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Author Topic: A1200 power through the floppy molex connector?  (Read 2404 times)

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Offline TheGooseTopic starter

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A1200 power through the floppy molex connector?
« on: March 14, 2009, 09:17:55 PM »
Um, this works fine it seems. Are there some caveats to rigging your A1200 this way?

Thanks for info...

G1200, A3000D, A1200 PPC AOS4.0C

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Offline save2600

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Re: A1200 power through the floppy molex connector?
« Reply #1 on: March 14, 2009, 09:30:45 PM »
Sounds like you're going 'in' through the 'out' door so to speak.  LOL!

Does the audio work on your setup? Is there a -5v present?

What did you do... jury rig a PC power supply to it?


 

Offline AmigaMance

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Re: A1200 power through the floppy molex connector?
« Reply #2 on: March 14, 2009, 09:44:51 PM »
 You mean powering your Amiga *only* through the floppy connector? I tried it once and my Amiga didn't even boot. My configuration is similar to yours.
 
A1200 PPC user.
 

Offline TheGooseTopic starter

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Re: A1200 power through the floppy molex connector?
« Reply #3 on: March 14, 2009, 09:47:50 PM »
Well, I did. Jumped an ATX PSU and hooked it up to see if this old MB worked. It came up just fine to the ROM screen.

I knew about this from my main PPC machine. Phase 5 would recommend you do this with the Blizzard PPC. So, if that couldn't hurt, why would it here I reckoned; famous last words...

 :lol:
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Offline doctorq

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Re: A1200 power through the floppy molex connector?
« Reply #4 on: March 14, 2009, 10:25:38 PM »
Quote

Well, I did. Jumped an ATX PSU and hooked it up to see if this old MB worked. It came up just fine to the ROM screen.


There is no problem in doing this, but you will have sound issues unless you hook a -5V supply to the machine.

Running the machine with only this power source with a variety of expansion might not be a clever idea.
 

Offline TheGooseTopic starter

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Re: A1200 power through the floppy molex connector?
« Reply #5 on: March 14, 2009, 10:52:23 PM »
Ah, that's the advice I was looking for, thanks.

Off to amigakit again...
G1200, A3000D, A1200 PPC AOS4.0C

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Offline AmigaSoft

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Re: A1200 power through the floppy molex connector?
« Reply #6 on: March 15, 2009, 11:00:24 AM »
I did this last week, Had to use an A500 power suply though to get the A1200 to boot.
CBM Amiga A1200
 

Offline delshay

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Re: A1200 power through the floppy molex connector?
« Reply #7 on: March 15, 2009, 01:05:16 PM »
-12v is missing in this thread,not unless someone is doing something special to use -5v.
-------------
power is nothing without control
 

Offline brianb

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Re: A1200 power through the floppy molex connector?
« Reply #8 on: March 15, 2009, 04:12:07 PM »

I personally wouldn't bring in power through the floppy connector...

My $0.02...

- You may be bypassing some important power conditioning circuits.

- You won't bring in the -12v line, which is probably necessary for the audio and serial circuits.

- You won't have the earth ground line.  Maybe not a big deal, but could possibly cause some audio noise.

The standard power supply on the 500/600/1200 has the following lines...

+12V
-12V
+5V
Ground
Earth Ground

I learned a lot about the PS building my "mega" power supply  for my 1200...

http://www.amiga.org/gallery/index.php?n=2905=10



 

Offline brianb

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Re: A1200 power through the floppy molex connector?
« Reply #9 on: March 15, 2009, 04:13:34 PM »

I personally wouldn't bring in power through the floppy connector...

My $0.02...

- You may be bypassing some important power conditioning circuits.

- You won't bring in the -12v line, which is probably necessary for the audio and serial circuits.

- You won't have the earth ground line.  Maybe not a big deal, but could possibly cause some audio noise.

The standard power supply on the 500/600/1200 has the following lines...

+12V
-12V
+5V
Ground
Earth Ground

I learned a lot about the PS building my "mega" power supply  for my 1200...

http://www.amiga.org/gallery/index.php?n=2905=10



 

Offline delshay

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Re: A1200 power through the floppy molex connector?
« Reply #10 on: March 15, 2009, 04:54:20 PM »
*correct* i have no idea where -5v was used on the amiga unless it was added in for something special.
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power is nothing without control
 

Offline orange

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Re: A1200 power through the floppy molex connector?
« Reply #11 on: March 15, 2009, 05:26:09 PM »
just don't ever use two PSUs, it will fry your Amiga.

Also, the PCB 'traces' for floppy power are probably not designed for so much current, so it would be better to connect both 'points' (with same PSU).

I did it once for testing and A1200 did boot.
Better sorry than worry.
 

Offline doctorq

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Re: A1200 power through the floppy molex connector?
« Reply #12 on: March 15, 2009, 05:33:31 PM »
Quote

-12v is missing in this thread,not unless someone is doing something special to use -5v.


A slight misprint from my side; it's -12V, not -5V. The other post got me confused there for a second.