Shure - take a 60 (or 50) Hz clock feed the signal and stop the time neded to show a minute (or 10 minutes to get fractions) - or take any other steping device and look at the stepping speed - This way you could even use an old Apple DISK ][ as a counting device - put it on track 30, hook up the signal and wait until it reaches track zero - you'll get an acustic feedback - now its just finger calculations. Servus H. -- Ich denke, also bin ich, also gut HRK