Wireless 1/2 Wave Antenna mounting orientation ?

[rsmith]

Hi folks,

For years I have had my wireless receivers in portable road cases and always had good luck with simply using the 1/4 wave antennas on the back of the receivers. I always used to orient the A & B antennas 45 degrees opposite of each other (I can't remember where or when, but I thought I read years ago to set them up that way!).

I am now installing a new set of 12 SLX units that will stay in the auditorium pemantetly, I thought since I have more units with obviously more distribution amplifiers, etc, that I would remote mount a couple of 1/2 wave antennas (UA820's). The simple instructions from Shure show a straight up vertical picture, nothing about 45 degree angles, etc.

I would just like to confirm with anyone using Shures with 1/2 Wave antennas that vertical (or even horizontal ??) orientation is fine.

-thanks
-Ray

 

[abartucci]

When I use antennas, I always have one straight up and one at a 45 degree angle.

Have you looked into the shark fin antennas (Shure UA870) ? 12 channels of wireless is a lot to be asking of 1/2 waves in my opinion.

 

[Chris15]

You will get the best performance from an RF system when the trasmitting and receiving antennas are aligned in the same plane.
When dealing with TV antennas on the roof - easy.
We on the other hand have to contend with the fact that transmitter antennas will change orientation frequently and normally while transmitting.

Having a verticallly polarised transmit and a horizontally polarised receive will result in a 20dB loss...
So 45 degrees sits in the middle of those two reasonably well.
45 also helps reduce the coupling between antennas when mounted in close proximity to one another.

Refer also to Shure's Knowledgebase article here: Remote Antennas for UHF-R, UHF, UC, SLX or ULX Wireless Microphones

 

[FMEng]

Most of the time, antennas are tilted at 45 degrees. This is done because most of metal in a building structure is either vertical or horizonal. The antenna at 45 degrees is less likely to negatively interact with the building's materials. Maximum benefit from the diversity pair can be had by placing the antenna at 90 degrees to each other by tilting one 45 degrees one way and the other 45 degrees the other way. That way, one antenna is at maximum while the other antenna is at minimum null.

Even though Shure doesn't address polarization in their tutorial, notice how the antennas are splayed in their picture.

 

[howlingwolf487]

Maximum benefit from the diversity pair can be had by placing the antenna at 90 degrees to each other by tilting one 45 degrees one way and the other 45 degrees the other way. That way, one antenna is at maximum while the other antenna is at minimum null.

+1

I think that sums it up nicely.

 

[rsmith]

ok, thanks - I'll stay with the opposite 45 degree orientation set up.
-Ray

 

[mbenonis]

Most of the time, antennas are tilted at 45 degrees. This is done because most of metal in a building structure is either vertical or horizonal. The antenna at 45 degrees is less likely to negatively interact with the building's materials. Maximum benefit from the diversity pair can be had by placing the antenna at 90 degrees to each other by tilting one 45 degrees one way and the other 45 degrees the other way. That way, one antenna is at maximum while the other antenna is at minimum null.

Even though Shure doesn't address polarization in their tutorial, notice how the antennas are splayed in their picture.

Yep, that's what I do. The farther apart you can get the antennas as well, the better.

 

[DaveySimps]

I have a set up of 16 SLX wireless systems with 1/2 waves just like you mention. I always have mine at 45 degrees. We always get great reception at 65' away where the receivers are housed.

~Dave