They might be useful in the range 20-200kHz with 50 ohm, see the notes
on http://www.noding.com/pictures/la8ak/n12.htm where it is some notes
to describe inductance requirements for toroid transformers
(all text is not written, tried to use word, but it was a disaster, so
I have to wait and look for another html editor to finish the page)

Many of us have already confirmed that pulse transformers may work
perfectly well in linear circuits, so I wonder if the comments that
they shouldn't is only based on lack of practical experience, any
ferrite transformers may even be used as memory for old type computers

73
Jan-Martin

On Sat, 15 May 2004 16:38:46 -0400, Ken Scharf
wrote:

I discovered a lot of pulse transformers. They appear to have primary
and secondary inductance of about 1.5mh and a ratio of 1:1ct

I wonder if they could be used as broadband rf transformers
to make homebrew diode ring mixers?