Windows 7: External Hard disk

Could anyone please help me to make ma own external hard disk without external power supply.

Because its difficult to bring the power adapter always with the drive

sorry, but hard disks need some sort of power. they are mechanical and have motors.

maybe use a usb flash/thumb drive instead?

To convert a standard 240 volt external drive bay will be quite difficult, you will have to be very knowledgeable of electronics and be able to create a cable that will draw power from 2 or more USB ports and that is provided that the computer it is connected to is able to give the required amount of power
you can very cheaply(£60 260GB LTHDD and caddy) buy an external drive that runs from 2xUSB jacks or if you already have a laptop drive spare then just the caddy its self for around £20 - £30

Hi there
You can always run some disks from power from the USB so you don't need an external power source - I think that's what you mean

To do this you can use for example a typical laptop type hard drive (2.5 inch) max 1 TB and mount in an external enclosure -- most computer stores sell a "PATA=> USB" drive type of enclosure case for around 10 - 20 USD.

Quite frankly it's cheaper to buy something like a WD "Usb Passport" 1 TB drive for around 55 USD -- then you've got both Disk and drive doing what you want WITHOUT the need for an external power source.

At the present time I don't think you'll find a larger capacity than 1 TB which will work without an external power source.

Cheers
jimbo

Have a look at this:
You could build own ext HD.
Build your own External Hard Drive

Thanks for your responses....