Recent content by tigerstorm

Yep. You listed most of the reasons I choose to restore a IIci. No desire to mess with a CRT or claustrophobic case like the SE/30. And, the II series is kind of the first mac line to be easily expandable and, to me, marks a clear major step in computer (or at least Apple) evolution. It's...

Yes! Last night I was thinking over the circuit and looking at the bus schematic around UH1, TM0 and TM1. What I didn't realize is that TM signals were being driven by the card, but not by the NUCHIP30 bus controller. This morning, ai rechecked connectivity on UH1 and found that TM0 and TM1 were...

I have CLK on CH1 (yellow), RESET on CH2 (magenta), START on CH3 (blue), and ACK on CH4 (green). RESET is high normally and pulses low when system resets-- that seems right. CLK is 10MHz with 70% duty cycle, 1V min, 3V max. I am not sure this is OK-- it seems like CLK should be getting higher...

It appears that this is normal. Just so many TTL circuits between +5V and GND on this board. https://tinkerdifferent.com/threads/macintosh-iici-5v-to-gnd-resistance.4117/ My next step will be to measure the CLK (C32), RESET (C1), ACK (A28), START (C28), and TM0/1 (A5, C5) signals on slot E with...

Slot ID pins are also correctly set (pins A26 and C26) as C: ZZ; D: Z0, E: 0Z.

Ok. Reviewing the NuBus spec sheet and this partial schematic I found: https://www.macdat.net/files/pdf/apple/schematics/bomarc/mac_iici.pdf, I verified that the +12V, -12V, GND, and +5V connections are all continuous, low-resistance to the correct power filtering capacitors. However, I did...

Thank you for your ideas. I meant that I verified that the replacement battery was sending it's voltage to the mainboard. I've had these adapters sometimes not properly seat in the PRAM battery holder and make intermittent contact. That isn't happening here. I have also verified that when...

I am struggling to get my IIci to detect/use NuBus cards. I have a Radius PrecisionColor 8-24X, three different Ethernet cards, and a Radius Rocket. None of them seem to do anything in any of the slots. It's as if they aren't even there. The Rocket gets warm (slots appear to be properly...

I'd do continuity and resistance tests on the suspect traces. If they aren't great, you could bypass them. But, they really don't look bad enough to me to be broken, unless some damage is hidden. I would just give the thing a really good cleaning -- some little fleck of metal or broken wire...