Once upon a time I purchased a working original Macintosh and Mac Plus for the Mac Museum. They came with a large device that was said to be a “modem” but didn’t have a phone jack on it. After being unable to figure out how to connect this odd device to a phone line, I put it away doubting that it was a modem. One day it dawned on me that it was actually a SCSI external hard drive that would fit right below a Mac Plus. I had a Mac Plus and decided to plug it in and try it. As soon as I flipped the power switch the Plus went into a boot seizure and repeatedly made clicking noises without actually starting up. And that’s how my Plus stopped working.
Luckily I came across another Mac Plus that booted to a Sad Mac and an error code. I looked up the error code, figured out that it was a ROM problem, and decided to do a ROM transplant. After ordering a 6″ Torx T15 screwdriver from Sears I had all of the tools that I needed to crack them open and do a transplant, assuming that the ROM chips were removable. I opened one up, slid out the motherboard (which is easy as they are designed to allow the user to upgrade the memory), and found out that the chips are indeed removable. After some gentle prying I had the two chips out (hi ROM and lo ROM in case you care). I put them into the other Plus, plugged it in, and amazingly, it worked! YAY!
I’ve never actually done any sort of a chip transplant on any of my Macs so it was pretty cool to crack them open and find out that it worked. In addition I also had a chance to take a look at the signatures of the Mac team (including Steve Jobs) that were inside the case. Pretty cool. So that Mac Museum now has a working Mac Plus again.