BTW For finding clocks, a spectrum analyzer and a small H field probe is much better than a scope. Less risk of disturbing the circuit operation and it's easy to locate the clock lines even if they are buried.
I've used a simple loop of 26 AWG wire on a scope probe tip with the SA app for the Instek MDO for this. Strictly speaking it's both E&H, but H dominates. I also made a heatshrink condom to insulate a scope probe tip for use as an E field sensor. The 1/4" antenna localizes signals extremely well. Both ideas came from an old article by Bob Pease.
Don't use your probe tip as a form for winding the loops to fit the probe tip. Measure them and use drill bits for forms.
