Bandpass filter for uhf television 470-800MHZ

For good reception of uhf tv and digital tv, bandpass filter is a choice for avoiding another signal beside uhf tv channel signal. there are 3 type of bandpass filter that be known , Butterworth, Chebyshev and Bessel filter design.
As shown in this design ,   I am using  http://www.wa4dsy.net/filter/filterdesign.html software online design, or can also using Chebyshev design from http://www.changpuak.ch/electronics/chebyshev_bandpass.php 

Input frequency center for 470-800 MHz, 635 MHz , select bandpass filter or bandstop filter design as menu shown.

after input frequency center, bandwidth of the filter 330 mhz, and the impedance input/output 50 ohms, than select compute parts and the result of filter design will be shown as below.

Build This Digital TV Indoor Antenna 470-800 MHz

I get this idea after searching and studying literature from ARRL handbook, other sources and by experimenting several times. Although my design not perfectly design, but it shows several Channel TV in digital reception with good quality. And several of channels not in good quality. I think the future design of this antenna will give good performance for digital indoor TV antenna.

As mention in ARRL handbook, for high frequency , the equation for finding element length is :

L = 468 / Fo ( in Feet)

Where Fo = Center Frequency

If We design for 470 - 800 MHz , the center frequency will be Fo = 635 MHz, substitute to the equation :

L = 468 / 635 =  0.737 feet , convert to cm . 1 feet = 30.48 cm , so for 0.737 feet equals to :

L = 0.737 feet x 30.48 cm/feet  = 22.46 cm , this is 1/2 lambda for UHF signal in 635 MHZ.

1/4 lambda will be 11.23 cm

As I read in one of literature from S.W. Su and F.S. Chang from Lite On Technology Corporation , Taiwan and Department of Electronics Cheng Shiu University Taiwan. Wideband Rod Dipole Antenna with a modified feed for DTV Signal Reception.
From that literature we can have the design of PCB , feed gap, and dipole design.

I use experiment PCB, and cut the corresponding to the design.The result of antenna as shown .

My design not exactly the same as the design from S.W. Su , i use 1/4 lambda for both arms.