Turn your PC Into a Frequency Meter
By Dave Bojanowski
I am an Electrical Engineer who wishes to make his own set of golf clubs. I have read much of Dave Tutelmans literature on the web and have obtained catalogues from the major component suppliers. I am in the process of characterizing my swing speed and the current clubs that I am using. My hope is to understand something about my golf game before I order club heads and shafts. In the process I thought about a way to use my PC to measure the resonant frequency of my golf club at a cheap price. I am hoping that this can be shared with other club makers. The method uses the WAVE STUDIO (tm) software that came with my sound card to record the vibrations of the club using a PC microphone. I set up a work bench with a clamping mechanism to hold the club, the stiffer the work bench the more accurate. Next I constructed a simple noise device by nailing a thin plastic strip 3 inches long to a short scrap of 2by4 wood. I place the block of wood with the plactic strip about 1/2 inch from the shaft of the club. Then I place the microphone about 1 inch from the plastic strip. As the club is "plucked" it will vibtrate and each time it contacts the plastic strip a noise will be picked up by the microphone. By recording this noise with the WAVE STUDIO (TM) software I can measure the time in milliseconds for 10 cycles of the club. Then I use mathematics to calculate the CPM (CPM=60sec/min*10000/time in ms).
Please feel free to pass this along. It is a lot cheaper than a $600 frequency meter assuming that you have a computer and if you want statistical information Excel (TM) can be used to figure out average and confidence level.
Dave Bojanowski