68kMLA Classic Interface
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| Click here to select a new forum. | | se/30 sound dies off | Posted by: imactheknife on 2022-12-15 17:52:58
Just curious. Se/30 sound worked great. Started noticing static sound, then checked and sound no longer worked. I restarted, no chime. I tried in another chassis, chimed, sound worked for a bit then same, nothing. I checked over everything, cleaned sound chips, reflowed back of chips, checked sound chip schematics for continuity and all is good. Headphone not working though. Must be related? | Posted by: imactheknife on 2022-12-15 18:03:00
reflowed my caps, cleaned again, all seems well.. | Posted by: mari3311 on 2022-12-24 00:10:51
Pin 7 on the J12 connector is often broken at the base of the pin.
Check the continuity between the tip of pin 7 of J12 and pin 4 of UA9. | Posted by: billbucks060 on 2023-12-01 02:23:44
Hi,
My Mac SE30 sound doesn't work either.
I tried with a different speaker -> no sound. I tested the built-in speaker with a different source, it works. If I plug headphones, I hear something but the sound is very low.
The capacitors seem to be ok. | Posted by: Phipli on 2023-12-01 02:55:03
Hi,
My Mac SE30 sound doesn't work either.
I tried with a different speaker -> no sound. I tested the built-in speaker with a different source, it works. If I plug headphones, I hear something but the sound is very low.
The capacitors seem to be ok. Has it been recapped? | Posted by: billbucks060 on 2023-12-01 03:14:46
No but I guess I have to go through it (found this: https://recapamac.com.au/macintosh-se-30/)
Is it fairly easy to do if you gently twist the capacitors to remove them or very risky for those who've done it ?
Is there a specific capacitor that should fix the sound issue as an attempt not to replace all capacitors ? | Posted by: Phipli on 2023-12-01 03:27:43
No but I guess I have to go through it (found this: https://recapamac.com.au/macintosh-se-30/)
Is it fairly easy to do if you gently twist the capacitors to remove them or very risky for those who've done it ?
Is there a specific capacitor that should fix the sound issue as an attempt not to replace all capacitors ? At this point in time, you have to get any SE/30 recapped. They're all failing and it is easier to recap a tidy machine than repair a bad one, although given your sound is playing up, I think it sounds like your caps are leaking and there is already some damage to the board.
Leaking caps aren't as visible as many people seem to think, if the board is dusty, you sometimes see a light oily discolouration on the dust, on a clean board, you have to look extremely closely. Tell tale signs are solder pads are dull, not shiny and mottled spots / blotches in traces.
Use lots of light, possibly a big window, and magnification. What I do is take a zoomed in photo with my phone, because the blotches can be hard to see. | Posted by: billbucks060 on 2023-12-01 03:31:46
Thanks for the info. I will order some new capacitors and replace them.
Is the better approach to remove them is to apply heat and twist with a plier ? | Posted by: Phipli on 2023-12-01 03:34:20
Is it fairly easy to do if you gently twist the capacitors to remove them or very risky for those who've done it ? It's pretty easy to remove them by the twist method. Just don't slip and gouge the board. I use needle nose pliers, apply a bit of downward pressure (it helps avoiding accidentally lifting a cap too soon). It usually takes one or two full turns for the cap to release and they come easily. You'll be left with the two legs in solder on the pads and these can be removed with a dab of "No Clean" flux and a soldering iron at about 330°C.
Then clean up the pads using a bit more flux and some solder wick. Don't leave the iron on the pad too long, and don't let the solder solidify before you lift the wick - best to lift the iron and wick from the pad at the same time. If the pad has some corrosion on it that doesn't come off easily, scratch it a little with the solder wick, but never spend more than a out 5 seconds with heat on the pad, it softens the PCB and they come free.
Clean everything up with IPA (rubbing alcohol) before you start soldering on new caps.
Be warned that the black mark for polarity is different on different types of caps so make sure you get it right. On electrolytics, the stripe is on the negative leg, on tantalums, it is on the positive. Yes, this is crazy dumb. | Posted by: Phipli on 2023-12-01 03:34:51
Is the better approach to remove them is to apply heat and twist with a plier ? Just twist, no heat. | Posted by: billbucks060 on 2023-12-01 03:39:51
Thanks for the info. I'll keep you posted once I get the new capacitors | | 1 |
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