How to increase tuning rang of Ring type ILFD

[haideruet]

HI,
I am using ring-ILFD , now I have to improve the tuning range of this circuit.
So, which parameters affect the tuning range.
thanks

 

[erikl]

The quality factor (Q) of the oscillator tank, s. here (scroll down to ILFD).

 

[haideruet]

The quality factor (Q) of the oscillator tank, s. here (scroll down to ILFD).

Thanks for help but my ILFD is Ring type it does not have Tank ckt, instead each cell has trans and Resistor.