The question was a band pass filter between a receiver and a duplexer. First thing Lloyd said was lengths between cavities and the output TEE, comprising a duplexer are extremely critical. The original post cited a working system with interference, hence a band pass filter between the receiver and the duplexer, followed by questions concerning cable lengths between the receiver and in line filter, and the inline filter and the duplexer receive port. The supposition being receiver overload in the ham repeater coming from the 155? Mhz public safety system. Often a BPBR cavity may not reject signals 5 to 10 mhz from the pass frequency but do a splendid job of rejecting signals 600 khz from the pass frequency.
Your pdf is excellent and very well done. Thanks for the great presentation Jeff. Best regards, Steve NU5D Jeff DePolo wrote: >> According to Lloyd, the cable length between a duplexer and >> an inline >> cavity filter and the receiver makes little or no difference. >> > > Steve, > > Was the question posed (or probably misunderstood as being) whether the > cable length between the receiver and the filter being critical, or the > cables between filter sections being critical? If the latter, then I would > have to humbly disagree with the answer, as theory and personal experience, > as well as the results of the test earlier today, has been to the contrary. > > --- Jeff > > > > > >
