for normal mode as mentioned above.

The goal was to have at least of 20h battery life time. After 91h the logger crashed and logging stopped. at this time battery voltage was around 2,74V and i consider the battery drained at 2.54V. With this i believe the total lifetime to be around 110-130h. Well above the prediction!

Remote controlled hatch opener. 2013-04-07

I have a hatch up to the attic that i wanted to design a remote controlled opener for. The project below is the second and now fully working version. The first version hade major issues with false triggering when i turned on different lamps in the house and not only triggering on the remote controll.

Click below  to see how it works!!!