Apple IIe repair (and piggybacking logic chips for diagnosi)

I've written up my recent third Apple II repair, this time an Apple IIe.
http://www.classic-computers.org.nz/blo ... -video.htm
One interesting aspect of this repair is that piggy-backing a logic chip helped confirm a faulty one. I'd only ever used this technique with RAM. I'm sure it only works if the chip has a particular type of fault, but it worked this time for me.
http://www.classic-computers.org.nz/blo ... -video.htm
One interesting aspect of this repair is that piggy-backing a logic chip helped confirm a faulty one. I'd only ever used this technique with RAM. I'm sure it only works if the chip has a particular type of fault, but it worked this time for me.