Note to self: don’t use expensive test equipment with unverified circuit

Expensive test equipment, especially those that have lax input protection, must be the last to be used with unverified circuits and prototype boards. I know it is obvious to the experienced, but nevertheless important to remember. Test the signals with a multimeter or oscilloscope, and ascertain they don’t exceed the input specs of the test equipment. Add that to your checklist if you have a hard time remembering it.