Capacitor Problem

[maffia]

Hello I have made a capacitor myself by fixing two metal rings together with air as the dielectric.

There is a strange problem, when I put a small dielectric in between the rings, theoretically the capacitance would increase since the permittivity will increase. However the capacitance actually dropped in value instead of increasing.

Does anyone know why this is happening?

Much thanks.

 

[crutschow]

What is the dielectric?

 

[shokjok]

Maffia stated that air was the dielectric. No mention if this was either a sealed or free-air capacitor.

 

[Mikebits]

Maffia stated that air was the dielectric. No mention if this was either a sealed or free-air capacitor.

No, he mentioned this.

when I put a small dielectric in between the rings, theoretically the capacitance would increase since the permittivity will increase.

Which implies he is placing a material between his plates.

 

[audioguru]

His home-made capacitor is 2pF until somebody drives past his house which decreases its measurement.

No details what so ever!