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[Tyler Schnuckel]

I'm putting together a RF rig of Shure ULX's. They are connected to a UA844 (distro) housed in a rack case. Most of the time they will be used in doors at a FOH position about 80-90ft from the stage. If the case is placed on a table the antennas will be slightly above audience head height.  There might be chance that the rack would go on the floor, so obviously the antennas would need to be mounted on stands then. The front of the case faces away from the stage.

1) Put 1/2 wave omni antennas on the rackears?
2) 1/2 wave omni antennas on stands clearly above heads (like at 6ft). I wouldn't use an amplifier since the RG58 would be <25ft?
3) Use directional antennas (flag/batwing)?

[Thomas Lamb]

I'm putting together a RF rig of Shure ULX's. They are connected to a UA844 (distro) housed in a rack case. Most of the time they will be used in doors at a FOH position about 80-90ft from the stage. If the case is placed on a table the antennas will be slightly above audience head height.  There might be chance that the rack would go on the floor, so obviously the antennas would need to be mounted on stands then. The front of the case faces away from the stage.

1) Put 1/2 wave omni antennas on the rackears?
2) 1/2 wave omni antennas on stands clearly above heads (like at 6ft). I wouldn't use an amplifier since the RG58 would be <25ft?
3) Use directional antennas (flag/batwing)?

I have had good luck with ULX using them in many ways that is not optimal. However, using your list I would probably go 3,1,2. If you have higher gain directional antenna that will always be better from FOH IMHO. And the reason for 1 over 3 is unless you have some sort of ground plane for the omnis mounted on stands they will not work well. I learned this the hard way earlier in life. I still don't fully understand what having the ground plane does but completely understand that it does something.

T

[Curtis Sumter]

I'm putting together a RF rig of Shure ULX's. They are connected to a UA844 (distro) housed in a rack case. Most of the time they will be used in doors at a FOH position about 80-90ft from the stage. If the case is placed on a table the antennas will be slightly above audience head height.  There might be chance that the rack would go on the floor, so obviously the antennas would need to be mounted on stands then. The front of the case faces away from the stage.

1) Put 1/2 wave omni antennas on the rackears?
2) 1/2 wave omni antennas on stands clearly above heads (like at 6ft). I wouldn't use an amplifier since the RG58 would be <25ft?
3) Use directional antennas (flag/batwing)?

Could you place the receivers and antennas on or near the stage and plug them into your snake? Once you have the system setup, I don't see a big need to have the receivers at your FOH position. Maybe set them to the side of the stage so you can get to them if something needed to be changed or fixed. Although I don't have a big wireless setup, I've never had to make any adjustments to my system after a sound check in over 16 years of using wireless systems. If you have to setup the antennas near your FOH position, I would consider using the directional antennas. I believe that the Shure directional antennas have a built in amplifier so could setup the antennas on stands for a better line of sight to the stage or down from the ceiling if that would work in your situation.

[Jerome Malsack]

from Wikapidia

The radio waves from an antenna element that reflect off a ground plane appear to come from a mirror image of the antenna located on the other side of the ground plane. In a monopole antenna, the radiation pattern of the monopole plus the virtual "image antenna" make it appear as a two element center-fed dipole antenna. So a monopole mounted over an ideal ground plane has a radiation pattern identical to a dipole antenna. The feedline from the transmitter or receiver is connected between the bottom end of the monopole element and the ground plane. The ground plane must have good conductivity; any resistance in the ground plane is in series with the antenna, and serves to dissipate power from the transmitter.

I would recommend the directional antenna pointed to the stage placed on a stand as high as you can get it. 

Computer and digital systems can cause lots of RF noise.  Keeping the antenna away from the sources helps. 

Using a low loss cable over the RG58 would help. 
going up a cable size to RG8 would help. 

There is a formula to calculate signal loss in cable.  calculate for your frequency and cable.  I use half the cable only for my VHF.  This ensures I dont loose signal in the cable. 

You can visit a library and read some from ARRL. 
Amateur Ham Radio browse internet. 

http://www.hamuniverse.com/coaxdata.html
Get to now a ham or the club and you can find some support.

[Scott Helmke]

First recommendation would be to use directional ("paddle") antennas, option #3. 

As far as the half-wave omni antennas go, the usual ones that Shure includes with ULX and better are center-fed dipoles.  So they don't need a ground plane and would work fine up on mic stands.

[Pete Erskine]

Most of the time they will be used in doors at a FOH position about 80-90ft from the stage.

3) Use directional antennas (flag/batwing)?

I always use Flat/paddles.  Gain in one direction always helps.

Also there is no advantage to putting your RX at FOH to cover the stage.  Put your RX at the stage.  Just because it's wireless don't think it is OK to RX far away.  Even if you need to run long antenna cables the loss through the air will be greater than the loss through good antenna cable like LMR-400.

Do not underestimate the absorptive effect of people.  Line of sight is imperative to good RF RX.

[Jordan Wolf]

Tyler,

I agree with the others.  Use directional paddles on mic stands and locate the receiver near the stage.  If you need to, you can network the receivers and use WirelessWorkbench to check battery and RF status, etc.  All it takes is a run of CatX cable, a network switch, and some setup.

[ProSoundWeb Community]