a good inductance

It should have a published data sheet value. If it is one you make, keep it air all over with the stiffness of the wire to hold its shape. Use wire with lots of surface area (large diameter wire) and have the spacing between turns about the wire diameter to keep the parasitic capacitance down.

dear sir:

We always talk about the Murata inductance is good.
OK.....
How do we know the inductance is good or no good???
what parameters of inductance are the most important for a inductance ??

Hi ,

The most important parameters of an inductor are:
-inductance (measured at a certain frequency)
-Q
-SRF (self resonant frequency)

Also there are some more: tolerance, DCR (direct current resistance), etc

Serch the forum for the book :RF circuit design / by Chris Bowick in chapter 1 you will find some explanations about inductors. Also you could read the following apps from Coilcraft:

hxxp://www.aade.com/lcm2binst/coilcraft%20L%20measurement.pdf

hxxp://www.eetkorea.com/ARTICLES/2001AUG/2001AUG27_ICT_AN.PDF

(replace x with t)

You can decide which parameters are important for you based on your application


rgds, Al

Sorry for getting carried away and leaving out the second sentence that would have said to look for the Q and SRF values in the data sheets. The best commercially available inductors are made as I described. Coilcraft makes ones such as this.