Late last year Pete (N4ZR) reported problems with his home brew Bias Tee
that included radical shifts in measured impedance when DC voltage was
applied to his Bias Tee. Today I decided to make impedance measurements on
a simple Bias Tee circuit I recently proposed for Dwight (NS9I) who was
We cannot test impedance that way with a DC coupled impedance meter and get
good data with any noise in the supply. Any test is meaningless. The .1
capacitor will just couple any distortion or ripple in the AC to the
analyzer, where it would show as jitter or false readings.
It would be a
