New cables will be a lot more flexible, and with RG214's double shield, they should work better too. It's tempting to use the coax and TEE fitting as a handle when picking the unit up - don't do that !
I found that the connectors added exactly 1/2 inch to the cable length PER CONNECTOR, so you would want to cut the coax 1 inch shorter than the final lengths of 11-1/2 and 12 inches. I solder the center pin, rather than crimping it. Not too many analyzers will be able to go down to the 100+ dB that these duplexers are capable of providing. That's one reason why they tell you to tune each section separately. I did find that if I use my signal generator at a fixed frequency, rather than the sweeping tracking generator, I can tune the spectrum analyzer to the same frequency and crank down the filters. I can barely see the sig gen around 120dB down or more, on the final configuration. As others have mentioned, if your equipment does not provide a good 50 ohm impedance, you should use 6-12dB pads on each line connected to the section you're tuning. Of course, adding this attenuation pushes the signal even further down into the noise, but it should not be a problem on any single section. Use as much signal from the tracking generator as possible (i.e. +10dBm or more). The resulting notch from the entire duplexer will appear to be quite wide, even though the individual section notches are quite narrow. Good luck with it in the morning when it's warmer. Bob M. ====== --- tony dinkel <[EMAIL PROTECTED]> wrote: > All, thanks very much for the input. I was already > in the process of > rebuilding the interconnects to RG-214 with crimp on > RFS connectors as > a punt. That old RG-8 was hard as a rock. > > I also think my problem with the notches is that I > do not have enough > dynamic range on my ifr 1600 to see the bottom. It > works ok on the > individual cavities but once I combine the whole > circuit thats when it > mushes out. > > I think I will get this thing knocked out in the > morning. This place > is getting dark and cold. > > Thanks, > > td > wb6mie __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
