68kMLA Classic Interface

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Help required with Logic board component IIgs

Posted by: bibilit on 2019-05-04 10:25:48 I have been asked to have a look at a IIgs with a clicking PSU. Upon inspection, the 5 volt rail for shorted to ground, in the beginning my first thought was that a capacitor was shorted, but in the end, and after lot of trial and error, the culprit was located. Problem is, i can't find any information online. The component is in the upper left corner of the board, near the ADB connector (L2 on the picture), here are a couple of pictures, part is still available ? what is the purpose of this part ? The good news is that the IIgs is now displaying the usual "check drive" message

Posted by: Unknown_K on 2019-05-04 10:54:06 Data line filter, a few macs use them. I believe the part is : https://www.datasheets360.com/part/detail/d-16c/2564026962731279522/

Posted by: cruff on 2019-05-04 14:45:42 Since one side of each of the inductors inside that part goes straight to the ADB connector, it might be good to check that pin 3 of the connector itself isn't somehow sorted to ground.

Posted by: bibilit on 2019-05-04 23:20:03 I will.. Found a similar part on the SE/30 board (reference is almost the same) and since i have a pair of Maxel bomb destroyed boards, can i removed this part to save the IIgs ?

Posted by: cruff on 2019-05-05 14:55:34 You can double check the part on the SE/30 board by seeing if pins 1&8, 2&7, 3&6 and 4&5 have continuity.  Since they are inductors, the resistance shouldn't be very high.

Posted by: bibilit on 2019-05-05 23:19:22 Problem solved, removed the part from the SE/30 board and used it in the IIgs. The old part was shorted, no other problem found, IIgs is back to life.

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