#### chiques

##### Full Member level 3

- Joined
- Nov 21, 2007

- Messages
- 168

- Helped
- 2

- Reputation
- 4

- Reaction score
- 2

- Trophy points
- 1,298

- Location
- California

- Activity points
- 2,534

https://www.coilcraft.com/getmedia/8ef1bd18-d092-40e8-a3c8-929bec6adfc9/doc363_measuringsrf.pdf

But when I follow this simulated circuit shown on https://www.microwaves101.com/encyclopedias/self-resonant-frequency , the equation is the following for an inductor.

I see they mentioned they added a factor of 1000 so the equation works out. What I don’t understand is why the equation is way off from the SRF version.

Note: The Microwaves simulation in my simulator is close but still off. I get 1.7GHz SRF where they get 2.3GHz.

When I try to correct the simulation to

I get:

Anyone have any idea what I’m missing here?