[hpsdr] VNA interface

[FRANCIS CARCIA]

Hi All,
Phil I would think Maximo, EA1DDO has found a nice interface with plenty of isolation. I have a simple one on a single core plus a resistor that does about 25dB isolation over HF. Also I would think it a good idea to put a 3dB  or 6dB pad on the RF source port to force the source Z to 50 ohms. I built mine from the ARRL Solid State Handbook. It is a hybrid splitter which is a return loss bridge. QEX had one with 3 cores a few years ago. I had a couple emails with author on how to modify the layout to reduce lead lengths by stacking the cores. 
I could not open the link Phil provided. Frank WA1GFZ
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