[comp.sys.mac.hardware] External Casing for Internal Hard Drive

haney@tramp.Colorado.EDU (HANEY PATRICIA J) (04/29/91)

I want to get a very small portable casing for my internal drive.
I know all about the zero footprint casings, but my question has
much more to do with power requirements and loads for Mac computers.

The casing I want to get is made by Advanced Gravis and there is no
power supply. Instead it draws power from the floppy port using a
cable between the drive and the floppy port. This works because I
know at least two companies selling their own hard drives with such
a set up. The advantage is the reduction in size, portability, and 
easy connect-up.

Here is my question: Will a equipment-loaded Mac be able to handle
the extra power demand or would adding this kind of drive set up
be the straw that broke the camel's back and blow or otherwise damage
the power supply?

IDS/Jasmine make an extremely small drive that pulls power from the 
floppy port, but supposedly the drive only requires 2-4 watts.
Advanced Gravis sells a similar drive, but the power requirements
are listed as 6-12 watts. Apple told me pulling this much power on
a Mac that already has an internal floppy and an internal hard drive
is definitely not recommended, but were fuzzy on whether it's *not
suggested* or *will definitely damage the machine*. 

The power requirements of my internal drive in question are 5/12 volts
and 8 watts. I want to be able to take my drive in the above mentioned
casing and plug it *safely* into any Mac (using the floppy port for 
power), including the new Macs with their low power problems. Would
this drive set up be safe even with the most draining configurations,
such as a dual-floppy SE with an internal hard drive, or a IIsi with
a expansion card pushing it near it's power limits?

Comments, suggestions, facts are all greatly appreciated. Either post
or mail to me directly - I'll summerize what I can...

Thanks!
Trish
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