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#1 2015-07-14 13:18:36

IIfx
Member
From: VA, USA
Registered: 2014-09-07
Posts: 91

My IIfx is ill D:

It seems I just cant get a break when it comes to failing equipment. Now my IIfx is having issues - it seems the PSU is unable to provide enough power for the system to be stable with more than 2 Nubus cards. Network traffic almost always causes a reset loop. Weirdly enough just a Radius Rocket and Radius graphics card causes no issues, but if I go over 2 cards there is a high chance the system will suddenly reboot on its own under load, and then never finish booting (constant resets).

Here is a video of it suffering from the reboot loop of death:
https://www.youtube.com/watch?v=xEf8C2F … e=youtu.be

When I first got this IIfx it would only have these issues with a super hungry HDD, but it is happening with a low-power IBM drive now.

I am guessing this is a case of old capacitors hitting the end of their service life. Most of the logic board has tantalum's but the caps in the PSU are the standard type.

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#2 2015-07-14 16:47:29

max1zzz
Member
Registered: 2014-05-18
Posts: 207
Website

Re: My IIfx is ill D:

Yep, sounds like the caps in the PSU are bad. I had a a similar thing with my LC II (Except it was only the hdd that was cutting out not the hole LC) Recapping the PSU fixed it

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#3 2015-07-14 17:16:49

unity
Member
Registered: 2015-01-09
Posts: 81

Re: My IIfx is ill D:

Ya, probably PSU. I would swap out the few mobo caps too though that are not tats. If I recall there are three, two tin cans and a axial, but its been a while.

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#4 2015-07-14 19:37:58

volvo242gt
Member
From: Duvall, WA
Registered: 2014-05-22
Posts: 404
Website

Re: My IIfx is ill D:

Agreed.  Mine only had two non-tant caps on the board.  Now it's 100% tant.

-J


68K: Q650 48/1.2G/CD
modern: Mac Pro 2.8GHz 8-core 6GB/500G/DVD-RW, A1150 MBP 2GHz CD, 2GB/80G/DVD-RW
Pre-Mac: ][+, //e
other: iPhone 6s 128GB Space Gray

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#5 2015-07-14 19:39:57

uniserver
Member
From: Sf, Mi
Registered: 2014-05-15
Posts: 955
Website

Re: My IIfx is ill D:

I just got some 10,000 MFD caps in for those.  i can re-cap it for ya.
you can pm me if you are interested.


#I Re-Cap √Mac √NeTX √Amiga Boards - A/B - PSU# (MacCaps.com)  Modern SCSI HD's - For Old Macs - Pre Cfg'd - 10k RPM! 73gb!! $50 + free shipping  -- Mac 128K Re-Ram kits (16 Chips) $35 + shipping, Floppy Issues?-> Bourns Filter Solution 128k - SE/30, $16 + shipping

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#6 2015-07-15 00:05:53

techknight
Member
Registered: 2014-05-22
Posts: 449

Re: My IIfx is ill D:

Well 2 things here. Well, actually 3.

1 is the capacitors in the output rails of the power supply. But....

2: could be the opto-isolator going bad in the feedback circuit, or 3: the capacitor filter network on the feedback for the current loop could be bad as well.

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#7 2016-02-06 21:14:28

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

This thread reminded me to drag my IIfx out of storage to see if I can wake it from the dead.  Originally it was working when I first got it, but later on it suddenly decided to not turn on at all.  I know the 'kickstart' battery can give up, but it seemed to be fine, and even feeding an alternate source into those pins made no difference.  Is there a particular sequence of things I should try?  Do I bother to change out all the caps for this condition or do I just try to get hold of a known-working power supply?

  On a side note, what is the best video card I can install in this thing if I get it working again?  It was a cool system while it lasted.  I had four Sonic Solutions SSP pro audio cards in it and it functioned fairly well as an 8 I/O setup with max DSP (These cards have their own SCSI bus built in).  Real-time stereo reverb and de-noise were a big deal that early in DAW history, and unlike a Pro Tools system it didn't have to render any fades to disk - these also played in real time over as many tracks as your drives could handle.  Would have been a killer system in it's day, as well as a "wallet-killer"!

