A rare working example of the world's first ever PC is expected to fetch £30,000 ($46,410) at an auction next month.

The Kenbak-1 was invented in 1970 - predating the Apple I's release by six years - and ran on a series of integrated circuits mounted onto a single circuit board.

Only 40 units were ever sold and the working model being auctioned off was the seventeenth to be produced in this single run of units.

A rare working example of the world's first ever personal computer is expected to fetch £30,000 ($46,410) at an auction next month. The Kenbak-1 (pictured) was invented in 1970 - predating the Apple I's release by six years - and ran on a series of integrated circuits mounted onto a single circuit board

Auction Team Breker, which is running the auction in association with Live Auctioneers and The-Saleroom.com, said the lot 'rewrites computer history'.

It was designed by John Blakenbaker in LA before microprocessors were available and its memory contained just 256 bytes. It was capable of executing several hundred instructions per second.

A HISTORY OF THE KENBAK-1 The Kenbak-1 was invented in 1970 - predating the Apple I's release by six years - and ran on a series of integrated circuits mounted onto a single circuit board. It was designed by John Blakenbaker in LA before microprocessors were available and its memory contained just 256 bytes. It was capable of executing several hundred instructions per second. The units went on sale a year after being invented, in 1971 for $750 (£485) each. In 1987 it was classified as the first commercially available personal computer by the Computer Museum of Boston. When Kenbak Corporation closed in 1973, a number of completed machines were sold but Mr Blankenbaker kept the prototype and two production machines, one of which was 183. Advertisement

The units went on sale a year after being invented, in 1971, for $750 (£485) each.

In 1987 it was classified as the first commercially available personal computer by the Computer Museum of Boston.

But while Apple's later PC helped the firm become a multi-billion-pound company, the Kenbak Corporation shut down in 1973.

The Kenbak-1 computer being sold has a serial number 183.

The serial numbers in the first, and only, production run of the device began at 167.

When Kenbak Corporation closed, a number of completed machines were sold but Mr Blankenbaker kept the prototype and two production machines, one of which was 183.

The other was given to the Computer Museum of Boston and later transferred to the Computer History Museum in Mountain View.

One handle had been lost on model 183, so this has been replaced, as has three integrated circuits and one transistor were replaced.

The switches on the front panel have been remounted and there are two small scratches on the top surface.

The Kenbak-1 was designed by John Blakenbaker (left) in LA before microprocessors were available and its memory contained just 256 bytes. It could execute several hundred instructions per second. The computer went on sale a year after being invented, in 1971 for $750 (£485) each (advert pictured right)

Mr Blakenbaker originally intended the Kenbak-1 (circuit board pictured) to be educational and the model being sold was demonstrated at school teacher's convention in 1971

Mr Blakenbaker originally intended the Kenbak-1 to be educational and the model being sold was demonstrated at school teacher's convention in 1971.

The auction begins at 10am CET (9am GMT) on 7 November. More details are available from the Auction Team Breker website.

In December 2014, an original Apple I computer was sold at auction for $365,000 (£230,000).

When Kenbak Corporation closed in 1973, a number of completed machines were sold but Mr Blankenbaker kept the prototype and two production machines, one of which was number 183 (pictured). The auction begins at 10am CET (9am GMT) on 7 November

It had been expected to fetch between $400,000 and $600,000 (£258,780 and £388,120) after the the Henry Ford organisation paid $905,000 (£585,420) for one of the computers two months earlier.

Yesterday auctioneers at Christie announced it was offering an Apple 1 computer for auction later this month.