Dielectric resonator Filter at 915MHz

[moghtada]

I have a very narrow band filter at 915MHz with a 26MHz band pass. Its rejection at 930MHz is more than 30dB!!!!. I think it is a dielectric resonator filter but I am not sure about it. The photo is attached. Please help me to find the type of this filter and the part number of resonator.

Best
Vahid

 

[BigBoss]

These are Coaxial Resonators and they can be inqiured from-for instance-
http://www.trans-techinc.com/index.asp
There are other Advanced Dielectric Materials manufacturer, search google.

 

[moghtada]

Thank you a lot, real "Big Boss".

 

[biff44]

the way that board is laid out is NOT the way to do it. You want the resonator heads to all be at one side, close together. Too much line length between resonators.

Suggest u buy them from a house like this instead of making ur own...if u plan on production:
http://www.imcsd.com/products/ceramic-coaxial-resonators

You have tight specs, and every aspect of the filter assembly has to be carefully controlled to meet them.