Eduardo I have a example of the RC circuit just like in the file you linked to on the SSB circuit in the 196 "URE" publication. I will model some circuits with this. What I like about it is that it looks like it can be very wide banded. Being it is not a resonant circuit. Though it does recommend that C1 be selected according to the band of operation.
The rest of the circuit in the PDF file looks very interesting. I might use that in something. I will look into these RC 90 degree phasing circuits and see what they can do in wide band applications. I think they might work over a wide bandwidth, it would be nice. If so, then that will help out in HF home brew projects. I uploaded some more models in the folder at the group. I have some rf op amp circuits in some of my new models. Dan
