You did a decent job on this. Some of the proportions are off a bit - use this character guide graphic, if you want to add characters, or make revisions:
Each glyph fits in a 12x8 pixel matrix, which includes the character, ascender, descender, and spacing.
More information about this alphabet: http://en.wikipedia.org/wiki/Code_page_437
This alphabet has been fonted previously by James Shields as [b]Green Screen[/b], (http://www.dafont.com/green-screen.font
), and by me, in a stylized version, as [b]FixCystNeon[/b], (http://www.dafont.com/fixcystneon.font
If you compare your version to James', you'll be able to find the errors.