68kMLA Classic Interface

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Mac IIfx
Posted by: ironborn65 on 2023-05-05 00:54:38 Hi mates, this is a good period ... I got a Mac IIfx, not bombed with no caps leakages. It's in its way, so I have only pictures at the moment. I see there is a: - Apple 820-0400-06 630-0400 Macintosh Display Card with expansion SIMMs - Nubus rev 3 Network card with RJ45, no precise identification I know there are missing capacitors, but for me it's a good news, someone did not continue the restoration. Let's see ...
Posted by: joshc on 2023-05-05 02:13:01 I don't think there's missing capacitors - the IIfx has solder pads for both tantalum and electrolytic capacitors, so it's two sets of pads for each capacitor on the board. Looks like your board has tantalums already. Sometimes there are 2 leaky electrolytics in the start up circuit (top right of the board, near the RAM slots) which need replacing.
Posted by: ironborn65 on 2023-05-05 03:25:29 yup, thanks, you'r right https://recapamac.com.au/macintosh-iifx/
Posted by: joshc on 2023-05-05 04:47:34 No, not the yellow axials - those do not need to be replaced usually. Just the small aluminium electrolytic can-style ones, these:
Posted by: ironborn65 on 2023-05-05 05:16:33 it's already a tantalum in mine so, once cleaned it might work out of the box ... assuming the PSU is fine (unlikely)
Posted by: joshc on 2023-05-05 05:59:38 PSU is usually OK in these actually, never had a bad II/IIx/IIfx PSU yet. Fresh batteries and it may just work.
Posted by: olePigeon on 2023-05-05 07:55:39 I recommend replacing the C1 capacitor with a 25v or higher rated capacitor. You risk blowing a little crater there when turning it on.
Posted by: CC_333 on 2023-05-06 22:59:37 PSU is usually OK in these actually, never had a bad II/IIx/IIfx PSU yet. Fresh batteries and it may just work. That's a rare feat for Macs this old nowadays! They are requiring so much effort just to power on anymore, that I'm feeling like simply using them has become somewhat less enjoyable than it used to be. c
Posted by: joshc on 2023-05-06 23:43:07 That's a rare feat for Macs this old nowadays! They are requiring so much effort just to power on anymore, that I'm feeling like simply using them has become somewhat less enjoyable than it used to be. c I dunno, I'd say my IIfx machines have been among the most reliable in my collection. Never had to do any PSU work with them, and only very basic logicboard repairs. SE/30s and Classics on the other hand, a bit of a nightmare to keep going and the Colour Classic, even more of a pain.
Posted by: ironborn65 on 2023-05-10 04:20:34 I got it home, amazing machine! No electrolytic caps, PSU is fine ... "boong", happy chime 🙂 EU 165 with NIC card + Apple video card + keyboard, the case is yellowish but without damage, it comes from a law firm office oh + FDD + 5.25 HD, these are still to be tested but first a thorough cleaning! I'll evaluate the @olePigeon suggestion about C1 replacement before turning it on again
Posted by: joshc on 2023-05-10 05:00:24 Nice one! That is a lovely clean looking example.
Posted by: ironborn65 on 2023-05-10 05:04:26 I will add a spare SE/30 32bit clean ROM I have
Posted by: Phipli on 2023-05-10 05:05:56 I got it home, amazing machine! No electrolytic caps, PSU is fine ... "boong", happy chime 🙂 EU 165 with NIC card + Apple video card + keyboard, the case is yellowish but without damage, it comes from a law firm office oh + FDD + 5.25 HD, these are still to be tested but first a thorough cleaning! I'll evaluate the @olePigeon suggestion about C1 replacement before turning it on again View attachment 56358 View attachment 56359 View attachment 56360 View attachment 56361 View attachment 56362 If you drop two 256k VRAM SIMMs in that video card, it will do 24bit colour at 640x480. It is unaccelerated, but good enough for most things. I will add a spare SE/30 32bit clean ROM I have The stock IIfx ROM is already 32bit clean?
Posted by: joshc on 2023-05-10 05:06:52 The stock IIfx ROM is already 32bit clean? This. The IIfx is a no-nosense, grown up's machine with a clean ROM. No monkey business here.
Posted by: ironborn65 on 2023-05-10 05:31:26 got it! 🙂, tks you all VRAM: no 512k supported? VRAM speed: 70ns or 80ns?
Posted by: Phipli on 2023-05-10 05:36:12 VRAM: no 512k supported? VRAM speed: 70ns or 80ns? 512k SIMMs will function, but only as 256k SIMMs. 100ns or faster off the top of my head. Edit :
Posted by: Kevinlenane on 2023-07-30 19:07:45 I recommend replacing the C1 capacitor with a 25v or higher rated capacitor. You risk blowing a little crater there when turning it on. I just did this - comp still booted but with a nice solar flare.
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