I assumed that the Commodore 1581 was failing because of a bad WD1772 IC (as documented in Part I). So I ordered a WD1772 replacement + the IC socket, I developed some basic desoldering skills, watched some desoldering videos, and also got a cheap desoldering iron from Radio Shack:
So, I removed the board from the Commodore 1581 and started to desolder the IC. To my surprise the $11-buck desolder iron worked pretty well. I was able to remove all the solder from the the pins in a few minutes. The desolder iron just takes some time to reach the needed temperature, but besides that, it seems to be a great tool for occasional desoldering tasks (a hobbyist desoldering iron cost more than $250)
I removed the old WD1772 IC, solder an IC socket, installed the new WD1772 IC, assembled everything together again, plugged the Commodore 1581 into the Commodore 64, did a LOAD”$”,8 and…
and got again the FILE NOT FOUND ERROR. Sigh.😞
Time to double check everything:
- Did I solder the IC socket correctly? Did I clean the pin holes correctly?
- Is there any trace broken?
- What happens if I remove the WD1772? Will it behave the same way?
- And if the problem is not related to the WD1772, what’s the origin of this problem?
Unfortunately I didn’t have time to keep testing.