#141 Basics of Duplexers for radio repeaters; function, alignments and tests

Excellent! Been years since I tuned a Duplexer!

Thank you so much, now I understand more about spectrum analyzers, to use tracking generator and cavity filter or duplexers. Amazing in one video you teach and share a lot of knowledge material, hope you are always healthy and blessed 🙏🏿

Great explanation of duplexors. Excellent tutorial!

Great video, explained in great detail

thank you for the informative video about the duplexer. well done.

I like your videos.Very professional and informative.Keep up the good work buddy ! Have a good day.

Very detailed video which is very helpful thanks again Peter

exellent as ever looking forward to many more..cheers peter.

Fantastic video Peter, as always!!!

Great video as always ,thank you Peter

Thanks for another great video Peter! I had a duplexer like that on my old Regency repeater. No idea what I did with it. Brought back a lot of memories with that one lol. Have a good day and take care. 73 Buddy

Congratulations! Great video explanation! much clear and pointfull!

I think it is fascinating to watch a spectrum analyzer while a filter is being adjusted, and see what each adjustment actually does to the attenuation spectrum!

Great information on the subject clear and understandble.

thank you for sharing so more information!

i hope yopu do vhf pre amp projects for repeater use, love you videos

Another great video by Peter. Excellent. Peter, can you do a video on folded dipoles for VHF or UHF base station repeater antenna.

When adjusting a duplex filter, you must connect a 50 ohm termination to the port that is open, and after adjustment you must use a SWR bridge to get the correct point where the filter has its optimal and lowest SWR still with 50 ohm termination on the open port..

Great video Peter! I have often combined these flat pack notch duplexers with additional cavity filters to help with out of band performance, essential for RF busy comms sites. One quick question, what equipment are you using for the spectrum analyser and tracking generator?

Peter, i agree with some of the other comments: The unused open port had not been terminated with a 50 Ohm load. Most, if not all duplexers need ALL the ports terminated during the tune up process as the unconnected port is still in circuit, despite not being "part" of the tune up circuit! Especially true with the small cavity multi-port duplexers that were originally designed for mobile use! Having said that, great video Peter and hope the new repeater is on air as we speak! Continue with the super work, 73, Brian EI8EJB