djfitzgerald
Experienced Member
I started work on a PCjr at the March VCF East repair workshop, and have been running into some issues with the floppy drive. I have been having intermittent problems with it playing a game, and suspect a possible drive issue. I'll presently describe what I did and what I observed, and would be interested in hearing anybody's thoughts on what could be the root cause of this problem.
At the workshop, the floppy drive had been all bound up and Sark (who was working on two other bound PCjr Qumetrak 142 drives for the VCFED) worked on lubricating it until it could read again. When I got home, I started playing with the drive myself. I made a King's Quest I floppy from an image on Archive.org, and tried to load it in the drive. It would work only intermittently. I tried making the disk image with three different floppies and got the following results:
At the workshop, the floppy drive had been all bound up and Sark (who was working on two other bound PCjr Qumetrak 142 drives for the VCFED) worked on lubricating it until it could read again. When I got home, I started playing with the drive myself. I made a King's Quest I floppy from an image on Archive.org, and tried to load it in the drive. It would work only intermittently. I tried making the disk image with three different floppies and got the following results:
- Floppy One - This was a non-name floppy that may have originally come from boxed software. On the second or so time I tried booting it, I was able to get to the actual game. However, subsequent tests would only get as far as the program splash screen before stopping. The text input prompt (below the splash screen) would show a '±' character in blue after the white prompt '>', and if I hit the ENTER key, the disk drive would read but that prompt and symbol would come back and I couldn't make any more progress. When I finally gave up and reformatted the disk on a Windows 95 machine, it reported a number of bad sectors, which was probably the cause.
- Floppy Two - This was an older IBM-branded DD floppy (blue label with white text). I could not get the PCjr to recognize it as a bootable disk. One time after starting with Floppy One and getting stuck at the prompt, I swapped it for Floppy Two and upon hitting ENTER the game would load. When I took the disk drive out of the PCjr, I saw that the hub would get stuck with this particular floppy in the drive: it would start spinning, but then get physically stuck a bunch. I tried to disassemble the drive and remove the hub so that I could lubricate its' shaft, but I couldn't get the hub off the shaft. Instead, I sprayed WD-40 silicon lubricant underneath the spindle pully (the part attached to the bottom of the hub and its' shaft) in the direction of the hub's shaft. This seemed to fix the intermittent sticking problems, but the PCjr still couldn't read the floppy as bootable. When I reformatted the disk on my Windows 95 machine, it reported no bad sectors.
- Floppy Three - This was a newer IBM-branded DD floppy (yellow label with black text). The PCjr recognized the floppy as bootable and went into the game. The first time I played with it, I got past the splash screen, and to the first game screen. I walked over the bridge to the second game screen, opened the door, went down the hallway (third game screen), made a left turn (fourth game screen), and entered the throne room (fifth game screen). I talked to the king and got his monologue. Thinking that everything was fixed, I put the PCjr back together and invited my roomate down to play the game. She got as far as the third game screen, but when she left the screen to make the left turn, the computer started to read the disk and the fourth game screen would never load. We tried this after a number of restarts and got the same result each time. When I reformatted the disk on my Windows 95 machine, it reported no bad sectors.