Core: evaluate unknown core

created@2014 6/25

every ham, might have many core, some of them you don't know the parameters of the core. if the core suitable for choke/transformer or filter? 

Does my core suitable for RF choke @2014/6/25

first time i encounter the core failure because unsuitable for use as RFC in  RF choke: dig SRF project. for long time i want to find some way to identify a un-known core's capability.  

this experience given me hint to evaluate if the core is suitable for choke, just built a oscillator like this one to to check it.