Phil,
I did a little digging and found this:
Re: Audio isolation transformer question
From: Philip Atchley <ko6bb1@...>
Date: Thu, 01 Mar 2018 11:15:15 EST
Hi,
I've used Triad SP-67 600:600 Ohm transformers with great success. Not cheap, but good quality, compact, and they seem to be well matched as images etc are nearly non-existent.
NOTE: I have my HRD set up to display 192KCs of bandwidth, there is a very narrow "notch" right on the LO frequency. That is determined by the low frequency cutoff of the transformer, but it also prevents the sharp "spike" that you may otherwise see at the LO frequency.
Think I got mine from Mouser Electronics.
73 From "The Beaconeer's Lair"
I hope this helps.
73,
Patrick KF4LMZ
