68kMLA Classic Interface

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diode?
Posted by: falen5 on 2017-03-12 16:08:40
Can someone please tell me what this blown component was, and what i should replace it with (its just in front of the SCSI connector, on its left hand side)

I think it was a diode

its off an SE

I took this machine down to have a look. Turned it on, all was fine. Turned it off

Turned it on again to test the floppy and it wouldnt come on

opened it up to find this blown component

No idea how or why it blew.

I tell ya people, im getting worried about my old macs. Each time I take a few down to have a look there are always more problems

hhhhhhhhhhhhh.JPG
Posted by: falen5 on 2017-03-12 16:23:46
took it out

gave it a wash with some acetone to get rid of the cack

Think thoes 2 traces look ok

what ever happened here, this thing got real hot

IMG_9035.JPG
Posted by: 360alaska on 2017-03-12 19:57:34
Pretty sure that's the rectifier for SCSI termination power, a 1n4001 should be the replacement.
Posted by: techknight on 2017-03-13 17:44:09
Yes, thats the term power diode. 

It cannot blow unless the circuit was completed, being shorted-to-ground completed. 

So the internal hard disk drive caused that, or an external one did. One or the other. 
Posted by: falen5 on 2017-03-13 20:52:25
Thanks so much for the advice folks.

will have to take a look at the drive as well so.

right!.. wheres me glass'es !!
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