Quoted from Validpowerdetect:Logic probes are ok, but an o'scope will show you so much more. They are not that hard to use, plenty of online tutorials, and some great bargins can be had on used units on ebay.
One easy way to use one, is to go through a known good board, taking pics of pertinent signals on the display, then compare to the board giving you trouble.
Also, o'scopes can be a valuable tool troubleshooting power supply boards. DC,AC, and ripple can allbe easily observed.
I hope to agree with you! I bought a handheld scope a while back and am looking forward to getting acquainted with it on this World Cup I'm reconditioning. It will be my first use of a scope since tech school back in '84-'85. Hopefully a rewarding learning experience!