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LC Power Supply interchangeability?

Posted by: Mikerophone on 2022-04-01 14:36:50

Greetings!

I'm working on bringing a Quadra 605 (Performa 475) back to life; the power supply is dead. The one in there is a Dyna Comp 614-0028, with max continuous power output of 36W. I have found two from LC's, one with part number 699-0003 and 699-0153, with max output of 27W. Are these interchangeable? Will the older ones power a Q605 properly?

The Q605 has 36MB RAM. I have installed a 40 Mhz 68040 from a dead 840AV, and it ran swimmingly for about three years with that config before the PS gave up the ghost. I'd really like to get this running again if possible.

Any insights would be helpful.

Thanks!

Mike

Posted by: Nixontheknight on 2022-04-01 15:26:22

AFAIK, the power supplies from all pizza box LC machines are interchangeable. I have an LC III that has a power supply that has the same model number as the power supply of an LC II

Posted by: alectrona6400 on 2022-04-01 16:09:28

If you feel confident enough, you can probably replace the caps and it should work again. However, sometimes the problem isn't that easy of a fix...

Posted by: Mikerophone on 2022-04-02 05:32:28

Thanks for your responses! My soldering skills are iffy at best, so I'm not sure I'm up to the recap idea, but may go there if necessary.

I guess another way to ask this question: Does anyone's 68040-based LC (475 or Q605) have one of the 27W power supplies in it, or one with the part number 699-0003 or 699-0153? I understand that they're physically all the same (thanks for confirming, Nixontheknight!), I'm just wondering if the 68040 LCs need more oomph.

Posted by: Nixontheknight on 2022-04-03 09:47:49

Thanks for your responses! My soldering skills are iffy at best, so I'm not sure I'm up to the recap idea, but may go there if necessary.

I guess another way to ask this question: Does anyone's 68040-based LC (475 or Q605) have one of the 27W power supplies in it, or one with the part number 699-0003 or 699-0153? I understand that they're physically all the same (thanks for confirming, Nixontheknight!), I'm just wondering if the 68040 LCs need more oomph.

the 040 LCs don't need more oomph. Byte Knight (the sysop of CQII) put an LC 475 logic board inside an LC III, and it has worked with the LC III's power supply

Posted by: joshc on 2022-04-03 18:49:14

They did alter the spec of the PSU slightly (can't remember part numbers etc right now) for the 475 but it doesn't seem to need it. I've never had any issues swapping them between any model of LC.

Posted by: MacKilRoy on 2022-04-03 18:52:51

They did alter the spec of the PSU slightly (can't remember part numbers etc right now) for the 475 but it doesn't seem to need it. I've never had any issues swapping them between any model of LC.

Could Apple have been more worried about the upcoming PowerPC upgrade they wanted to offer those machines? And therefore bumped the spec so those would be supported better ?

Posted by: chue on 2022-04-03 19:47:22

Does anyone's 68040-based LC (475 or Q605) have one of the 27W power supplies in it, or one with the part number 699-0003 or 699-0153?

My Q605 has an Astec AA16251. The label states it is Apple part 699-0003.

Posted by: Juror22 on 2022-04-03 20:35:48

I'm just wondering if the 68040 LCs need more oomph.

I ran my Q605 with maxed memory, VRAM, a full 040, a network card and a real hard drive on a power supply borrowed from an LC III for several years and never had any issues. An anecdotal test, but still one that goes solidly in the plus column.

Posted by: Siliconinsider on 2022-04-03 21:03:36

I have 3 different models here, they are all interchangeable but they have different power ratings. Note that 040 machines likely needed the higher power output, it also depends of the hard drive and PDS expansion you plan to use, in order not to overload the supply. The -5V rail is generated for the serial ports.

Astec AA19140 / 614-0028
+5V 4.75A
-5V 0.075A
+12V 1.0A

Astec AA16251 / 614-0003
+5V 3.75A
-5V 0.075A
+12V 0.78A

TDK 699-0153
+5V 3.25A
-5V 0.075A
+12V 0.75A

Posted by: Mikerophone on 2022-04-04 08:23:44

Thanks, everyone! I appreciate it. I'll report on success once the Q605 is back up and running.

Posted by: Mikerophone on 2022-04-09 12:38:28

Happy to report the 614-0003 power supply (Astec) works like a charm. Unfortunately, my old drive was done, but I had another ready to go in. My 605 lives!

Posted by: FABIO on 2022-04-11 04:34:13

Hello,
I am new regarding "recap". I have. a Performa 475 and the PSU is dead (No voltage at the End +12, +5 and -5)
If I would try to recap it where should I start? Which Elco should I look for replacement first?
Thank you in advance
Fabio

Posted by: tecneeq on 2024-12-08 07:49:37

I am new regarding "recap". I have. a Performa 475 and the PSU is dead (No voltage at the End +12, +5 and -5)
If I would try to recap it where should I start? Which Elco should I look for replacement first?

All of them. Post a pic of your power supply if this is still an issue you want to solve.

Another option, if recapping is not possible, or sadly comes too late, is this power supply:

Mean Well RPT-60A

Mean Well RPT-60A AC-DC Triple output Medical Open frame power supply; Output 5Vdc at 4.4A +12Vdc at 2.2A -5Vdc at 0.55A; 2xMOPP; compact size 4 x 2 inch

www.meanwell-web.com

3D printable mounting frame for a Dyna Comp PSU:

Apple LC Dyna Comp DCF 353 PSU Meanwell RPT-60A mounting plate by Retro Frog | Download free STL model | Printables.com

This mounting plate allows you to install a new Meanwell RPT-60A PSU inside a worn out Dyna Comp DCF 353 PSU. | Download free 3D printable STL models