uhf filter design

hi
i want to build wide band rf amplifier using mar-3 and mar-8asm for amplifing vhf and uhf signal from seprate antenna.each antenna is a yagi and have 75 ohm impedance.
any one may help me for desining input matching network?

Hello Carrrier,

Simple solution is that you have 2 bandpass filters at the input of MAR amplifier after separate antennas and after broadband amplifers combine its output with highpass and lowpass network to summing output port.
Bandpass synthesis you can do in the Ansoft AD student version with different input output impedances and output network you can do in the same CAD. When you obtain initial values than you can manualy adjust them to obtain better performances in the same CAD. If you have full version it will be very simple you can optimised values.

GL XTASA

thanks
but i don't know who to design this filters?

You may solve problem with low pass filter for VHF and high pass for UHF. Filters are both connected to input of amplifier. Download trial version of Filter Solutions at www.nuhertz.com