Re: 900MHz Duplexer The black stubs look like generic 2 way 50 ohm power divider - combiner assemblies... although the heat sink look might throw you off a at first glance.
Sometimes paging transmitters are set up to be frequency agile... This filter assembly appears to be set up as two parallel band pass filter assemblies for a frequency agile paging transmitter. The cavities should make a decent 900 MHz duplexer if you have the proper coax probe ports and cables configured, which is not a super easy task but quite doable. Better to reconfigure it as a BpBr duplexer or this would make a fairly neat transmit combiner. cheers, s. > "georgiaskywarn" <[EMAIL PROTECTED]> wrote: > > You may be right Jeff...it is a load of sorts. One piece but 3 ports. > You would think by taking out the transmitter "load" (or what ever it > is) you might could use one side for the rx and one side for the tx. > I guess cabling would have to be reconfigured. Shame. Nice loops. > > Don't know. But someone could have this for a steal. Especially if > your going to the ATL hamfest this weekend ;-) > > Robert > KD4YDC > > > > --- In Repeater-Builder@yahoogroups.com, "Jeff DePolo" <jd0@> wrote: > > > > > Can these 900mhz dup.s be used on 900mhz VOICE repeater? They were on > > > a paging system and are Bp dup.s. > > > > Without measuring the rejection at whatever offset (12 MHz, 25 MHz, > etc.) > > they would be used at, it's hard to say whether or not two pass > cavities on > > each side would afford enough isolation. The orientation of the > coupling > > loops will obviously play a roll in determing rejection and > insertion loss. > > > > That black "thing" where the tee is - it has "fins" that make it > look like a > > reject load? Seems strange. Or is it just a standoff to support > the tee? > > I have some other big Wacom cavities like that which were part of a > > combiner, but the standoffs for the tees and star junctions were > just metal > > posts, they don't like anything like that black gizmo. Curious. > > > > How much are they worth? Depends on who's buying them :-) > > > > --- Jeff WN3A > > >
