I didn't want to overwhelm the gentleman. wa9zzu
--- On Mon, 5/31/10, Richard W. Solomon <w1...@earthlink.net> wrote: > From: Richard W. Solomon <w1...@earthlink.net> > Subject: Re: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning > a DB Products Duplexer > To: Repeater-Builder@yahoogroups.com > Date: Monday, May 31, 2010, 8:09 PM > > > > > > > > > > > > > > > > > > > > > > > > > > You forgot the most important text: > > > > Microwave Spectroscopy by Townes & Shalow. > > > > 73, Dick, W1KSZ > > > > -----Original Message----- > > >From: allan crites <wa9...@arrl.net> > > >Sent: May 31, 2010 8:38 PM > > >To: Repeater-Builder@yahoogroups.com > > >Subject: Re: [Repeater-Builder] Re: Help Needed > (Guidance and advice) tuning a DB Products Duplexer > > > > > >Kuby, > > > > > > You might start with "Electronic and Radio > Engineering" by Frederick Emmons Terman, 4th Ed. 1955 > in the Circuit Elements and Circuit Theory section. > > > > > >And try "Radio Engineering Handbook" by Keith > Henny, 5th Ed. 1959 in Chapter 6, Wave Guides and > Resonators by Harald Schutz. > > > > > >Also "Principals of Radar" 3rd Ed. 1952 by J. > Francis Reintjes and Godfrey T. Coate in ch.9, Resonant > Lines and Cavities. > > > > > >And "Microwave Transmission Design Data" by > Theodore Moreno, 1948, ch. 13 > > >Cavity Resonators. > > > > > >Then when you finish with these publications you will > have all the answers to all your questions and then some. > > > > > >WA9ZZU > > > > > > > > > > > >--- On Mon, 5/31/10, Kuby <n6...@yahoo.com> > wrote: > > > > > >> From: Kuby <n6...@yahoo.com> > > >> Subject: [Repeater-Builder] Re: Help Needed > (Guidance and advice) tuning a DB Products Duplexer > > >> To: Repeater-Builder@yahoogroups.com > > >> Date: Monday, May 31, 2010, 1:22 PM > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> Anyone have white papers or info on how to > > >> modify/design cavities? > > >> > > >> > > >> > > >> What would it take to move a window 465 can to > 445/435 > > >> tunable? > > >> > > >> What is the design parameters for the N connector > straps? > > >> > > >> What is the design of existing tunable cans (L/C > > >> components)? > > >> > > >> > > >> > > >> --- In Repeater-Builder@yahoogroups.com, > > >> "Eric Lemmon" <wb6...@...> wrote: > > >> > > >> > > > >> > > >> > Not really. I had not seen this in any of my > older > > >> catalogs, and I wondered > > >> > > >> > if in fact the unit was made by Decibel > Products. > > >> Like many RF products, > > >> > > >> > ferrite isolators in particular, the > frequency range > > >> stated in a > > >> > > >> > manufacturer's catalog refers to the > capability to > > >> construct- which is not > > >> > > >> > the same as the field-tunable range of a > specific > > >> product. I was curious if > > >> > > >> > the window filter (AKA preselector) could be > useful in > > >> the 70 cm Amateur > > >> > > >> > band without modifying the coupling loops or > jumper > > >> cables. > > >> > > >> > > > >> > > >> > 73, Eric Lemmon WB6FLY > > >> > > >> > > > >> > > >> > > > >> > > >> > -----Original Message----- > > >> > > >> > From: Repeater-Builder@yahoogroups.com > > >> > > >> > [mailto:repeater-buil...@yahoogroups.com] > > >> On Behalf Of Jeff DePolo > > >> > > >> > Sent: Monday, May 31, 2010 6:09 AM > > >> > > >> > To: Repeater-Builder@yahoogroups.com > > >> > > >> > Subject: RE: [Repeater-Builder] Re: Help > Needed > > >> (Guidance and advice) tuning > > >> > > >> > a DB Products Duplexer > > >> > > >> > > > >> > > >> > > > >> > > >> > > > >> > > >> > > > >> > > >> > Mine don't have labels on them. Usually > they were > > >> sold as part of an SP > > >> > > >> > package that included the window filters, > > >> multicoupler, etc. > > >> > > >> > > > >> > > >> > I haven't tuned or swept this particular > set, but > > >> from experience, the > > >> > > >> > cavity resonance will tune over a wide swath, > probably > > >> the full 406-512 MHz, > > >> > > >> > but the loop lengths may not be optimal over > such a > > >> wide span (depending on > > >> > > >> > how the cavities are being used), and > likewise, the > > >> cable lengths will vary. > > >> > > >> > > > >> > > >> > You have something in particular in mind you > want me > > >> to test? > > >> > > >> > > > >> > > >> > --- Jeff WN3A > > >> > > >> > > > >> > > >> > > -----Original Message----- > > >> > > >> > > From: Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > [mailto:Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> ] On > > >> Behalf Of Eric Lemmon > > >> > > >> > > Sent: Sunday, May 30, 2010 12:29 PM > > >> > > >> > > To: Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > Subject: RE: [Repeater-Builder] Re: Help > Needed > > >> (Guidance and > > >> > > >> > > advice) tuning a DB Products Duplexer > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > Jeff, > > >> > > >> > > > > >> > > >> > > Can you positively identify the window > filters by > > >> part > > >> > > >> > > number? Also, what > > >> > > >> > > is the useful frequency range of the > units you > > >> purchased? > > >> > > >> > > > > >> > > >> > > 73, Eric Lemmon WB6FLY > > >> > > >> > > > > >> > > >> > > -----Original Message----- > > >> > > >> > > From: Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > >> > > [mailto:Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> ] On Behalf Of Jeff DePolo > > >> > > >> > > Sent: Sunday, May 30, 2010 8:39 AM > > >> > > >> > > To: Repeater-Builder@yahoogroups.com > > >> > > >> > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > > <mailto:Repeater-Builder%40yahoogroups.com> > > >> > > >> > > >> > > Subject: RE: [Repeater-Builder] Re: Help > Needed > > >> (Guidance and > > >> > > >> > > advice) tuning > > >> > > >> > > a DB Products Duplexer > > >> > > >> > > > > >> > > >> > > <snip> > > >> > > >> > > > > >> > > >> > > I bought two sets of those window > filters from > > >> the same guy, > > >> > > >> > > but I knew what > > >> > > >> > > they were, caveat emptor is the golden > rule at > > >> Dayton or any > > >> > > >> > > other hamfest. > > >> > > >> > > Actually I think I gave him $75 for the > pair, and > > >> I took the two > > >> > > >> > > cleanest/newest ones he had (the newer > dark-tan > > >> ones). > > >> > > >> > > > > >> > > >> > > --- Jeff WN3A > > >> > > >> > > > > >> > > >> > > <snip> > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > > > >> > > >> > > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > > > > > > > >------------------------------------ > > > > > > > > > > > >Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
