Hi!
My apologies – I thought I'd attached piccies to my query but it looks like they went walkabouts!
I'll retake the pictures and add them to my post!
Chris Williams
If it looks like the in the picture posted by tropicalSpeed then it's one of the Belden, Volex & Alpha round pin power cords with the oval PH163 connector, these turn up regularly on ebay in the US both new & used, it seems they were also used on some audio equipment too.
I did see some in Germany but can't find them now (probably just as expensive as the ones in the USA).
Also Sphere have new ones at this page, scroll down the page to find them:
http://www.sphere.bc.ca/test/hp1.htmlI bought a couple from them a few years ago.
I know the polarity of the live & neutral pins is reversed on the cables used for HP equipment, not sure about other test equipment brands, information on the second page of the attached pdf.
David