Hi All.
I have a circuit of a 2m rx front end which works well, the output is fed
into a 9mhz if stage.
What i would like, is to be able to have this circuit modified to work in the
4m(70Mhz) and 6m(50Mhz) bands, I know that some components will have
to be changed and i have marked the parts with a * .
The front end coils in the 2m one are from Coilcraft (146-04J08SL), i also
have these coils from them:
2x 146-06J08SL 6.5t
2x 146-07J08SL 7.5t
2x 146-08J08SL 8.5t
2x 146-10J08SL 10.5t
Do you mean for NewCap, divide 145.000Mhz(OldFreq) by 70.000Mhz(NewFreq) = 2.0714285
then multiply OldCap(3.3pF) by 2.0714285 = NewCap(6.835714) or 6.8pF.
Do you mean for NewInd, divide 70.000Mhz(NewFreq) by 145.000Mhz(OldFreq) = 0.4827586
then multiply OldInd(.146uH) by 0.4827586 = NewInd(.0704827) or .071uH