Wireless Stadium Wireless Microphone coverage

[JJBerman]

I need some opinions on a Wireless Microphone Antenna solution for a "2 sided" outdoor high school stadium. @MNicolai I know you will have some opinions
I say "2 sided" because the press box is in the middle with 1 side facing football and 1 side facing baseball.

The current system is 3x SLX mics(2 handheld, 1 beltpack).

• The beltpack is meant to be used primarily for football referee calls, however it only works when in the bleachers...
• The handhelds work fine throughout the entire playing area of the football side and infield side of baseball.
• The 2 handhelds have a UA221 splitter between them and 1/2 wave antennas
• The 1 beltpack is direct to 1/2 wave antennas

To make the Beltpack work as they need I am looking into the following solutions/upgrades:

1. Add a UA844 Active Antenna Splitter
2. Move the Antennas so they are next to a window facing either playing field.
3. Swap to Active Antennas (directional or omni?)
   1. I'm worried/concerned that if I went as far as direction antennas(UA874US or UA864US?) I may not get enough coverage for both the baseball and football fields?
4. Replace the beltpack system with a QLXD system (Keeping the 2 handheld SLX systems)
   1. I like this option as the QLXD beltpack has a "Hi" output power feature

Is this a good process to go down?
Budget for only this is about $2000. (this is a part of a larger project that includes the stadium and 2 indoor gyms at the high school)


IMAGES below assuming they can help with recommendations/suggestions.

Here is a picture of the equipment rack: (The antennas are mounted to the top of the Equipment rack, see the 4 purple lines)

Here is a top view of the stadium: (The purple box in the middle is where in the press box the equipment rack is located)

Here is a section view of the football side: (Same as above about the purple box)

 

[FMEng]

The short range of the beltpack system suggests going over the basics first. Because there have been recent, major changes to the UHF TV spectrum, it could be as simple as a frequency conflict. Please tell us what the beltpack frequency is, and the frequencies for the two handhelds, along your city, state, and zip code.

 

[themuzicman]

This is a tricky setup! The first question I'd be asking myself is why exactly do the Shure SLX Handhelds work where the bodypack fails - you're halving the receive power of the handhelds using a passive splitter AND you have halfwaves on them AND they still work so clearly there are issues afoot! The Shure SLX1 bodypack is a fixed 30mW Tx power which should give you a little more range than just the bleachers. The first place I'd be looking at is 1. Frequency coordination and 2. The awful SLX Antenna.

On the coordination - run a quick frequency report in Wireless Workbench and just make sure things are happy in your neighborhood. After that, and full caveat - I haven't touched an SLX Receiver in years so bear with me if this isn't a feature in them, turn your squelch down and disengage any pilot tone that may be on, and see if you have some errant noise-floor breaking thru the receiver. Knowing it's SLX you probably don't have pilot tone, but it's still a troubleshooting step for other analog systems.

On the antenna - they are really delicate antennas. I'd be seeing if internally it was actually connected. This is honestly where my money is on as far as troubleshooting this issue.

-------
As far as dumping money into a problem:
My first thought upon seeing this was, "Oh, this telex antenna finally has a purpose" - I've seen it for years but never understood its use case!

So in a world free of budgets I'd be steering you into looking at a product like the PWS Alpha Series and a set of directional cardioid antennas, cross-firing like a stereo mic pair, one pair off the front of your booth and one pair off the back of your booth.

I understand you like the QLX-D's "Hi power" mode, but even at its highest it's still outputting a lower level than your SLX's (10mW vs 30mW) - the design philosophy with Shure is that they use low output transmitters into a powered antenna to boost the signal there, so counterintuitively just straight up swapping your SLX for QLX may actually bite you if you just stuck with half-waves on the QLX! There are other upsides and downsides to passive vs active antennas, but I figure it's just worth noting that

Anyhow, I'd start with a little more rigid troubleshooting of the SLX1 for the moment because back-end investment gets expensive quick, and the functioning handhelds is a clue that something is up.

 

[JJBerman]

The short range of the beltpack system suggests going over the basics first. Because there have been recent, major changes to the UHF TV spectrum, it could be as simple as a frequency conflict. Please tell us what the beltpack frequency is, and the frequencies for the two handhelds, along your city, state, and zip code.

City/State/Zip code = Middleton Wisconsin 53562
Here is a link to the coordinates in Google Maps: https://goo.gl/maps/9FkLh7RU7NqvgiJY8

Beltpack - H5 - Group 2 Channel 12 - 541.600MHz
Baseball Handheld - H5 - Group 2 Channel 10 - 536.425MHz
Football Handheld - G4 - Group 2 Channel 11 - 491.600MHz

I understand you like the QLX-D's "Hi power" mode, but even at its highest it's still outputting a lower level than your SLX's (10mW vs 30mW) - the design philosophy with Shure is that they use low output transmitters into a powered antenna to boost the signal there, so counterintuitively just straight up swapping your SLX for QLX may actually bite you if you just stuck with half-waves on the QLX! There are other upsides and downsides to passive vs active antennas, but I figure it's just worth noting that

Anyhow, I'd start with a little more rigid troubleshooting of the SLX1 for the moment because back-end investment gets expensive quick, and the functioning handhelds is a clue that something is up.

A separate reason I was going down the path of upgrading the back-end side is because everything in this equipment rack is around 20 years old.


When time allows, I have access to some UHF-R and ULX-D systems that I can bring out and test with. (This likely won't happen till next weekend at the earliest)
UHF-R is G1, ULX-D is G50 and H50(I think; new gear and I don't have it in my inventory yet)
That way I could get a real time spectrum scan in WWB and see if using a different beltpack system has different results.

 

[themuzicman]

So your coordination looks solid, I ran it thru IAS and tossed in the stuff you're going to test with in the future.

Anyhow, in the meantime I'd crack open the SLX1 and just make sure the antenna is still soldered in place. It's a very easy repair!

 

[FMEng]

You have WKOW transmitting on channel 26 (542-548 MHz), which is right above the beltpack frequency. It is 800,000 Watts, roughly 4 miles away. The mic receiver is trying to hear a pin drop next to a jet engine, causing receiver desensitization.

 

[JJBerman]

Sorry for not responding these last few days. Been super busy between 1st Job and 2nd Job...

I hope to have time this coming weekend to test out everyone's suggestions.
Thank you all very much for providing them!

I will respond with results once I have them. Have an awesome week!

 

[JJBerman]

So took me a lot longer to respond...

I was able to test everyone's suggestions and by changing the frequency to G2 C11 (538.500mhz) has so far worked without issue the past month and a half.

Thank you all for the suggestions!

 

[FMEng]

Thanks for letting us know. It's always nice to learn what the resolution turned out to be.