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Mac IIsi a fire hazard??
- Thread starter LC_575
- Start date
I thought so... I remember seeing a few IIsi units in my time and i only ran into ONE that had a ROM SIMM. rest did not.
Hmm
You're consistently getting the chimes of death now?
Death chimes don't always provide video. From my experience, <50% of real death chimes show anything on the screen. The Mac must still be fairly healthy if you do get the chimes, it requires a lot of good hardware to get that far. A severely damaged Mac will not chime at all. Also, your video adapter might not be configured right, or won't work with your particular monitor. Old Macs like the IIsi often lack standard sync signals.
Do you have the board installed with the blown capacitor? Make sure to try booting with that board removed. Also try cleaning the logic board. Most of my IIsi's came with major capacitor leakage.
You're consistently getting the chimes of death now?
Death chimes don't always provide video. From my experience, <50% of real death chimes show anything on the screen. The Mac must still be fairly healthy if you do get the chimes, it requires a lot of good hardware to get that far. A severely damaged Mac will not chime at all. Also, your video adapter might not be configured right, or won't work with your particular monitor. Old Macs like the IIsi often lack standard sync signals.
Do you have the board installed with the blown capacitor? Make sure to try booting with that board removed. Also try cleaning the logic board. Most of my IIsi's came with major capacitor leakage.
I do not have that card installed - of course I removed it. The motherboard appears to be pretty clean. I managed to get it to boot without death chimes, by removing all of the memory modules, and even read a boot floppy, but it halts after a point. Still no display - my adapter has multiple modes - would it be helpful if I posted a pic of it here?
Sure, that would help, maybe one of us could find a clue and provide more suggestions. Also, if possible, try it with several different monitors. I have a graphite Studio Display and an LCD that will NOT work with IIci or IIsi, yet I have a couple of other Trinitrons that work perfectly or partially (green/washed out/etc). Some screens are more picky than others.
The way it sometimes works and sometimes doesn't screams "bad caps" to me. I'd at least run it in the dishwasher to remove any invisible leakage and conductive particles. Or replace the caps. A sloppy power supply could also cause the crashing and capacitor explosion you've witnessed.
The way it sometimes works and sometimes doesn't screams "bad caps" to me. I'd at least run it in the dishwasher to remove any invisible leakage and conductive particles. Or replace the caps. A sloppy power supply could also cause the crashing and capacitor explosion you've witnessed.
Here's the ebay page for the converter I bought, the one in the pics is identical to what I have:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260625981691&ssPageName=STRK:MEWNX:IT
Currently I'm using an IBM monitor, my only spare, although i've got a Dell CRT in the garage I could drag out. I'll try it on that and my LCD's as well. Heck, I could even try it on my TV :lol: big screen System 7!
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260625981691&ssPageName=STRK:MEWNX:IT
Currently I'm using an IBM monitor, my only spare, although i've got a Dell CRT in the garage I could drag out. I'll try it on that and my LCD's as well. Heck, I could even try it on my TV :lol: big screen System 7!
I used to have exactly that video converter... what setting are you using? I would try the "13 inch 640x480" setting, not any of the multimode ones. I don't think the IIsi supports any higher than 640x480 (see Here. The IIsi can use *at most* 320k of onboard RAM for video. ) and it *may* predate the Macs that supported "normal" VGA monitors.
Fair warnings, LCD monitors may not care for the "13 inch" mode, but most CRTs should at least pretend to work.
Fair warnings, LCD monitors may not care for the "13 inch" mode, but most CRTs should at least pretend to work.
Perfect! Swap parts between the two to narrow things down, then you can have TWO working IIsis! Or at least plenty of spare parts.
Sir Bunsen: I believe you meant 2^6, but indeed 64 possible combinations is spot-on.
Sir Bunsen: I believe you meant 2^6, but indeed 64 possible combinations is spot-on.
This thread is getting too long and unweildly, but... did you try that? I don't know if the IIsi is one of them, but a number of 68k Macs won't produce video unless they have a working PRAM battery. (LCs fall into that category.)
Googling around it does appear that the IIsi uses composite sync rather than vga-standard seperate horizontal and vertical sync. Some (many?) Multisync CRTs can accept composite sync on their hsync pin, but since I don't own any machines that old I can't comment on whether that might be a feature that's becoming extinct. If you were looking for a monitor just for this purpose that's not the original equipment I'd recommend a medium-to-high-end early-mid 90's vintage NEC or similar. Anything made after 2000 or so I wouldn't *bet* on unless it was really high end. (IE, was made to work with UNIX workstations or the like.) A composite-sync friendly monitor is all that will work with a "gutless" adapter like what you have. They used to sell adapters which contained active components to seperate the sync signals so you could use monitors which didn't support composite sync... you may have a challenge finding one. (Apple apparently sold an adapter *themselves* to allow the IIsi to work with newer Apple monitors. Stacking one of those with your switching adapter might work...)
Or your monitors and adapter may be adequate and the machine is simpy dead. RIP?
You can put the adapter back in after you remove the blown tant. I know it's more risky running without the filtering but it should still be fine. The blast mark you saw on the main board was just residue from the tant when it was still smouldering. I had the same marks on a 5160 when it started blowing up tants all over the ISA bus but it still worked fine.
I owned a IIsi once and I do recall that the onboard video was very picky about monitor frequencies and resolutions so I just stuck with a mac display and got around all this multisync monitor BS.
I owned a IIsi once and I do recall that the onboard video was very picky about monitor frequencies and resolutions so I just stuck with a mac display and got around all this multisync monitor BS.
You should put it on the trading post, free + shipping. Someone may want parts or do a case mod, etc. It's a dandy little Mac.
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