I am familiar with the various DIY lift reserve/angle of attack systems, but does anyone know of a good design for a DIY blade-type stall warning sensor? Aircraft Spruce wants $300 for this one, which seems a bit silly, and $90 for this one, which is better. Still, it ought not to be too hard to gin something up with a little sheet metal, some hardware and a $2 micro switch. The idea would be to connect it to a bright LED, a test button, maybe a buzzer or audio feed and a 9v battery to have a completely independent system. Something that could be easily adjusted after installation would be a plus. Any ideas?