Are there factory bodges on MZ-80K PCB?
Posted: Wed May 18, 2022 11:01 am
Hi all,
I'm in the process of restoring a previously very heavily modded MZ-80K. Videos here: https://www.youtube.com/watch?v=NiAL5LC ... eByteAttic.
I'm now troubleshooting the machine, and noticed that there is nothing connected to the shift-clock input of the shift register responsible for the display bit stream (the 74LS165). The schematics call for the 8MHz clock to be there, but there is no trace on the board leading the clock to that pin. My current hypothesis is that there was a factory bodge there, which I removed along with all the other bodges made by the previous owner. Does any of you know whether there were factory bodges in the original MZ-80K PCBs, European version?
I've noticed other inconsistencies between the schematics in the service manual and the particular PCB I own. Is it known whether the schematics are inaccurate?
Thanks for any feedback!
I'm in the process of restoring a previously very heavily modded MZ-80K. Videos here: https://www.youtube.com/watch?v=NiAL5LC ... eByteAttic.
I'm now troubleshooting the machine, and noticed that there is nothing connected to the shift-clock input of the shift register responsible for the display bit stream (the 74LS165). The schematics call for the 8MHz clock to be there, but there is no trace on the board leading the clock to that pin. My current hypothesis is that there was a factory bodge there, which I removed along with all the other bodges made by the previous owner. Does any of you know whether there were factory bodges in the original MZ-80K PCBs, European version?
I've noticed other inconsistencies between the schematics in the service manual and the particular PCB I own. Is it known whether the schematics are inaccurate?
Thanks for any feedback!