Last edited by MacOS Plus (2016-02-06 23:56:43)

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#8 2016-02-06 21:59:58

volvo242gt
Member
From: Duvall, WA
Registered: 2014-05-22
Posts: 404
Website

Re: My IIfx is ill D:

Are the capacitors the electrolytics?  If so, go ahead and do them.  If they're tantallum, then you need another power supply.  Although, usually, when the caps go bad, the machine will boot, but can only be shut down by pulling the power cord.  Otherwise, it acts like an SE/30, sitting there with the "It's now safe to shut down your Macintosh" dialog box displayed on a black screen.  A Mac II power supply will work fine in a IIfx.  Just has a louder fan.

-J


68K: Q650 48/1.2G/CD
modern: Mac Pro 2.8GHz 8-core 6GB/500G/DVD-RW, A1150 MBP 2GHz CD, 2GB/80G/DVD-RW
Pre-Mac: ][+, //e
other: iPhone 6s 128GB Space Gray

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#9 2016-02-07 00:09:06

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

It's been sitting for a long time, but I just measured the batteries again and they're still good.  I have one good spare around anyway.  All the caps on the motherboard and inside the power supply are electrolytics.  I saw no obvious evidence of swelling or leakage.

  One kinda weird thing I noticed - when I measure voltage at the line fuses it shows up as 5 to 6 volts briefly and then fades down to zero.  Taking the test probe away for a couple seconds and then measuring again repeats this.  I figured there would be full line voltage showing at the fuses as soon as the cord is attached.  Is there something I'm missing?  I know these power supplies work oddly compared to other types.  Is the mechanical relay supposed to trip the power supply on and then latch, or is it just for the pass-through outlet?  Absolutely no voltage is present at the motherboard connector, which seems counter-intuitive if the battery on the motherboard is supposed to trip the supply on.

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#10 2016-02-07 02:41:10

volvo242gt
Member
From: Duvall, WA
Registered: 2014-05-22
Posts: 404
Website

Re: My IIfx is ill D:

Ok, then I'd go ahead and recap it, even though it looks good.  The tantallum cap solder pads are present on the board, so you can solder them on, then remove the electrolytics.

-J


68K: Q650 48/1.2G/CD
modern: Mac Pro 2.8GHz 8-core 6GB/500G/DVD-RW, A1150 MBP 2GHz CD, 2GB/80G/DVD-RW
Pre-Mac: ][+, //e
other: iPhone 6s 128GB Space Gray

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#11 2016-02-07 05:18:31

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

I've made some headway which has significantly narrowed down the problem.  I searched around the internet and found out how to kick-start the power supply manually.  It's so hilariously simple - build a pack of four AA batteries in series to make 6V.  Join the negative to any black wire on the power supply header (ground), then briefly touch the positive lead to pin 15 (Power Good), the white wire on the right-most end of the header.  Well, damn, it immediately sprung to life!  Now that I know the power supply is good, it's gonna save me a lot of hassle.

  Upon much-closer inspection I found a very small amount of corrosion in two places under dust on the right-hand end of the motherboard.  Those spots are both near two tiny surface-mount electrolytic capacitors.  (All the much larger electrolytic caps look completely fine, and should be given the machine worked 100% other than the necessary kick-start.  It even shut down correctly.) One of those tiny caps is right near the soft-power button at the rear corner and it looks like it might be minutely swelled.  If I can find the right tantalum replacements in my scrap pile I will install them and junk the other two.  It's completely ridiculous that they used tantalum caps everywhere else but these two spots.  Anyway, even if this doesn't fix the soft-power function at least I know I can make the 6V kick-start more permanent.  I'm thoroughly relieved that the trouble is so isolated.

