Hi Bob, It is simple really - all of the common gadgets sold for ham use as duplexers are really diplexers that can be used as duplexers or diplexers :)
And Dom is correct. The microwave Radars used a similar principle but with 1/4 wave sections of waveguide instead of coax. The gas tubes would short the waveguides when the transmitter was on making the other end a high impedance and disconnecting the receiver. 73, Tony AA2TX --- At 04:56 PM 4/9/2011, Bob- W7LRD wrote: > I'm really trying to "absorb" all this diplexers/duplexor > thread. Specifically I have a new FT-8800 and want to run FM sats > from my truck. Not wanting to reinvent the wheel would a simple > dual band whip suffice. Then maybe requiring a preamp, and how all > that works maybe with a di/du etc. My head is starting to hurt. > >73 Bob W7LRD >----- Original Message ----- >From: "Andrew Rich" <[email protected]> >To: [email protected], "i8cvs" <[email protected]>, "Amsat - BBs" ><[email protected]>, "Anthony Monteiro" <[email protected]> >Sent: Saturday, April 9, 2011 1:39:01 PM >Subject: [amsat-bb] Re: Diplexer > >DU = TX RX >DI = RX >----- Original Message ----- >From: "Art McBride" <[email protected]> >To: "'i8cvs'" <[email protected]>; "'Amsat - BBs'" <[email protected]>; >"'Anthony Monteiro'" <[email protected]> >Sent: Sunday, April 10, 2011 6:27 AM >Subject: [amsat-bb] Re: Diplexer > > > > As I understand it, > > A Duplexer allows for transmission and reception to take place in the same > > band using a single band antenna. > > A Diplexer allows for transmission and reception to take place on > > different > > bands using a multi-band antenna. > > > > Art, > > KC6UQH > > > > -----Original Message----- > > From: [email protected] [mailto:[email protected]] On > > Behalf Of i8cvs > > Sent: Saturday, April 09, 2011 10:35 AM > > To: Amsat - BBs; Anthony Monteiro > > Subject: [amsat-bb] Re: Diplexer > > > > ----- Original Message ----- > > From: "Anthony Monteiro" <[email protected]> > > To: <[email protected]> > > Sent: Saturday, April 09, 2011 5:15 PM > > Subject: [amsat-bb] Re: Diplexer > > > >> A "duplexor" is a device that allows both transmitting and > >> receiving over the same transmission line or antenna. It > >> may or may not be a passive device and it may or may not > >> be frequency selective. > >> > >> In WWII RADAR systems, a duplexor was used to allow > >> the transmitter and receiver on the same frequency to > >> share the same antenna. The duplexor was a waveguide > >> device that had special gas-filled tubes to quickly > >> switch the signal direction. > >> > >> 73, > >> Tony AA2TX > >> > > Hi Tony, AA2TX > > > > I have in my hands the Instruction Book for Radar Recognition > > Sets AN/UPX-6 of U.S. Navy Department Bureau of Ships. > > > > The UPX6 is a IFF transponder on board of aicrafts and was used > > in WWII for Identification of Friend or Foe. > > > > The UPX-6 can transmit from 1010-1030 MHz and receive from > > 1090-1110 MHz and allows both transmitting and receiving over > > the same transmission line and antenna via a circuit made of coax > > cable RG-58/CU that the manual calls a "DUPLEXER" and not > > a "duplexor". > > > > This "duplexer" is working on the fact that a transmission line, > > shorted at the far end a quarter wavelenght long for the incoming > > signal,represent infinite impedance (an open circuit) at the sending > > end of the line. > > > > The UPX-6 was converted in the early 1980's to be used on 1296 MHz > > and an interesting article written by W6NBI was published in Ham > > Radio Magazine march 1981 > > > > I modified it and I got 40 watt output.......not too bad for that epoch > > time ! > > > > Best 73" de > > > > i8CVS Domenico > > _______________________________________________ > > Sent via [email protected]. Opinions expressed are those of the author. > > Not an AMSAT-NA member? Join now to support the amateur satellite program! > > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > > > __________ Information from ESET NOD32 Antivirus, version of virus > > signature > > database 6027 (20110408) __________ > > > > The message was checked by ESET NOD32 Antivirus. > > > > http://www.eset.com > > > > > > > > > > __________ Information from ESET NOD32 Antivirus, version of virus > > signature > > database 6029 (20110409) __________ > > > > The message was checked by ESET NOD32 Antivirus. > > > > http://www.eset.com > > > > > > _______________________________________________ > > Sent via [email protected]. Opinions expressed are those of the author. > > Not an AMSAT-NA member? Join now to support the amateur satellite program! > > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > >_______________________________________________ >Sent via [email protected]. Opinions expressed are those of the author. >Not an AMSAT-NA member? Join now to support the amateur satellite program! >Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
