jmacz journey

[jmacz]

Hmm interesting... I had a 1.44MB floppy drive that I hadn't tested yet. I fixed all the usual eject gear related stuff and then attempted to test it. The eject mechanism seemed fine but there were other issues, namely:

• Drive couldn't tell the difference between a 800K and a 1.4MB disk.
• Drive couldn't tell the difference between a locked and unlocked disk (always thought it was locked).

I figured I should check the little switches but I didn't think two switches would be bad at once and thought it might be something else.

Moved the floppy drive into another computer and had the same issues. Moved a working floppy into the first computer, works fine. So definitely the floppy drive. So I went ahead to check the switches. I compared the switch behavior with a known working floppy and found:

• Two pins on the disk detect switch were shorted internal to the switch. And it wasn't the pins that were supposed to have continuity when a disk is inserted. Did not match the working floppy (same model #).
• The lock/unlock switch doesn't close when the trigger is depressed with a floppy. You have to really push it in to get it to work.
• The 800k/1.44MB switch also doesn't close when the trigger is depressed with a floppy. Again, you have to really push it in to get it work.

I checked the chassis for bends, etc to see if that might be causing the switch problems but no. It's to spec. I also confirmed the short on the detect switch after pulling the switch off the floppy board.

I have a fried floppy drive that I have been using as a parts donor. I grabbed the 3 switches off of it and transplanted them to this floppy drive. The drive works great now and tested fine on all of the above as well as read/write/eject.

Really weird that all 3 switches were bad.

 

[jmacz]

Uh oh... couldn't resist. Quadra 800 on the way, supposedly working but we'll see.

I believe the Quadra 800, like my Quadra 700, already had tantalum caps so I think the only thing I have to worry about is the battery.

 

[bigmessowires]

The Quadra 800 is a nice looking machine! I had one briefly perhaps 10 years ago, but it was "too big" and I sold it to another eager buyer here.

 

[jmacz]

The Quadra 800 is a nice looking machine! I had one briefly perhaps 10 years ago, but it was "too big" and I sold it to another eager buyer here.

Yeah, I'm a little worried it might be too big. Not even sure why I got it since I have a 700 already. Impulse buy.

I was down to just the Macs I never want to sell (listed in my signature). Will need to decide on this one once I get it.

 

[lobust]

Yeah, I'm a little worried it might be too big. Not even sure why I got it since I have a 700 already. Impulse buy.

I was down to just the Macs I never want to sell (listed in my signature). Will need to decide on this one once I get it.

The 650/800 is noticeably quicker than the 700 in use. I cheated and put a spare 800 logic board in my 700 case.

 

[jmacz]

I received the Quadra 800 today. It had the original battery inside and it was starting to leak but luckily it was contained to the battery holder. It did not spread beyond there. Took that out immediately. The power supply seems to be ok but have not booted with the power supply yet. Instead, I powered up the motherboard using a bench power supply and everything seems to work. The board looks clean (minus the battery holder). The case is in relatively good shape, very few cracks in the plastic. The programmers buttons are intact. The only major broken item is the CD-ROM bezel which has broken clips and won't stay on. Have not tested the CD-ROM drive yet. Will have to do some more testing over time.

 

[olePigeon]

@jmacz If all three switches failed, I would guess high humidity or liquid damage causing corrosion or oxidation on the internals.

 

[bigmessowires]

That's a nice find with the Q800, it sounds like it's in comparatively good condition. I expect to see your new 3D-printable CD-ROM bezel model by end of the weekend.

 

[jmacz]

That's a nice find with the Q800, it sounds like it's in comparatively good condition. I expect to see your new 3D-printable CD-ROM bezel model by end of the weekend.

LOL

 

[lobust]

I received the Quadra 800 today. It had the original battery inside and it was starting to leak but luckily it was contained to the battery holder. It did not spread beyond there. Took that out immediately. The power supply seems to be ok but have not booted with the power supply yet. Instead, I powered up the motherboard using a bench power supply and everything seems to work. The board looks clean (minus the battery holder). The case is in relatively good shape, very few cracks in the plastic. The programmers buttons are intact. The only major broken item is the CD-ROM bezel which has broken clips and won't stay on. Have not tested the CD-ROM drive yet. Will have to do some more testing over time.

The cdrom drive in my 800 needed recapped very badly. I didn't realise it at first because it worked fine with actual cd roms, it was only when I discovered terrible audio quality with audio cd's that it came to light. A good number of the pads under the caps were basically gone and required extending traces back to the new cap, however the damage was very local to each cap and hadn't hurt anything else around them.

