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I just finished recapping an LC III power supply unit (PSU). The Machine was not working because of the power supply unit (PSU). After recapping, measurement of all the power rails showed that not all of them are stable. Keep moving around, but not at the correct voltage. Any pointers on what to...

Working on a Macintosh IIsi for a client. The logic board and power supply unit (PSU) have been recapped. The unit starts up and boots perfectly, but after a couple of minutes, a white screen appears with some bars. The machine has to be powered down manually. I check my work; everything checks...

Working on a Macintosh IIsi for a client. The logic board and power supply unit (PSU) have been recapped. The unit starts up and boots perfectly, but after a couple of minutes, a white screen appears with some bars. The machine has to be powered down manually. I check my work; everything checks...

Good news. I got it working! The issue was the right sensor. I decided to desolder and swap the left and right optical sensors to test. The Right sensor, one of the legs was completely gone (rusted). I use an exacto knife, to remove part of the plastic to expose a good part of the little leg...

Hey team, anyone? Could someone please tell me how to test the optical sensor with a multimeter? Again, the drive works great, the only issue after ejecting a disk, keeps trying to eject, it thinks that a floppy is in the drive. If I insert a new disk, everything works great! I attached an...

I clean the 2 photo sensors. I thin the one on the right side is the one that detects if a floppy is inserted right? Maybe is bad. Does anyone have a 400K drive for parts?

After Fixing a Mac 128K Logicboard and Analog board, I focus on the 400K Floppy drive. After Recap, lubrication and assembly. I was able to boot from it, initialize disks, copy files, and eject perfectly but I have a question regarding the behavior at power on without a Floppy on the drive. If...

I am happy to inform you that the unit is Back online! A little surprise that no one replied to my original post...

I found an issue... The line going from CPU on pin 59 (D10) fail continuity to G7 pin 2. Will test some time tomorrow,

Verify One more time, forgot to solder one pin...image is better but same issue. Move the G7 Memory to another location, the error dont change. Regarding the Vertical lines. I think still an issue on the Analog board, any directions?

I have desoldered and tested the following Logic connected to the memory, all pass ok. 74LS257 (2) 74LS161 (2) 74LS166 (2) 74LS257 (2)

I got a Mac 128K at VCF a couple of weeks ago. The unit didn't do anything. First, recaped the analog board and the main logic board but still nothing. After a couple of tests, discovered the flyback transformer was dead. Replace it from a SE/30 Analog board and the unit power on, give me a...

Yes! the machine will work, aparently the replacement RTC base on https://hackaday.com/2023/01/13/swap-the-clock-chip-on-the-mac-se-30-with-an-attiny85/ has some timing issues. I put a original back, and everything work.

IT was the RTC IC - OMG! So the SCSI issue is resolved. Now to the Horizontal Bar logic board. No sound...Socket are new, for the ROM and SIMM. Swap ROM with another working system, same behavior.

Update, the board with SCSI issue, It can see the drive or BlueSCSI v2 volume, mount it, formated, partition it, install os but it will not boot from the HD or BlueSCSI. Now if I turn off and back on qucik, the machine boot from HD or blueSCSI. Regarding the Horizontal bar, I dont get any sound.

Update: New SCSI IC, no luck. Out of options....

On the First Logicboard - SCSI issue. I remove the socket for the SWIN and SCSI IC. No change. I order new SCSI IC from Mouser. Will update Thursday!. The Second Logic board. No clue yet!

All IC I took my time and clean them, use a brass wire brush to remove any rust. Plus use a multimeter with a needle probe to verify and trance every connection on the ISCSI, SWIN and Glue.

Analog board is ok, try with other SE/30, work fine! Already verify all the soldering point and check with multimeter. Board was clean using a Sonic Cleaner and 99% EPA bath after it! The Apple HD was remove 3 days ago from a working SE/30 upgraded to a BlueSCSI v2. Try BlueSCSI v2 with...

The logic board in the Left - with the SCSI issue The logic board in the right - with the horizontal bar issue