Review on Velleman MK101 VP Flashing Sweetheart Size by Edgar Clark

I love collecting these little hobby kits. Velleman makes some pretty good ones and I've built about a dozen of them. They all worked as advertised. One thing I don't like is things blinking and blinking at a high rate. I find it annoying. This heart is one of them. So I changed it. I've been in electronics for about 55 years and I'm not afraid to modify things. This kit flashes approximately twice per second when shipped from the factory. That's about a normal pulse, but too fast for me. The flashing frequency is determined by resistors R8 and R9. R8 is 33k and controls the time on the inner heart. R9 is 100,000 and governs the outer heart. I changed both to 270k which caused both hearts to light up for the same amount of time. They also slowed the rate down to about 2.5 seconds for each heart. I find it much more comforting, as does my wife, for whom it was a Valentine's Day gift. She loves it. It doesn't mimic a real heartbeat like the original resistor values do, but we're both okay with that. I also added a switch to the 9V line from the battery so I don't have to pull the battery out to close it. it's from. For machining I used JB Weld. Most Velleman kits don't have a switch, but for most it doesn't matter. A small problem was that most of the solder pads are small and very close together. You will need a very small tip on the solder pin to make the process easier. My soldering pin has a 1/8" tip, which is too big for this kit, but having been making something like this for decades, I've had no problems. Be careful with a solder bridge between two pads, especially with LEDs. .Otherwise have fun.