A transmitter may have broadband noise with considerable noise content at the receive frequency. The notch in the transmit side removes transmitter noise that may impair your receiver's capability. In an earlier post there was mention of a solid state transmitter. Traditionally tube transmitters have higher Q output circuits as opposed to wideband circuits in solid state transmitters, so a solid state transmitter may need more filtering.
There are also combination band pass / band reject duplexers and also band pass only. Each has a characteristic suited for a particular job. Beware, a duplexer may pass an intended frequency PLUS unintended frequencies outside the normal band pass. I found that 158.100 radio paging was being received by a dual band antenna, and passed right thru a 440 duplexer to cause overload in the receiver front end. In this particular instance the best solution was to go to a monoband antenna. Wishing you best success, Steve NU5D [EMAIL PROTECTED] wrote: > Thanks for the great info as soon as we get the service > monitor back we are going to try these things. > > I have already seperated the 2 sides and have seen much > improvement so I think that this is really my problem. > > I do have a question about duplexers in general. I am > sure that this is a dumb question but.... > What is the purpose of notching out the receive frequency > on the transmit side? Since I have 6 cans couldn't I move > one of the cans from the transmit side to the receive side > to give me 4 on the receive and 2 on the transmit? > > Thanks, > Vern > >
