Design of a Bias Tee for measuring varactor diode impedence

[shopi Ram]

Hai,

I need to design a bias Tee for measuring the capacitance of varactor diode using VNA.
To bias the varactor diode i need dc.To measure the capacitance i use S11 value from the VNA. So to separate the RF and DC i need a bias tee arrangment.
So pls suggest some design techniques/link/books for designing a wide band bias tee (Range 300K to 5G Hz)

Thanks

 

[fishbrook02]

many vna's have a bias tee built in.

https://www.edaboard.com/threads/54929/

 

[shopi Ram]

Hai,

That was useful. But actually i am intrested in designing a bias tee .I am completely new to it. So pls suggest me design procedures /Links .That would really be useful.

Thanks
Shopitham.

 

[fishbrook02]

You can start here

https://www.edaboard.com/threads/135389/

 

[shopi Ram]

Hai,

I read through "VNA measurement" I checked the resistance btw the port terminal and gnd ,the meter read a resistance much higher than 50 ohms. Also near my VNA port iti read this "30 VDC 28 dbm" does that mean there is a bias tee inside my network analyzer. Will the VNA gnd the DC ?