i tinker on stuff in my garage , lesson learned yesterday was to lock the F'n dog in his run when using a logic probe or an O-scope. i have hours into an atari AVG board with a wonkey DAC signal , found the issue and was moving to the next section and the dog decided it was ball time and nose nugged the board and the o-scope probe made a short on the DAC releasing magic smoke from 3 (that i saw) IC's.