68kMLA Classic Interface

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TAM

Posted by: falen5 on 2015-05-19 12:02:59 just tried to power it up ........no joy - zip!! - tried it with / without rom and cache card....nothing - im flying blind here people.............how do I turn it on!!!!!!!!! - I have no pram battery installed. I found the power button on the rear, left hand side, next to the main cable from the subwoffer - I see no activity of any kind, no led's, no sounds............. - what is the correct start up procedure.............hit the power button on the rear and then hit the top right key on keyboard - mmmmmmmmmmm...................will it even start without a pram battery at all?? - I didn't bother connecting the cd drive , the hard drive or the network card ......im pretty sure ive connected everything else - should there be an led on somewhere to show life...anything.............it is as dead as my hairline! - heelllppppp

Posted by: falen5 on 2015-05-19 12:18:13 found a similar battery from a lciii or something - same connector - tired it....still nothing - caps don't look good...........many have an upwards pointing dimple in the top........... - can I test the subwoffer for power on that big round connector?.....surely there would be 5 ,7 or 12 volts coming from it ?

Posted by: haplain on 2015-05-19 12:41:47 Doesn't need a PRAM battery to work/start. You can just press the power button on the back of the unit OR on the keyboard.  There is a CUDA reset button on the board you should press before you try to start it up. Sounds like it has a cap issue which might be the culprit.

Posted by: falen5 on 2015-05-19 12:54:19 just metered out the subwoofer cable and nothing - - should there be some signal coming from the powersupply to the machine ? - ive tried the reset and nothing - think ill just do a full recap before anything else - later

Posted by: unity on 2015-05-19 12:57:42 I never got around to re-capping mine yet. You might be the first to re-cap one if you do. I would check the power supply first, its fuse, etc...

Posted by: unity on 2015-05-19 12:59:38 By the way, the power supply is not auto-switching. Maybe I missed where you said you checked it, but if not check it. edit: There should be 5v standby power from the supply I would think. I can check mine later if needed.

Posted by: falen5 on 2015-05-19 13:13:05 hi unity. Yep I made sure its on 230 volts - the guy I bought it from told me about that as well. - ive opened up the subwoffer.......dam difficult......its held together with screws and double sided sticky tape - the sticky tape is all around top rubber and all the inside is lined with some other soft tape - avoid rattels from the bass I guess. - it looks like a standard power supply with a audio amp board on the side. - this subwoffer was dropped at some stage of its life. There is a 2 inch crack in the plastic cover on one side, and as I began to open it 2 of the screws turned, but the plastic they were screwed into was broken off inside and was turning with the screw. - I got it open without any futher damage. - - there is no sound from the power supply of any kind when I plug it in. usually there is a quit hum or something. I know the thing is in sleep mode waiting for the computer to switch it on......bit this thing looks dead to me - there must be a fuse inside that power supply, and seems it has obviously had a knock... im thinking the fuse has been dislodged - heres a few pics - whats your thoughts people

Posted by: falen5 on 2015-05-19 13:23:42 took out the powersupply and the bose audio board - not really much to it - looks like a standard powersupply with a output to plug in your monitor - ha ha ......caught ya apple... hiding power ports!!!    be jasus - gonna open the powersupply to see if there is a loose or blown fuse

Posted by: haplain on 2015-05-19 13:31:18 Yeah check the fuse and there isn't much on the Bose board to go wrong with from my understanding.

Posted by: falen5 on 2015-05-19 13:39:37 finally got into the powersupply - was covered with some foamy tape crap - had to cut through it - but anyway............found the fuse....6.3 amp   250 volt - and its dead!!!!!!!!!!!! - great stuff - in with a good one and slap this thing back together!!!

Posted by: falen5 on 2015-05-19 13:44:48 found a 250volt 8amp fuse in my external scsi.........that would be ok yeh?

Posted by: Byrd on 2015-05-19 14:19:57 Good finding - no, I'd match the fuse with same.  Note there is a green LED on the underside of the sub that'll tell you if powered

Posted by: falen5 on 2015-05-19 14:22:53 just had an explosion from the power supply......holy %^^%$£ - 8 amp fuse ...black and dead. - a few caps black and dead - at least I didn't have the tam plugged into it -

Posted by: falen5 on 2015-05-19 14:23:29 darn

Posted by: falen5 on 2015-05-19 14:40:00 new plan.......new power supply......ive blown the hell out of the old one - just checked and there are simmilar powersupplys on ebay.....but with different wiring - seems I have this blown powersupply with the correct wiring......I could just get a new one and move over the wiring - heres a link to one for sale - http://www.ebay.ie/itm/Delta-Electronics-DPS-150GB-A-Apple-614-0039-150W-Power-Supply-150-Watt-/141661288905?pt=LH_DefaultDomain_0&hash=item20fbabb9c9 - different apms........ - dam it!!!!!!!! -

Posted by: haplain on 2015-05-19 14:47:50 YIKES! Good luck man. I've got some of those PSU's out to be looked at and they are pretty special. Let me know what you can do with a swap as I might need that here at some point.

Posted by: falen5 on 2015-05-19 14:47:57 people..............im depressed - im gonna talk to the lepracauns....................... - as father jack would say........FECK!!!!

Posted by: techknight on 2015-05-19 15:47:11 Well, Usually when a fuse blows. 90% of the time that doesnt mean stick a new one in it and try again. they blow for a reason. Well, now you found out the hard way. Think twice! Most likely had a shorted FET, or bridge or something. coulda found it before swapping the fuse.

Posted by: bibilit on 2015-05-20 00:16:08 In my opinion, the Power supply is a modified 6500 unit. I was given a Powermac 6500 and only kept the Logic board, wiring and PSU because they all were close to the TAM's one. I think  the plug and wiring from the PSU should be the only difference.

Posted by: unity on 2015-05-20 00:23:11 Damn! Sorry to hear that. As technight said there is a reason. I am just surprised the fuse did not simply blow again.

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