Wireless Multiple Discrete UA844

[khazor]

I know there are many posts on here regarding use of the UA844, but I haven't seen this answered anywhere yet: What is the benefit / purpose of using daisy-chained UA844s (as recommended in the Shure user guides, and [I think] most recently discussed on this site here) as opposed to using multiple discrete UA844s, each with their own set of antennae?

The school I work for has 12 ULXS4 units, always used table-top, and always stored in their original pizzaboxes. I'm trying to convince them to rack the **** things for ease of setup/teardown and peace of mind. I know that they intend to buy 4 more in the near future. They don't always use all of them at the same time, often using either 4 or 8, depending on the size of the show/event.

I figure that the easiest way to rack these in a convenient setup would be with a few shallow 3U cases: 4 ULXS4 + 1 UA844 per case. It seems to me that each UA844 in this scenario should use its own antennae. Is there anything wrong with that? Am I missing something? Do I -have- to daisy-chain them to a master unit? Does that offer any tangible benefit? Does my proposed method create any functional hazard?

 

[Call911]

Price. With paddle antennas running about $300 each ($600 for a pair), it makes a lot more sense to buy the cheaper distro to share antennas.

Also, mounting 6 paddle antennas would look pretty funny.

Wouldn't be as bad with half-waves.

With portable racks it wouldn't be as bad. But for fixed installation it also makes sense to save on the cable going from the rack to the remote antennas.

 

[khazor]

We would be using half-waves. It's difficult to convince them to buy much of anything, so I figure that ~$30 each for half-waves would go over better with them, even buying 6 of them for this proposed setup.

I can see the argument for daisy-chaining in a fixed installation, but these get taken all over the place.

 

[gcpsoundlight]

Only thing I can see from an rf side that may be funky is if there are enough antennae near each other, it may start messing with the tuning (not frequency, but the actual front end of the receiver).

 

[Stookeybrd]

Making three kits of four with one UA844 isn't a bad idea. Using 1/4 wave antennas with each kit in close proximity to the transmitters is also fine. If you start to have large numbers of receivers for one show, it would be better to have all the kits daisy chained together, so that the receivers all see the same RF environment.

Only thing I can see from an rf side that may be funky is if there are enough antennae near each other, it may start messing with the tuning (not frequency, but the actual front end of the receiver).

Ding ding ding! It is always sad to see antenna farms at the back of a dozen stacked receivers on a table.

 

[FMEng]

Multiple antennas can be an issue due to leakage of the local oscillator via the antenna. However, since each kit of receivers will be coupled to their antennas via an active splitter, which provides very high isolation, the LO leakage cannot reach the antenna to radiate. Where multiple antennas can lead to complications is when each reciever has its own antennas.

I think the OP's idea is a good one and it should work fine.