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Home▸ Forums▸ 68kMLA▸ LCIII restored - It's Alive! + Questions for uniserver and people that know stu
Post #1 by lopaka1998
Source Forum68kMLA
CategoryHardware
Post DateSun, 12 Apr 2015 - 23:24
Original URLhttps://68kmla.org/bb/threads/lciii-restored-its-alive-questions-for-uniserver-and-people-that-know-stuff.1748/
Post
My LCIII is running once again!  Had lots of issues with this one, bad caps (obviously), a short on the +5 volt rail, and all that electrolytic stuff to clean up.  This one just didn't want to start.

First it was cleaned, and new caps for the board and power supply.  Nothing (except hdd turn on and fan spin-up).  So I cleaned it 5 more times... still nothing.  Recapped again with new caps.
Then I discovered a short to ground on the +5 rail.  Then I cleared the short.  Still nothing.  Then I replaced the caps again... and it finally started  :)    Lesson - never give up!

So my questions to uniserver and people that know stuff like techknight, bigmessofwires, mcdermd, etc.... 

Does anyone know what the normal operating temperature is on the cpu for the LCIII (not overclocked)?  Mine gets so hot that it almost burns my finger to touch it.  I am guestimating that it's about 110 - 120 degrees farenheit.  I don't remember them getting this warm - but it's been many years since I last had a working system. 

Second thing - caps c4, c5, c7 -  they all show about 3.3 volts is this normal?

Also cap c2 has no noticeable voltage - is this normal?  Maybe it's a high pass filter for the speaker or something?

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mp.ls