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Home Forums 68kMLA SCSI2SD - External Bus powered, From termination power. — #1
Post #1 by uniserver
Source Forum68kMLA
CategoryPowerPC
Post DateTue, 3 Mar 2015 - 21:33
Original URLhttps://68kmla.org/bb/threads/scsi2sd-external-bus-powered-from-termination-power.1420/
Post
Screen Shot 2015-03-03 at 4.36.21 PM.png

I have not done this yet, but it sounds to me very promising.

the thought of popping onto the rear DB25 port and nothing else needed..!

that is almost as useful as USB.  all the mac's come with a scsi port on the back from the plus all the way to the G3 Power Mac

And even the plus, from what techknight mentioned, has termination power when you install the diode that is missing from the pcb.

I talked to Mike, he is pretty sure with a slight mod to the board i can run the whole thing from termination power.

:)

From Mike McMaster, designer of the SCSI2SD

27/01/15 - Running the whole board on termination power could be possible. The board would need to use MUCH bigger capacitors to make this possible.  You could try this on your own board by removing D1 and replacing it with a solder bridge, then soldering a large electrolytic capacitor on the board, either at J7,  J11 or J8 (or all three ?). J7/J11/J8 all of a 5V and ground pin on standard 0.1" spacing.
lol i just now saw this...  On Mike's Website LOL!!!!!   good for him.

Screen Shot 2015-03-03 at 4.30.10 PM.png

http://www.codesrc.com/mediawiki/index.php?title=SCSI2SD

Maybe i was the one that helped this idea along?  haha.

mp.ls