Duplicate content?

If I set my page titles to be the same as my h1 tags,
would that be considered duplicate content by the search engines?

You should have no problem with search engines doing that.
In SEO terms duplicate content usually means full pages being the same (or one page available through several urls), having one sentence repeat itself twice on the page is perfectly fine.

thanks, I have heard that some SE give problems with sitemaps, menues, titles, h1’s being the same...
but it makes sense what you indicate...

For what it’s worth, you do have to keep abreast of Google’s ever-changing rules, but something as simple as title vs. h1, that’s so common that I don’t think Google would ever dock your SEO score for that. EVERYBODY does that.