Antenna Signal Distribution

[Ocsac]

I'm planning a signal distribution setup for 20 receivers - currently a mix of SLX and EW-DX. My intent is to put two LPDA antennas overhead upstage with a 150' coax run to FOH. Coax will be selected for minimum signal loss (cost may enter into the equation at some point). If I were to use, say, the Shure UA844 for signal splitting, do I need a separate signal path for every last receiver? Do I dare consider some quality passive splitters to reduce the number of UA844s and take the 3dB hit at the split, especially if I pay attention to the coax spec for the 150' run?

 

[themuzicman]

Why overhead and why 150'? Just above head-height is usually adequate, but hey it'll probably work. I typically prefer upstage/downstage as opposed to Stage Left/Stage Right but it really comes down to what kind of sets you are performing on and the challenges of RF pickup thru the setpieces as to optimal placement

If you really can't move your receivers, something like PWS Ecoflex 10 is a super cost effective cable for long runs.

Yes, you would need an output for every receiver. I wouldn't suggest using passive splitters, consistent gain structure does help with troubleshooting when issues arise but if you are going to passive split I'd do it evenly across everything (ie buy distribution for 10 channels and split all of them out to get your 20). That being said, quality passive splitters get up there in price - the Mini-Circuits ZFSC splitters are what you see in professional RF kits and those run about $70 per split (The Shure UA221 splitter is $180 list) - by the time you've split everything and factored in patch cables you're 3/4 to the cost of doing distribution properly.

 

[macsound]

I think I understand why you want to put the antennas overhead, correct me if I'm wrong - to reduce interference from adjacent buildings?
There have been many instances where I've had to move the wireless rack from backstage to FOH or from SL to SR, just so the antennas are pointing in the opposite direction of some interference I'm encountering.

But I'd recommend doing that walk test first and identify the direction of your interference before spooling out 150' of coax, just assuming it'll be a better position.
I'd recommend RF Venue antenna distribution

 

[Ocsac]

@themuzicman: Good point on cost of the splitters. I hadn't looked closely at that.
@macsound: Yes, and the 150' is a very conservative estimate as well. There's a good chance I can keep it under 100', but I'll do some walking to look for a better solution before even committing to that.