Recent content by androda

I actually don't have a RaSCSI, and might not be able to help very much. PowerBooks don't provide termination power to the external SCSI bus, so the RaSCSI has to be powered by a USB cable in this scenario to my understanding. It's a little unclear why changing the power adapter for the...

F4 and F4Lite BlueSCSI use an active termination system which shouldn't cause cross-talk when used mid chain. Some models have resistor packs that are removed to disable termination, and others use bus switch chips to move the terminator resistors out of circuit. Removing the resistors packs...

A 9 volt external power supply is too high. The power supply needs to be 7.5 volts at a current limited 1.5 amps maximum. Any higher voltage or amperage is going to start cooking the power regulator mosfet because it has to burn off the extra power as heat. The Mac Portable uses a linear...

Sounds like more in depth work might be necessary on this poor machine. Portables really get eaten alive sometimes.

If you have a multimeter, check the voltages on either side of both diodes. This will tell us whether the terminator is getting enough voltage.

Sitting on grey screen with no other life signs sounds like a termination issue to me. Also given that this particular unit works on other machines. Is this one of Eric's V1 designs? If the termpower line in the SCSI cable is low, it will not provide enough voltage for termination to...

Yes, this project has been in progress for a little while now. The prototyping PCBs (with holes for resistors instead of SMD pads) were made last month, and finally found time to put them together last week. I went a little overboard and made a two-PCB system. There's the hybrid PCB with same...

It's definitely a better idea to replace capacitors as soon as possible. If there's capacitor fluid present on the board, running an electric current through the traces will cause the fluid to actively eat away the copper. Due to this literal electrolytic effect (they are called electrolytic...

Sure. These flex cable recreations are what I do with spare time, so they can take a little while to complete.

As I recall, the 180 is all tantalum on the motherboard, not sure about the display. The backlight control and inverter board almost certainly has an electrolytic.

Maybe. Flex cables are pretty expensive though, on the order of $20 per cable as the raw manufacturing cost (set of 5, plus shipping), so it would be good to have a few people that want one before doing a test run.

If trying the bodge wire doesn't work out, I'd be interested in the cable for duplication purposes. Display flex cables like these are starting to crack and die, so we need to be making new ones. I've had success with one cable so far, looking to do more over time.

Very much so, unfortunately. On the backlit portable, power manager chip is the primary point of failure. There are not really any replacement chips available, and no one has created a replacement yet. The backlit portable's power manager chip connects to the VIA in basically the same way the...

Here's hoping the screen capacitors have been replaced - they eventually go bad and then cause a solid black screen. I like the looks of the 1xx series powerbooks. Those and the Wallstreet G3 are my favorite.

To me this looks like a possible combination of error codes. The 00001FFA makes me think it could be related to the interrupt (NMI) lines, like this Reddit person mentions: Check IPL0, IPL1, and IPL2 on the mac portable schematic, check that they connect properly. If something's wrong there...