Mac IIci, dead after power on
Working on IIci I picked up at swap meet. Ex-Cisco, it's gonna be sweet. I read that the battery doesn't matter. Pulled it. Zero leakage. Pre-recap, no life. Post-recap, no life. (Re-capped machine.) 5v 500ma line is fine from the PSU 12v line is fine from the PSU 5v line is fine from the PSU Not sure about -12, but probably just audio? No power on chime. Screen is black, monitor wakes up. Haven't used the DB-15 to VGA 6 switch converter in ages but it worked last time. Powers on from keyboard or rear panel switch. I guess the first things to check are the CPU reset circuit and the clock. Any other pointers from Mac geeks? :-) Recapped the A1200 motherboard I picked up and it booted! Now trying to decide on keyboard options. - Ethan
Does this have the TDK psu? I don't know about yours but the IIlc are notoriously bad. I had one with not only bad caps but transistors too.
Of all things I think it has a GE power supply. Like a refrigerator. I had a double take on it. Eat your heart out Delta, this thing is juiced from the light bulb & locomotive people. - Ethan
I have two IIci's with Astec supplies. I recapped both and I guess I didn't clean them enough because both do this funky on/off thing like the power-on-circuit is oscillating. I'd just love to bypass it and use a toggle switch and be done with it. Rich -- Rich Cini http://cini.classiccmp.org http://altair32.classiccmp.org <http://www.classiccmp.org/altair32> On 5/10/21, 2:56 PM, "vcf-midatlantic on behalf of Ethan O'Toole via vcf-midatlantic" <vcf-midatlantic-bounces@lists.vcfed.org on behalf of vcf-midatlantic@lists.vcfed.org> wrote: > Does this have the TDK psu? I don't know about yours but the IIlc are > notoriously bad. I had one with not only bad caps but transistors too. Of all things I think it has a GE power supply. Like a refrigerator. I had a double take on it. Eat your heart out Delta, this thing is juiced from the light bulb & locomotive people. - Ethan
I have two IIci's with Astec supplies. I recapped both and I guess I didn't clean them enough because both do this funky on/off thing like the power-on-circuit is oscillating. I'd just love to bypass it and use a toggle switch and be done with it.
If you look up the people doing ATX power supply conversions there is information with those people on how to bypass the soft ware stuff. Are you sure the power supply itself doesn't need to be re-capped? In my case I only did the motherboard, but tested the output voltages. - Ethan
The PS itself seems fine, but it's been a while since I looked at it -- other projects have gotten in the way. Will need to double-check it of course. Rich -- Rich Cini http://cini.classiccmp.org http://altair32.classiccmp.org <http://www.classiccmp.org/altair32> On 5/10/21, 3:33 PM, "Ethan O'Toole" <telmnstr@757.org> wrote: > I have two IIci's with Astec supplies. I recapped both and I guess I > didn't clean them enough because both do this funky on/off thing like > the power-on-circuit is oscillating. I'd just love to bypass it and use > a toggle switch and be done with it. If you look up the people doing ATX power supply conversions there is information with those people on how to bypass the soft ware stuff. Are you sure the power supply itself doesn't need to be re-capped? In my case I only did the motherboard, but tested the output voltages. - Ethan
I was given a Mac quicksilver G4 with the power supply dead , it blew the 8 AMP fuse. I’ll be sure that the caps probably need to be replaced but usually the fuse doesn’t blow unless there is a short. I’m thinking that one of the switch mode transistors went bad. Does anybody have any experience with these, it is the Samsung power supply, the long one with two fans in back? Mike Rosen Sent from: My extremely complicated, hand held electronic device.
On May 10, 2021, at 3:34 PM, Richard Cini via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
The PS itself seems fine, but it's been a while since I looked at it -- other projects have gotten in the way. Will need to double-check it of course.
Rich
-- Rich Cini http://cini.classiccmp.org http://altair32.classiccmp.org <http://www.classiccmp.org/altair32>
On 5/10/21, 3:33 PM, "Ethan O'Toole" <telmnstr@757.org> wrote:
I have two IIci's with Astec supplies. I recapped both and I guess I didn't clean them enough because both do this funky on/off thing like the power-on-circuit is oscillating. I'd just love to bypass it and use a toggle switch and be done with it.
If you look up the people doing ATX power supply conversions there is information with those people on how to bypass the soft ware stuff. Are you sure the power supply itself doesn't need to be re-capped?
In my case I only did the motherboard, but tested the output voltages.
- Ethan
That's actually annoyingly common with some IIci/IIcx/Q700 supplies. There's (IIRC) a bad cap issue with the trickle standby supply that's not terrible to fix, though you might do better just looking up a new PSU. I think I gave my working one away to VCF folks when I moved in a big box o' busted IIci parts. If you can't find the fix procedure online, let me know, I can try to see if I have it bookmarked. - Dave
On May 10, 2021, at 12:21 PM, Ethan O'Toole via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
Working on IIci I picked up at swap meet. Ex-Cisco, it's gonna be sweet.
I read that the battery doesn't matter. Pulled it. Zero leakage.
Pre-recap, no life. Post-recap, no life. (Re-capped machine.)
5v 500ma line is fine from the PSU 12v line is fine from the PSU 5v line is fine from the PSU Not sure about -12, but probably just audio?
No power on chime.
Screen is black, monitor wakes up. Haven't used the DB-15 to VGA 6 switch converter in ages but it worked last time.
Powers on from keyboard or rear panel switch.
I guess the first things to check are the CPU reset circuit and the clock.
Any other pointers from Mac geeks?
:-)
Recapped the A1200 motherboard I picked up and it booted! Now trying to decide on keyboard options.
- Ethan
participants (5)
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David Riley -
Ethan O'Toole -
Richard Cini -
Sentrytv -
Wil Birkmaier