ZX Spectrum 48K - How to replace the ROM with an EPROM

How to replace the ZX Spectrum (48K version) ROM with an EPROM, and having available two different ROMs to boot from.

References:-
http://www.retroleum.co.uk/electronics-articles/how-to-replace-the-rom-of-a-zx-spectrum-with-an-eprom/
http://www.retroisle.com/sinclair/zxspectrum/Technical/Hardware/ZXSpectrumIssue3-Schematics.gif

More details of the project over at my website - http://www.ianjohnston.com/index.php/videos/5-video-blog-016-how-to-replace-the-zx-spectrum-48k-version-rom-with-an-eprom

And here's some info on how to edit live Spectrum BASIC files on a PC - http://www.ianjohnston.com/index.php?option=com_content&view=article&id=104

Видео ZX Spectrum 48K - How to replace the ROM with an EPROM канала IanScottJohnston