Frank Mikkelsen wrote:
I whant to double a frq. between 200 and 265 MHz. I had tryed to used
the
Mini-circuits RK2 doubler and som BP filters, but because of the band
pass
200-265MHz it is diffeculd for me to suppress the input frq. and the
3*inp.
to min 50-60dB.
Is there any other ideas to realise this.

You might use a pair of MMIC's in push-push. Get gain AND cancellation of
fundamental and odd harmonics.

W4ZCB