On 2005-10-04, SH wrote:

I have two UHF (TV) arial pointing in different directions and would like to
connect them together through BP filters to minimize noise.
BP = Bandpass
Antenna 1: UHF channel (Europe) BP 1 ch 22-37, BP 2 ch40 -44, BP 3 ch 49 -
68/ or high pass
Antenna 2: UHF channel (Europe) BP 1 ch 21 / or low pass, BP 2 ch38 -39, BP
3 ch 47

It's probably more reasonable to notch out the primary interference
than to get that fancy with filtering. Eg if you have ghosts from an
interfering channel 21, notch out 21 on the offending antenna. It's
easier to make a highly selective notch than a bandpass with steep
skirts.

I have found formulas to design each section of BF but how to you connect
several BP filters in parallel???

A set of notch filters would be used in series. I believe this is
what cable companies use to control access to premium channels.

--
Ben Jackson

http://www.ben.com/