  On the video card front, I'd forgotten the IIfx is where I'd last stuck my Radius Thunder IV GX 1600.  It didn't play nice with a number of other hardware configs I wanted in better machines, so I had settled on maxing-out the resolution ability of a single screen on the IIfx.  All the other slots are going to be full with the four audio plus SCSI accelerator/network hybrid card in a chained set of five, so there won't be any room for another video card.  That Radius card frequently caused problems by being an extreme power hog anyway.  I removed the DSP daughter-board a long time ago to help with this issue because I wasn't keen on using ancient Photoshop in such a slow system environment.  (Instead I use only a mildly ancient Photoshop 6.0 on Windows Vista because I'm still a major foot-dragger!)  I have at least three monitors around that will support 1600x1200 res so one of them oughta work.  Then, if I'm feeling greedy, I'll attempt the OS8.1 installation hack.  The hard drive in this thing is awfully slow (typically clunky old Maxtor), so I want to replace it anyway.  The current system installed is the max 7.6.1 which it arrived with from the previous owner.  The 32MB of RAM should be enough for what it's going to do.  As much as I'd like to get hold of some 64-pin 16MB SIMMs (and at a reasonable cost), I doubt it's ever going to happen.

  Once this system gets back to normal and has all the external rack-mount boxes for the audio connected I think it'll be quite photo-worthy.  I'll cross my fingers, then if it all goes according to plan I'll post pics of this monstrosity!

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#12 2016-02-09 05:04:29

gsteemso
Member
From: north of Seattle, USA
Registered: 2015-11-30
Posts: 11
Website

Re: My IIfx is ill D:

Somebody either is halfway through manufacturing, or has already had manufactured, new maximum-size IIfx SIMMs. I can’t recall whether it was on 68kMLA or on Mac68k, but it was definitely on one of the two and from what I remember they were amazingly inexpensive for what they are. Not involved in any way, just passing the knowledge along.

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#13 2016-02-09 06:15:57

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

gsteemso wrote:

Somebody either is halfway through manufacturing, or has already had manufactured, new maximum-size IIfx SIMMs. I can’t recall whether it was on 68kMLA or on Mac68k, but it was definitely on one of the two and from what I remember they were amazingly inexpensive for what they are. Not involved in any way, just passing the knowledge along.

I assume you're referring to this thread:

https://mac68k.info/forums/thread.jspa?threadID=363

  This would be great if it actually went anywhere.  I'm a sucker for maxing out RAM, and the original 16MB 64-pin SIMMs are essentially unobtanium now.  My IIfx does have 32MB already fortunately, which is probably fine for OS 7.6, but at least 64MB would be much better, especially if I get the thing going on OS 8.1.  The Sonic Solutions software I would be running exhibited a slow but steady memory leak in the Q950 systems I once worked on, leading to necessary periodic restarts of the program.  Those systems had 40MB RAM.  After suffering with the issue for a while I finally managed to scrounge more RAM from other unused Q950s in the studio tech shop storage to bump it up to 64MB, which at least allowed me to get in a whole day's work without a restart.  I'm sure the problem would be the same no matter what 68k host system was used, so 64 or 80MB RAM in the IIfx should be enough to delay the terminal point of the leak an acceptable amount.

  It looks like that SIMM project got as far as one person buying an entire spool of new RAM chips and getting a large run of PCBs made.  I'm not sure how he intends to proceed, but I certainly would like to be able to buy the materials from him to make at least eight SIMMs.  I have tiny-enough soldering irons to do the assembly work myself.

  Now if someone would also make new 16MB 30-pin non-composite SIMMs, I'd be super-happy.  I have use for a large number of them but need size consistency and reasonable cost.  The composite SIMMs won't fit together is sequential angled sockets, while the tall ones are useless for expansion cards that sit in neighboring slots together.

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#14 2016-02-13 21:43:42

gsteemso
Member
From: north of Seattle, USA
Registered: 2015-11-30
Posts: 11
Website

Re: My IIfx is ill D:

Eh, probably that thread, yes. If you have questions, you could just PM or email any of the individuals who have posted to it. Yes, that would require signing up for an account on that site, but it is not like that costs anything or is difficult. I would already have contacted someone myself if I personally owned a IIfx—as matters stand, my interest is purely academic, which is why I have no more helpful information for you.

