Hi Jan, PA0SAT Your problem with VO-52 ,uplink 435 MHz and downlink 145 MHz is not due obviously by armonics but by 435 MHz overloading the IC-910 receiving 145 MHz because probably this tranceiver has a lover 1 dB compression point at 144 MHz in comparison to a FT-847 and so it is more subject to intermodulation.
Since you do not have problems using the same Maspro antennas and a FT-847 the only one to be cured is the IC-910 I suggest you to try a duplexer with the antenna connected to the common and the 2 meter port connected to the IC-910 while the 70 cm port is closed into a 50 ohm termination. The 2 meter section act as a low-pass filter and the 70 cm port as a high-pass filter while the 50 ohm termination dissipates the 435 MHz signal. 73" de i8CVS Domenico ----- Original Message ----- From: "PE0SAT | Amateur Radio" <pe0...@vgnet.nl> To: "Dimitry Borzenko" <di...@iname.com> Cc: "Amsat bb" <amsat-bb@amsat.org> Sent: Wednesday, November 21, 2012 6:03 PM Subject: [amsat-bb] Re: Who is using a IC-910 with Maspro Antennas? > Hi Dimitry, > > I know of this filter, but these are for working FO-29 when the uplink > is 145 and the downlink 435. > > The Harmonics produced by the 145 uplink signal interfere with the 435 > downlink. Now I experience the > same with VO-52 but there the uplink 435 and the donwlink 145 ??? > > So why is the 435 uplink interfering with the 145 downlink ???? > > Could this be a harmonic problem??? > > > 73 Jan PE0SAT > > On 21-11-2012 17:06, Dimitry Borzenko wrote: > > Hello Jan. > > > > Try "Desense" filter. > > More info here - http://www.amsat.org/amsat-new/articles/Mode-J/ > > > > Regards. > > > > > > -----Original Message----- > > From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] > > On > > Behalf Of PE0SAT | Amateur Radio > > Sent: Tuesday, November 20, 2012 8:12 PM > > To: Amsat bb > > Subject: [amsat-bb] Who is using a IC-910 with Maspro Antennas? > > > > Hi, > > > > Thanks for reading this message. I have exchanged my FT-847 for an > > IC-910H and now when I try to > > work VO-52 my UHF uplink signal interferes with the VHF downlink. Are > > the any people out there that > > experience the same with this combination? > > > > I tried with and without pre-amp, RHCP and LHCP but the problems > > doesn't go away :( > > > > > > I do know that there can be problems when working FO-29 and a mode-j > > filter can solve this, but I > > never experiences this when working VO-52. > > > > > > 73 Jan PE0SAT > > -- > With regards PE0SAT > Internet web-page http://www.pe0sat.vgnet.nl/ > _______________________________________________ > Sent via AMSAT-BB@amsat.org. 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 AMSAT-BB@amsat.org. 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
