Recent content by point5

Another Update... Finally got my hands on a genuine Kanga display (and parts for the rest of a Kanga - some working some not) and guess what, the display unit is electrically identical to the 3400 display. So shame on me for making that assumption about a wiring difference. Turns out the reason...

So the squealing sound has returned. Looks like if I want to use the 3400 display, the bodge is not enough. I will need to cut the trace on pin 34. And possibly pin 32 as well. I will have to experiment further. Of course the best solution would be to get a kanga display or at the very least the...

A few months back I purchased what I thought was a 7100 from Ebay. What I got was a performa 600 with a 7100 face. The seller made it right but I do recall he had a performa 600 up for auction at the same time. I suspect someone got a 7100 with a performa 600 face. If you are that someone, and...

Well that was a bad idea. No harm done, but I got some squealing sounds from the speakers when I shutdown. Undoing the bodge from pin 32 to 34, and replacing it with a bodge from pin 18 to 32 seems to be the right way to do it. No squealing and no more issues with the backlight dropping out...

For anyone following along, I have gotten a backlight on the 3400 display from kanga board -of a sort. It turns out that there are in fact slight differences in the display connector on the kanga logic board and the 3400. Specifically, on the kanga, pin 18 outputs 2.5 volts and pin 32 measures...

A quick update. After more cleanup and some more reflowing, I finally have the display working dependably, except for the backlight. To be clear, the display works fine on a 3400, but no backlight when connected to this kanga logic board. I am hoping someone here has some info on the internal...

On the bench today is a powerbook G3 kanga motherboard, with some odd display problems. First let me state that the display I am using to test with is from a working powerbook 3400c and works just fine when connected to the 3400. When the kanga is booted up, I can always get good video from the...

So today I did the resistor swap that boosts the Performa 476 (LC 475, Quadra 605, etc) from 25Mhz to 33Mhz. And for fun I also swapped the 040 chip out with a couple others I have to see the difference. I tried with the stock 040 25 LC. an 040 33 LC, and a full 040 40. Using Mac Bench prior to...

One last unrelated item on this, one of the clips that hold the ram in place was broken and the last chip in bank B could not be kept in place. I created and 3D printed a clip to hold the chip in place. If you might find it useful, it is freely available on thingaverse...

So, after some quick googling , I went down a rabbit hole and replaced the HC132 at UD13. But of course that was not it. Next I took voltage readings at pin 3 of UD13 while running before and after pushing the power button, it flopped fine. So I traced the +5v from there through all the diodes...

Update #3 for those following along... Using the schematics provided by Kai (many thanks), I was able to tone out all of the chips in the area around the power button (ADB, swim, via, scsi, etc.) After confirming connectivity, I went on a hunt for more information about the boot up process and...

Thanks Kai, I was beginning to think the apple version was lost to the ages! heh. Hopefully I can spot something new with this version. And incase anyone in the future might find it helpful at all, I will add the pdf I have been using here as well.

Also just wanted to say thanks to everyone for any help given. Sincerely appreciated.

I have tried several things. 4 - 1mb sticks of 70ns in bank A - nothing in bank B, 4 - 4mb sticks of 80ns in bank A nothing in bank B, and 4 - 1mb sticks of 70 in Bank A with 4 - 4mb sticks 80ns in bank B. All scenarios give the same result. Both sets of simms work fine in a performa 600 as a...

I am using the Bomarc schematics. I found a pdf online and re-stiched the half pages back together in photoshop so I can look at them as flattened full pages.