I have a newsletter that I make available in pdf form (searchable pdf) on my site.

I also would like to make the same content available on a blog, in a subdomain (/blog) of the same site.

But, I don't want to get hit with a duplicate content penalty for duplicate content on the same site. This is similar to the situation where there is a an article on a web page, plus a separate page on the same site with the article in "print ready" format.

I have heard that HTML pages have better SEO value than PDF documents.

What should I do?
- Delete the pdf's from my site?
- Put the pdf's in a subdirectory, and do a robots exclusion on the subdirectory?
- Put the pdf's in a password protected subdirectory?
- Tag the pdf's as noindex? (Google's duplicate content guidelines suggest this, but I don't know how to do it for a pdf.)

Would appreciate any suggestions, thanks.