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#15 2016-02-14 00:10:37

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

Okay, I'll happily join that forum and bug them!

  I was working at fixing my motherboard today.  The two small capacitors have been changed but had no effect.  They seem to be part of a different circuit.  I sorted out that the large capacitor near the front right of the board is probably responsible for kicking the power supply.  It stores the combined voltage of the two batteries, and it must be in good shape because it holds that voltage for a long time after either battery is removed.  I saw no evidence whatsoever of bad tracings.  The power for the trigger control circuit is somehow not reaching the main power button or the ADB ports but I can't tell were the break occurs.  If I had a schematic I might have a better idea.

  I've decided for now that I should probably leave it alone before I manage to wreck it.  I determined that simply using the positive lead from the large capacitor via a wire to trip pin 15 is effective.  I'll install an external push-button and be satisfied.  I noticed a small notch the previous owner had ground into the edge of the case near the front right of the right-hand floppy drive.  I don't know what they were using it for but it will make a perfect spot to fish the wires through for my hack-job push-button.

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#16 2016-02-14 17:22:10

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,379

Re: My IIfx is ill D:

I've got 32MB in my pet IIfx which seems to be plenty for anything I play with under 7.5.1. The CAD/Photoshop folks needed max RAM back in the day, but 32MB seems plenty for anything else on a IIfx.

In my case, installing 1995's OS 7.5.1 on the IIfx for its feature set makes some sense. But setting a IIfx up to run 1997's 7.6.1 has always seemed like a stretch to me in terms of "real world" retro Macs. I've never understood the SE/30 crowd's infatuation with latest and "greatest" OS upgrades. The IIfx itself was obsolescent at best at the very beginning of the Quadra era. But it was woefully obsolete by the time I bought my Quadra 630/7.2P with its free upgrade coupon for 7.5.

But that's just me. neutral

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#17 2016-02-14 20:45:33

LCGuy
Administrator
From: Sydney, Australia
Registered: 2014-05-13
Posts: 806

Re: My IIfx is ill D:

How was it "woefully obsolete" in 1994/1995? Keep in mind that Apple was still selling machines like the LC II and LC III at that point, neither of which can hold a candle to the IIfx.

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#18 2016-02-14 21:47:57

jt
Member
From: Bermuda Triangle, NC USA
Registered: 2014-05-21
Posts: 1,379

Re: My IIfx is ill D:

Comparing it to lowest of the low end LC Macs of 1994/1995 would hardly be relevant. Comparisons of the IIfx to higher end machines would be necessary. Even the 68LC040 hobbled "low end" Quadra 605 bested the IIfx in floating point operations. Comparing the IIfx to 1994's x100 series would be dubious at best, even the vaunted 840AV was put to rest in July of 1994. Comparing the IIfx to 1995's x500 series PowerMacs would be downright silly.

LOL! Just checked, the LCII was long gone by then, just barely making it into Q2 1993. Curiously enough, the 33MHz LCIII+ was discontinued exactly 22 years ago today on St. Valentine's Day in 1994!

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#19 2016-02-15 02:31:39

MacOS Plus
Member
Registered: 2015-12-09
Posts: 92

Re: My IIfx is ill D:

Ah, yes, the LCIII+ - The 'Canadian' edition.  Of course that's one of the reasons why I had to put one in my collection!

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#20 2016-02-15 07:16:07

LCGuy
Administrator
From: Sydney, Australia
Registered: 2014-05-13
Posts: 806

Re: My IIfx is ill D:

jt wrote:

LOL! Just checked, the LCII was long gone by then, just barely making it into Q2 1993. Curiously enough, the 33MHz LCIII+ was discontinued exactly 22 years ago today on St. Valentine's Day in 1994!

*shrugs* I could be wrong, but I'm fairly sure that they continued to sell LC II's and LC III's to the education market at least in 1994 - sales to regular consumers came to an end but I understand you could still buy a new LC II or LC III in 1994 as a school or a uni student.

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