No Partition after trying to format a USB External Drive

[Bushpig]

Hi Guys,
I am a newbie to this and need help please. I have been given a Seagate 1TB USB External drive that suddenly ended up RAW. The old owner tried to format the drive using windows, without success. Data recovery is not required. After running TestDisk the following appears;
TestDisk 7.0, Data Recovery Utility, April 2015
Christophe GRENIER <grenier@cgsecurity.org>
http://www.cgsecurity.org

Drive Z: - 1000 GB / 931 GiB - CHS 121601 255 63
Current partition structure:
Partition Start End Size in sectors

P Unknown 0 0 1 121600 254 63 1953520065

>[Quick Search]
Try to locate partition

After running Quick Search the following appears;

TestDisk 7.0, Data Recovery Utility, April 2015
Christophe GRENIER <grenier@cgsecurity.org>
http://www.cgsecurity.org

Drive Z: - 1000 GB / 931 GiB - CHS 121601 255 63
Analyse cylinder 1/121600: 00%
Read error at 0/254/63 (lba=16064)

Stop

Can I do anything from here to get the drive working?

[Fiona]

Often I've solved format issues of large disks using an external USB Hub with power supply.
Can you test it?

Fiona

[Bushpig]

Hi Fiona,

This Drive is a Seagate Expansion Drive p/n 9sf2a4-500 USB and has it's own power supply.

[Bushpig]

I assume that Fiona's previous comment suggests that the usb drive may not have enough power to operate correctly. The drive has its own power supply and I have also tested it with another power supply with the same outcome.
I do apologize for making a basic mistake. I have been checking a drive not a disk.
When using Testdisk in Analyze, there are read errors at every cylinder.
Following a deeper analysis of the disk it still shows no partition found.
I have tried Crystaldiskinfo with no success as the drive is not SMART.

Where to go from here is the next question?