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http://en.wikipedia.org/wiki/Code_page_1252

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http://en.wikipedia.org/wiki/Code_page_1251

The Ф can be found at position D6, not E6 in codepage 1251. At position D6 in codepage 1252, you will see an ?ñ. So, the Ф will appear in a machine configured for a western font as ?ñ, not f, there exists no automatic transliteration.