Got a couple of original Rygar PCBs to fix (plus a boot that's probably just ram issues).
The first one has changing garbage on the screen,it looks like it's trying to boot but is constantly watchdogging.
While trying to fix that I found that if the ram from 7L is missing on the CPU board then I got a blank screen.
This was interesting as the other original was showing a blank screen so I swapped the ram out and got what looked like the game running but only showing a single colour.
No idea what caused that to happen as I never got that again but using my video probe I was able to discern that even though the screen was blank the game was running. I had not sorted out sound or control on the adapter yet so there was no chance of me hearing any sound FX.
Using my video probe I worked back and found video information was making to the ram at 7A,7B and 7C but there was still no picture and slicing theLS174s at 8A and 8B showed them to be fine.
It took a while of working back to find a missing COLOR RAM signal that goes to pin 2 of an LS32 at 5B. That is generated by pin 10 of an LS139 at 5R. Checking that on my scope showed a signal and when I ran a jumper between the two pins I got the full graphics.
So there's a damaged trace somewhere. Hunting for that I found it was somewhere under a socket that had been fitted by a previous owner to replace what I assumed was a bad LS258 at 2P that handles player one inputs. I decided to remove the socket since I was curious what the damage was. I thought it would just be a nick to the track caused by accident during the socket being fitted but what I found was this:
This is what looks like deliberate cutting of tracks. As well as the COLOR RAM track being cut a lot of the connections for player one controls were cut as well. No idea why this was done and the other original Rygar has nothing like this,the LS258 is still the factory one.
A bit of work and a microscope later:
I managed to fix the tracks in a way that would be hidden by the socket when I replaced it. With this done and control and sound sorted on the adapter it appears that this PCB is now fixed.
Unfortunately with the other original I was investigating the possibility of the T1 hybrid causing the board not to boot and I had an accident:
Damn thing broke off. I'm now trying to repair it. I've fitted a socket to the PCB and used a dremel to expose the connections on the edge of the custom to try and solder legs onto it so I can try it in the socket.
The thing is that the board appears to be showing the same activity with this custom missing and since part of it's function is controlling the main CPU roms/ram it could be the issue.
It could be that this custom has failed but fortunately there's a replacement so if the board still watchdogs after this repair I'll try a modern Caius replica.
The first one has changing garbage on the screen,it looks like it's trying to boot but is constantly watchdogging.
While trying to fix that I found that if the ram from 7L is missing on the CPU board then I got a blank screen.
This was interesting as the other original was showing a blank screen so I swapped the ram out and got what looked like the game running but only showing a single colour.
No idea what caused that to happen as I never got that again but using my video probe I was able to discern that even though the screen was blank the game was running. I had not sorted out sound or control on the adapter yet so there was no chance of me hearing any sound FX.
Using my video probe I worked back and found video information was making to the ram at 7A,7B and 7C but there was still no picture and slicing theLS174s at 8A and 8B showed them to be fine.
It took a while of working back to find a missing COLOR RAM signal that goes to pin 2 of an LS32 at 5B. That is generated by pin 10 of an LS139 at 5R. Checking that on my scope showed a signal and when I ran a jumper between the two pins I got the full graphics.
So there's a damaged trace somewhere. Hunting for that I found it was somewhere under a socket that had been fitted by a previous owner to replace what I assumed was a bad LS258 at 2P that handles player one inputs. I decided to remove the socket since I was curious what the damage was. I thought it would just be a nick to the track caused by accident during the socket being fitted but what I found was this:
This is what looks like deliberate cutting of tracks. As well as the COLOR RAM track being cut a lot of the connections for player one controls were cut as well. No idea why this was done and the other original Rygar has nothing like this,the LS258 is still the factory one.
A bit of work and a microscope later:
I managed to fix the tracks in a way that would be hidden by the socket when I replaced it. With this done and control and sound sorted on the adapter it appears that this PCB is now fixed.
Unfortunately with the other original I was investigating the possibility of the T1 hybrid causing the board not to boot and I had an accident:
Damn thing broke off. I'm now trying to repair it. I've fitted a socket to the PCB and used a dremel to expose the connections on the edge of the custom to try and solder legs onto it so I can try it in the socket.
The thing is that the board appears to be showing the same activity with this custom missing and since part of it's function is controlling the main CPU roms/ram it could be the issue.
It could be that this custom has failed but fortunately there's a replacement so if the board still watchdogs after this repair I'll try a modern Caius replica.