The units I have seen appear to have a 1/2 wavelength of cable. The loops are typically 1/8 wavelength equivalent and with 2 loops and the cable will equal 3/4 wavelength. I have also seen some of the old (rounded top) Sinclair cans with side connectors joined together with only a double female adaptor which would be equal to 1/4 wavelength connection.
The cable length is not super critical. Burt VE2BMQ n...@no6b.com wrote: > At 4/19/2010 10:24, you wrote: > > >> I have 2 C-Series bandpass cavities, with individual I.L. set at 1.0 db >> each. When I couple them together and measure, I get a total I.L. of 2.9 >> db. I should see something like 2.1 or 2.2. I have measured the coupling >> cable and see< .1 db, so the cable is good. Anyone have an idea why the >> loss is so high when coupled? > > Did you actually measure the individual loss of each can, or are you just > going by the indicators on the loops? > > Try changing the length of cable between the cans. I think an electrical > 1/4 wave multiple (1/4, 3/4, 5/4, etc.) is what you want. > > Bob NO6B > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > >