If the antenna vendor and OMT vendor are the same, may not be an issue. Worst case if there is a waveguide flange, you can buy a waveguide OMT and do waveguide + remote mounts for the radios.
Thank you, Daniel White [email protected] Cell: +1 (303) 746-3590 Skype: danieldwhite Social: LinkedIn: Twitter > -----Original Message----- > From: Af [mailto:[email protected]] On Behalf Of Craig Baird > Sent: Friday, October 30, 2015 11:24 AM > To: [email protected] > Subject: Re: [AFMUG] Dish polarity question > > Interesting... this is exactly what I'm wondering... see my last post... > > Craig > > > Quoting Gino Villarini <[email protected]>: > > > But he should worry if he plans to reuse existing antennas. If the > > antenna coupling is rectangular, theses no way to inject both polarities > > into > it. > > > > On Fri, Oct 30, 2015 at 1:04 PM, Daniel White <[email protected]> > wrote: > > > >> I agree... we are saying the same things... just in different ways > >> :-) > >> > >> Many vendors now are utilizing integrated OMT's... the Ceragon IP-20S > >> uses it for instance. > >> > >> Long story short - don't worry if the BOM says Single Pol if it > >> includes an OMT. > >> > >> Thank you, > >> > >> Daniel White > >> [email protected] > >> Cell: +1 (303) 746-3590 > >> Skype: danieldwhite > >> Social: LinkedIn: Twitter > >> > >> > >> > -----Original Message----- > >> > From: Af [mailto:[email protected]] On Behalf Of > [email protected] > >> > Sent: Friday, October 30, 2015 10:41 AM > >> > To: [email protected] > >> > Subject: Re: [AFMUG] Dish polarity question > >> > > >> > I think Daniel and I are saying the same things. > >> > > >> > -----Original Message----- > >> > From: Daniel White > >> > Sent: Friday, October 30, 2015 10:13 AM > >> > To: [email protected] > >> > Subject: Re: [AFMUG] Dish polarity question > >> > > >> > This comes up all the time with many manufacturers. > >> > > >> > Almost all licensed microwave antennas a WISP is going to come in > >> > contact with have circular feedhorns, meaning their polarity is > >> > determined by the interface on the feedhorn. Typically, they are > >> > rectangular and single > >> polarity. > >> > > >> > Then an OMT is added... depending on the radio it may be an > >> > external or internal device. This combines the transmitters into a > circular feed. > >> > > >> > No voodoo required. The OMT makes a single polarity dish dual polarity. > >> > > >> > Thank you, > >> > > >> > Daniel White > >> > [email protected] > >> > Cell: +1 (303) 746-3590 > >> > Skype: danieldwhite > >> > Social: LinkedIn: Twitter > >> > > >> > > -----Original Message----- > >> > > From: Af [mailto:[email protected]] On Behalf Of Craig Baird > >> > > Sent: Friday, October 30, 2015 10:07 AM > >> > > To: [email protected] > >> > > Subject: [AFMUG] Dish polarity question > >> > > > >> > > We are getting ready to put up a licensed 11 GHz 2+0 link using > >> > > Cambium PTP820S radios. We have two 11 GHz frequencies that are > >> > > oppositely polarized for use on this path. I had assumed that we > >> > > would need to use dual polarity dishes in order to make this > >> > > work, but Cambium and our > >> > vendor > >> > > are saying that we need to use single-pol dishes. This > >> > > completely baffles > >> > me. > >> > > How can a single-pol antenna transmit in two polarities? > >> > > Cambium's answer is that it's because we're using an OMT, and > >> > > that device essentially makes > >> > the > >> > > single-pol antenna circularly polarized, so it will transmit both > >> > polarities. My > >> > > first thought is "what kind of voodoo is this?" Will this really > >> work??? > >> > I'd sure > >> > > hate to start transmitting, only to find out from an existing > >> > > license > >> > holder that > >> > > we're interfering with them because one of our frequencies is > >> > > coming out the antenna in the wrong polarity. > >> > > Can someone confirm for me that this will really fly? > >> > > > >> > > Thanks! > >> > > > >> > > Craig > >> > > >> > > >> > > >> > --- > >> > This email has been checked for viruses by Avast antivirus software. > >> > https://www.avast.com/antivirus > >> > >> > >> --- > >> This email has been checked for viruses by Avast antivirus software. > >> https://www.avast.com/antivirus > >> > >> > > > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
