In the wintertime the evenings get dark and therefore plunging in to the dark lake is not as pleasant as it is in the summer. Led lights to the rescue!
Above is a photo of the lights in a pool, or actually a hole in the ice in a lake.
Submergible led lights can be made with a car battery, a couple of 1 watt leds, a constant current driver, a piece of clear 1 inch diameter PVC hose and two small pieces of e.g. aluminum profile for led heatsinks. The leds Continue reading Submergible 12V swimming pool lights
You will need some source of electrons for every project. It did not take long before I started to think about other power sources but the obvious batteries. My first power supply was a simple LM317 based one with a potentiometer to vary the output voltage. The one important feature that was missing was current limiting. I saw an old Elektor magazine article (Elektor 7-8/2008 p. 106) about a mini bench supply that seemed like just what I needed.
The schematic needed a little tweaking Continue reading Variable voltage bench supply with current limiting