View Single Post
Old 23rd Apr 2021, 12:23 pm   #1736
Join Date: Apr 2018
Location: Newbury, Berkshire, UK.
Posts: 824
Default Re: Non-working Commodore PET 3016

I guess everyone has already worked this out, but the "jumpers" on the board allow the 2 cassette ports to be "switched". On the original PET interface #1 was on the lhs next to the transformer, and interface 2 was on the back. On later models interface #1 was on the back and the 2nd cassette was inside the case on the lhs. I imagine when laying out the board for the 2nd revision and on, they put in provision for jumpers so a "new" board could be put into an "old" PET with built-in cassette (for repair purrposes). As is often the case, the "standard" configurations are pre-wired with thin tracks since the majority of "new" boards would be going into "new" computers. If the main board needs replacing in a PET with built in cassette then the procedure presumably was to cut the tracks and fit actual jumpers.
Slothie is offline   Reply With Quote