 

[ObeyDaleks]

Spent some time today replacing the ATX PSU inside my converted IIci PSU with an SFX PSU instead. Reason was the older ATX PSU that I previously used has group regulation of the power rails which was causing an issue on loaded machines. I swapped it for a newer SFX size PSU that has DC-DC support allowing for more tighter regulation of the 5V line.

Here's the new SFX PSU sitting inside the IIci PSU enclosure.

View attachment 65109

The holes for the standoffs obviously didn't line up with the old PSU and so I had to drill two new holes into the enclosure. The third hole was reusable. I went with the same Noctua fan I had previously. This time around I tied all the 5V lines and all the ground lines together and used larger gauge wires for it. Looks kinda cool.

View attachment 65110

You can see the DC-DC converters in the lower right. Also the little board mounted to the side wall is the inverter circuit. Still using the NPN transistor based inverter for the startup signal.

View attachment 65113

All buttoned up and ready for my IIci. Or I can use it on my Quadra 700 as well.

I have three PSUs of this size now. One is this one above. The second is still using the group regulated power supply and I will use that for my lightly loaded IIci. The third is a stock PSU (Delta brand) which is still ok and I don't see any leaking caps so hopefully it lasts a while.

Very cool. I’ve done this type of conversion with a few PSUs, including the soft power circuit and a fan replacement. It’s a lot of work, especially if you want the PSU and connectors to look stock on the outside. Yours looks very clean, well done!

 

[jmacz]

The cdrom drive in my 800 needed recapped very badly. I didn't realise it at first because it worked fine with actual cd roms, it was only when I discovered terrible audio quality with audio cd's that it came to light. A good number of the pads under the caps were basically gone and required extending traces back to the new cap, however the damage was very local to each cap and hadn't hurt anything else around them.

Doesn’t surprise me. I opened up a AppleCD SC Plus a few weeks back and found the caps leaking badly. Thanks for the tip, will check it out.

 

[jmacz]

Very cool. I’ve done this type of conversion with a few PSUs, including the soft power circuit and a fan replacement. It’s a lot of work, especially if you want the PSU and connectors to look stock on the outside. Yours looks very clean, well done!

Thanks!

 

[jmacz]

That's a nice find with the Q800, it sounds like it's in comparatively good condition. I expect to see your new 3D-printable CD-ROM bezel model by end of the weekend.

Still a work in progress. Going to require some trial and error to get the curve right. I think it's close right now but won't know until I print one out and see. But still not sure whether I'm going to keep that CD-ROM drive there or replace it with an MO. I guess the beauty of this is that now I can cut out whatever slot I want.

 

[lobust]

Still a work in progress. Going to require some trial and error to get the curve right. I think it's close right now but won't know until I print one out and see. But still not sure whether I'm going to keep that CD-ROM drive there or replace it with an MO. I guess the beauty of this is that now I can cut out whatever slot I want.

View attachment 65438

View attachment 65439

I feel like I have seen an original drawing for this. The Quadra 650/800 developers note maybe?

Edit: nvm it doesn't show the curvature. It would take me a couple of minutes to scan one on my cmm, but I still don't have it setup in the new workshop

 

[jmacz]

Fitted a magneto optical drive into my IIfx this weekend (documented here).

 

[jmacz]

Made new slot covers for my Macintosh IIfx, Macintosh IIci/Quadra 700, and Macintosh SE to allow the use of a micro SD card extender so I can get easy access to my micro SD cards in the internal ZuluSCSIs.







And here's how it looks (note that the picture of the Quadra is showing another prototype for a full SD card sized one).







I have attached the STL files for the models I used to this post. BUT, it's obviously designed to fit a specific micro SD card extender. This is the one I bought off Amazon:

https://www.amazon.com/dp/B07YYSP5F5

The extender can be double sided taped onto the mounting platform on the slot covers.

 

[jmacz]

For the front drive bay covers, another option is to just replace the broken hinges and clips. Made some parts that seem to work.







Models attached.

 

[jmacz]

Picked up a Macintosh Plus with some additional peripherals from @MicroCoreLabs today (nice meeting you!). One of the last two remaining 68K Macs on my list from my childhood. Only one remaining is the 512K which I am in discussions about.



The Plus works and is in good condition, just needs some clean up. Should be fun to work on after my current other projects.

 

[jmacz]

Looked what arrived in the mail today... going to start on a Design68 ANSI keyboard (@demik).



If the first one goes ok, I think I'm only going to make one more... so I'll have 4 boards remaining if anyone's interested.