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--- blog:mac_iici_refurb [2020/07/27 20:14] – [Capacitor List] john
+++ blog:mac_iici_refurb [2020/07/30 17:01] – [Testing] john
@@ Line 54: / Line 54: @@
 A list of capacitors and ratings is available on the [[https://wiki.68kmla.org/Capacitor_Replacement#Macintosh_IIci_.28another_revision.29|68k Mac Liberation Army wiki]], but I'll list them here anyway:
+Tantalum:
-    * **11x* 47µF, 16v (Tantalum)
+  * **11x** 47uF, 16v
-    * **2x** 10µF, 16v (Tantalum)
+  * **2x** 10uF, 16v
-    * **3x** 470µF, 16v (Electrolytic)
-    * **1x** 220µF, 16v (Electrolytic)
+Electrolytic:
+  * **3x** 470uF, 16v
+  * **1x** 220uF, 16v
 Some IIci boards vary, so there may be one or two less/more of the quantities listed. But those are the main ratings needed.
@@ Line 66: / Line 69: @@
 **[Update July 26th 2020]** - Ordered a set of replacement capacitors and waiting for their delivery.
+===== Removing Failed Capacitors =====
+Original capacitors still in place; some of them are showing clearly visible leakage:
+{{:blog:img_1657.jpg?400|}} {{:blog:img_1658.jpg?400|}}
+{{:blog:img_1659.jpg?400|}} {{:blog:img_1660.jpg?400|}}
+Original caps removed:
+{{:blog:img_1661.jpg?400|}} {{:blog:img_1662.jpg?400|}}
+{{:blog:img_1663.jpg?400|}} {{:blog:img_1664.jpg?400|}}
+{{:blog:img_1666.jpg?400|}} {{:blog:img_1667.jpg?400|}}
+Of the dozen or so capacitors removed, I lost a single solder pad on one of them, and I've had to scrape away some of the solder mask and bridge it to one leg of the capacitor - it's the right audio channel, near the 3.5mm stereo output jack.
+===== New Capacitors Fitted =====
+{{:blog:img_1665.jpg?400|}} {{:blog:img_1668.jpg?400|}}
+Not my neatest work, but I found I was out of desolder braid when I came to start the work, so it's as good as it can be, based on the circumstances.
+===== Testing =====
+And to prove it works, here's a recording of the actual system powering up:
+{{jPlayerPlaylist>mac_iici_-_audio_cap_repair.mp3}}
+I don't think I've //ever// heard it as clear as that! :-D
+A weird thing happened however on reassembly of everything...  (at least) one of the SIMM modules failed, resulting in the 'chimes of death' as heard above. I swapped them out with some spares and everything was happy again. Not sure what caused that, but the audio output remains clear as expected.