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Alternative PSU for the IIsi?

zuiko21

Well-known member
Hi all,

I've got a couple of IIsi's -- case and mobo, but no disks or PSU. After washing, the MoBos work great (I used a Quadra 700 PSU on the bench) and I have several SCSI disks for them, but the IIsi Power Supply Unit seems very hard to get.

Any chance that another PSU (say, from a LC) would fit inside the IIsi case? I don't mind if I have to hack the connector, even if I lose the soft-power feature.

Which were the orginal specs (allegedly underpowered) of the IIsi PSU, just in case I could hack a non-Apple one?

Thanks a lot in advance!

 

ojfd

Well-known member
but the IIsi Power Supply Unit seems very hard to get.
Are they really that hard to get? Have you checked these suppliers?

http://www.retrotechnology.com/herbs_stuff/m_parts.html

http://www.recycledgoods.com/products/Apple-699-0567-IISI-Power-Supply-Sony-APS-06.html

Which were the orginal specs (allegedly underpowered) of the IIsi PSU, just in case I could hack a non-Apple one?
The one that I have and that looks like it came from IIsi has following specs:

Apple Part Number: 699-0567

+5V = 6.8A

+12V = 0.8A

-12V = 0.3A

+5V = 1mA (PSTRICL)

 

zuiko21

Well-known member
Are they really that hard to get? Have you checked these suppliers?http://www.retrotechnology.com/herbs_stuff/m_parts.html
Yes, but this one won't accept PayPal... postal money orders to the US are no longer available here, and a money transfer (Western Union?) will cost more than the price itself -- add the overseas shipping and the eventual customs clearance, and I may be paying four times the nominal price :(

They say 'Sorry but this item is currently unavailable' :( And the $64 tag after discount (but before shipping+customs!) makes it hardly a good deal...

On the other hand, PSUs for the Quadra 700-650/IIcx/IIci/IIvx/PMac 7100 are much more common (and cheaper). Almost the same goes for PSUs for the LC, 6100, 7500 etc.

The one that I have and that looks like it came from IIsi has following specs:
Many thanks! Here we are a starting point... That doesn't seem to be a lot of power, with modern technology it's likely that someone makes a suitable PSU small enough to fit somewhere inside the IIsi case...

All the best,

 

sunder

Well-known member
I recently took my IIsi out of the closet and attempted to power it on. Pressing the power button in the back produces a faint buzzing sound, and the power supply shuts off after about 1 second. I do see the power LED light up though it's dim, and the fan does spin.

So I take it the capacitors on the power supply bit the dust, but I don't see any bulging out. I don't see anything wrong with the motherboard, but that doesn't mean it's not the problem.

I'm wondering if someone here already replaced caps on a IIsi and whether they have a purchase list (or schematic) to save some time before I take it apart and figure out what the caps are and order new ones.

(Already replaced the 3.6V half AA battery, that wasn't it.)

 

sunder

Well-known member
Sounds good, but where do I get the pinouts for the Mac IIsi power connector?

Well, actually I'll probably want to replace all the caps in the PS to keep the original.

BTW, is anyone else finding IIsi's rare? I've not seen any on epay in maybe 5 years where they used to be common.

 

zuiko21

Well-known member
Mac PSU's pinouts:

http://www.xlr8yourmac.com/systems/MacinPC_ATX_case/images/PC-MAC_PS_pinouts.jpg

(wow, there's a link already :) )

The IIsi PSU has the same pinout of the IIcx-ci-vx, Quadra 650-700 and PowerMac 7100; but the form factor is different. You may try them on the bench, though.

If you're going to hack an ATX PSU and want to keep the soft-power feature, you'll have to put some form of inverter between the PFW line (Mac) and PS_ON line (ATX)

Anyway, have a look here if you want to repair the original PSU -- capacitors may not be the culprit...

 

bibilit

Well-known member
I've got a couple of IIsi's -- case and mobo, but no disks or PSU. After washing, the MoBos work great (I used a Quadra 700 PSU on the bench) and I have several SCSI disks for them, but the IIsi Power Supply Unit seems very hard to get.
Hi Zuiko21, i have got a spare IIsi i want to get rid off, i will keep the ram and floppy but probably not much else, if you want it you can have it for free... as long as you want to pay p&p from France to Spain.

I have tested it and know the psu is working properly, the disk was dead !!

Let me know, as i will probably get rid of it soon.

Un saludo.

 
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