Re: Topband: Bias Tee Measurements (Test Data)

2014-08-23 Thread Don Kirk
Tom, you said "Any test is meaningless", and I don't understand where you are coming from on that statement. If you look at my test, I tested with and without the bias Tee, and I tested with a well regulated bench top linear power supply, and the results are similar so I don't see how you can say

Re: Topband: Bias Tee Measurements (Test Data)

2014-08-23 Thread Tom W8JI
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 vali

Topband: Bias Tee Measurements (Test Data)

2014-08-23 Thread Don Kirk
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 looking