I've been working on an electronic clock timing machine. Right now It just provides basic functions. It shows the beat time of a clock and the beat error. It also has a software moving average filter to give more stable readings. I also have added an adjustable retrigger or blanking delay. When I look at the specs of commercial machines like the Timegrapher or Microset I see that they have many functions. I'm certainly not going to try and duplicate all of the functions of these machines. I'd be writing code forever. Also, I'm primarily interested in clocks so I won't be needing any functions used only for watches. Do you have a clock timer? What are the features that you find most useful? I'm thinking of adding a beats per hour readout. Right now I'm controlling my timer with a serial terminal connected through a wireless bluetooth interface. It outputs data in CSV (Comma separated values) format. You use keyboard commands to change options like turning logging on or off and adjusting the retrigger delay. I'll eventually add some pushbuttons so that it can be run without being connected to a PC. So far I've found that logging the data to a file and then graphing the data is the most useful thing. I'm using a free program called KST for this. Would anyone be interested in building one of these? You'll need some electronics skills. If there is enough interest I'll do a schematic and other information needed to build it. If you have the skills to build it yourself this is a fairly inexpensive project. I only have about $30 worth of parts in it. Most of the cost is in the display and the bluetooth module. [video=youtube_share;tZRPY4SqQ0Q]http://youtu.be/tZRPY4SqQ0Q[/video] The first three pictures are the timer. The next two are an optical sensor and piezoelectric vibration sensor. The next two are graphs from a self winding clock. The first is raw data and the second is with a moving average filter applied. The glitch each hour is disturbance caused by the clock winding motor. The last picture is the serial terminal screen.