Takky power supply question

Mods, can you delete one?
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Drew

Done! -eeun

A couple things I didn't mention, but I'll include for completeness.

I didn't connect the button board as I intend to use the 630's buttons and IR module (also unconnected). I didn't connect up the floppy drive, but I did connect an IDE drive. I've removed the SCSI ribbon completely. I can't imagine that any of that would make a difference, though.

Thanks!
Drew

The 'standard' approach to adding extra PSU capability has been to use the CC's PSU (ie the A/B) to power the logic board, and use any extra power supply to drive the HD. The mains to the extra PSU piggy-backs off the back of the usual mains i/p to the a/b, and the output is controlled by a relay activated by the normal a/b supply. This avoids the problem of starting an auxilliary PSU.

In your case, there must be a 'sense' i/p of some kind to the PSU from the 630 l/b. That may be level or edge triggered. I'd reinstall the PSU in a 630 and see what happens to various lines when you power the machine up.

Stuart

One of the walls I kept hitting when building my Takky was I didn't have enough of a load on the second PSU for it to supply power.

The required load I'm sure varies from supply to supply, but you might want to try triggering your 630 power supply separately with their intended load before working out how to trigger the 630 PSU from the CC.

I had the second PSU - a small one from All Electronics - supplying my hard drive, and supplying 3.3V for the 6360 board's PCI functions. It wasn't a soft-on variety, so I just used a relay connected to the analog board's 12V line.

Thanks to both of you. If I'm hearing you right, you're indicating that the CC analog board supplies enough power for a PCI-class board. Is that true even if running a full load of dual PCI cards, G3 upgrade, 128 MB RAM, AV module, TV/FM tuner, and Comm slot ethernet card? If so, I'll skip the 630 PSU as it's overkill for just powering a hard drive.

I've got a smaller PSU on hand for an external SCSI enclosure that wil fit just great. I've already tested it to make sure it comes up even without a load, so no problems in getting it started there.

I'm still a little confused, though. I was pretty sure that the 630 supply wouldn't come up no matter what without the ADB trigger. I've seen that these have been used in CC/Takky mods before, so I'm curious how those people get them started. Is this understanding wrong? Does the 630 PSU not need an ADB trigger?

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Drew

You might get away with the CC's own PSU, however depending on the logic board, you may need 3.3V from a second PSU (unless you use a regulator instead).

I recall someone mentioning long ago that while it may be possible to drive a lot from the CC's analog board, the additional strain may shorten the board's lifespan.

edit:I did rediscover John Stocker's page, as well as Chris's FAQ, and both mention the 630 supply being triggered from a relay.

Greetings!

When I built my 6500 Takky I've tried to get away without the additional PSU at first. It will somewhat function without it, but there are several limitations that come with it. The 6500 board will run without the regulator, but if you want to use the cache card or i.e. a G3 CPU Upgrade card, you will need the additional 3.3V supply. The system will not start up if these are installed and you don't have the 3.3V. Also, what I've noticed is without additional power hooked to the logic board, the physical strain is noticable. I had white lines running across my screen and when the hard disk was accessed, the screen would slightly dim and flicker. The same with network activity. Therefore, I would really recommend to wire in the additional PSU! After I installed one in my Takky, all these problems disappeared and the screen refreshes smoothly without any problems.

Cheers!

BeniD82

Of course, I do intend to use a 2nd PSU. I have two confusing points:

1) How can you start a 630 PSU by relay if it isn't connected to ADB?!
2) Are the 5V and 12V supplies from the analog board enough for a fully equiped PCI logic board?

Note that neither question pertains to the 3.3V supply or to hard drives. I plan on running those off a second PSU. Depending on the answer to question 1, that PSU may be a 630 PSU which is definitely strong enough (overkill, even) for one HD and the 3.3V supply.

Thanks for all the help so far! The CC community is awesome! John Stalker's page is where I got the idea of running the logic board off the 630 PSU. Maybe I'll just email him directly...

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Drew

. . . that way there are no 'turn on' issues - you just turn on from a relay from the a/b supply.

I generated 3.3v from the a/b's 5v line, and my Takky ran without an extra PSU. But I had no extra PCI cards, apart from the cache card.

Stuart

So John Stocker's email address bounces. Go figure.

But a closer reading of his website indicates that he left the ADB lines to the 630 PSU intact from the wiring harness and didn't connect them to the CC analog board.

But the CC has a pseudo-soft power PSU. Doesn't it need the ADB signals active to power up and light the CRT or does it always apply voltage to the CRT so long as the power switch is on? Anybody know? It seems like whenever I flick the switch on the PSU, I hear the CRT charge up. So I'm guessing that the A/B always applies power to the CRT if the switch is in the "ON" position... That could be handy.

Next question: Is a 6400/6500 PSU the same size and shape as a 630 PSU?

Peace,
Drew

I've been contemplating putting my Mac Mini into a new case, and I have an old Quadra 630 laying around that seems suitable. So I've been searching for how to activate the 630's PSU like you have.

Anyway, after being unable to find an answer, I decided to just... experiment. Seems like shorting pins 3 and 5 does the trick (pin 1 being the closest to the edge to the circuit board, and 6 being next to the fan connector).