Getting clear signals to 24 ULX Ps and Ss

Tapodhan

Member
Joined
Sep 13, 2012
Location
Wellesley MA
At our school in Wellesley MA we are running 12 ULX Ps and 12 ULX Ss. through 6 UA844s. The receivers are approx 75 feet from the stage. Due to the reduced number of groups and channels now available it is proving almost impossible to get even 10 uncompromised signals.
I have tried Shure's Wireless Frequency Finder that offers 11 channels in the J1 band and 8 channels in the G3 band - but, operated together I can still find only 8 or 9 channels free of interference. I have also used Wireless Work Bench - but it does not give me any better options.
Does anyone have experience of whether Registering with the FCC on a performance to performance basis actually improves the situation?
Is it time to persuade my school to invest in newer - digital - equipment?
Would digital body packs and receivers actually extend the number of available channels?
Small professional venues don't seem to suffer this problem - how do they handle it?
 

themuzicman

Well-Known Member
Joined
Apr 27, 2007
Location
On Tour
we are running 12 ULX Ps and 12 ULX Ss. through 6 UA844s. The receivers are approx 75 feet from the stage. Due to the reduced number of groups and channels now available it is proving almost impossible to get even 10 uncompromised signals.
What does your antenna distribution situation look like? The UA844's have no pass-through built in, are you running 6 full sets of remote antenna? Are you running stock whips into the UA844's? What do you mean the reduced number of channels and groups available? What we have available now is what we've had for at least the last 8 years, nothing has changed recently. You may have new DTV masts locally to you, but nationwide the same bandwidth is available for now.


Does anyone have experience of whether Registering with the FCC on a performance to performance basis actually improves the situation?
First, you need 50+ channels of RF to qualify for licensing with the FCC. Second, the license is non-exclusive. If you can't eek out your coordination now, FCC licensing won't help you at all, as I am willing to bet the majority of your issues are 1. DTV and 2. Yourself. The FCC licensing gives you the right to tell other folks to turn off if they interfere with you, provided that you can find them. The other big thing is that if they have a license too, you both have to work together to find a solution to your issues.

Is it time to persuade my school to invest in newer - digital - equipment?
Would digital body packs and receivers actually extend the number of available channels?
No, you don't need digital. Just get something that's freely tunable and not locked into frequency presets like you have now. Analog or digital, you just need something freely tunable, don't get hungup on digital as a buzzword.

Small professional venues don't seem to suffer this problem - how do they handle it?
Coordination, flexibility, and money. Having freely tunable wireless that splits multiple frequency bands (or has fairly large wide-band tuning). Coordination to make sure that you are fine within your own system, and then with the outside. Every now and again this requires scanning to make sure what the FCC says is there is actually all that is there. When you hit interference you attempt to find it, and not tune around it (especially if it is momentary interference, or new interference on a known-good coordination). Money to upgrade when you need to.
 

BobHealey

Active Member
Joined
Aug 6, 2011
Location
Troy, NY
At our school in Wellesley MA we are running 12 ULX Ps and 12 ULX Ss. through 6 UA844s. The receivers are approx 75 feet from the stage. Due to the reduced number of groups and channels now available it is proving almost impossible to get even 10 uncompromised signals.
I have tried Shure's Wireless Frequency Finder that offers 11 channels in the J1 band and 8 channels in the G3 band - but, operated together I can still find only 8 or 9 channels free of interference. I have also used Wireless Work Bench - but it does not give me any better options.
Does anyone have experience of whether Registering with the FCC on a performance to performance basis actually improves the situation?
Is it time to persuade my school to invest in newer - digital - equipment?
Would digital body packs and receivers actually extend the number of available channels?
Small professional venues don't seem to suffer this problem - how do they handle it?
I was curious, so I went into Wireless Workbench. You're dealing with 21 TV channel allocations around you. That's going to make packing in any density hard. Digital body packs per se won't help, but something that supports packing a lot more channels of wireless into a given spectrum might. Some of the newer, more expensive Shure product can go up to 17 channels of wireless in 1 TV channel. With the repacking going on, and the density of TV channels around you, I would make due or rent until the dust settles and its known where all those TV stations are going to land. You may also need to look outside the UHF band to either 900 MHz, or Shure supposedly is releasing their digital stuff in VHF real soon now.
 

Tapodhan

Member
Joined
Sep 13, 2012
Location
Wellesley MA
I was curious, so I went into Wireless Workbench. You're dealing with 21 TV channel allocations around you. That's going to make packing in any density hard. Digital body packs per se won't help, but something that supports packing a lot more channels of wireless into a given spectrum might. Some of the newer, more expensive Shure product can go up to 17 channels of wireless in 1 TV channel. With the repacking going on, and the density of TV channels around you, I would make due or rent until the dust settles and its known where all those TV stations are going to land. You may also need to look outside the UHF band to either 900 MHz, or Shure supposedly is releasing their digital stuff in VHF real soon now.
Thanks Bob, this is helpful.
 

themuzicman

Well-Known Member
Joined
Apr 27, 2007
Location
On Tour
Some of the UA844s have UA820D 554 - 590 antenna. Some have 470 - 542 depending on the channel range being received.
So just the stock whips...

At present you have a few things working against you in your system.

1. A congested DTV environment
2. Fixed Frequency wireless
3. Poor antenna distribution / Far from the stage

You can't fix #1, and #2 and #3 cost a bit of money to fix. If you're looking to throw money to fix the problem, I would attempt to fix antenna distribution to get your core system rock-solid and up to what the WWB report says you should be getting. I would look at getting 1 large antenna distribution hub, or multiple that allow Antenna A/B thru linking a set of remote antennas. I would look at getting a run of low-loss coax to run the 75' from your rack to deck, to position your antennas on deck. An antenna like the Sennheiser A2003-UHF is my first preference for things like this. Once you have a solid 10 channels, or whatever it may be, I would look at replacing some units with new units that have a large switching bandwidth that will be able to handle the upcoming FCC repackaging. Even something inexpensive like the Sennheiser ew100 G3 is better than what you have now, because it is frequency agile and not fixed.
 

Chris15

CBMod
CB Mods
Premium Member
Departed Member
Joined
Jul 15, 2005
Location
Sydney, Australia
It's been a few years since I've had hands on them, but the manual seems to support my memory that the ULX series along with the group and channel mode has the so called "master list mode" which renders it freely tunable within its available bandwidth.
That may improve things...
 

Tapodhan

Member
Joined
Sep 13, 2012
Location
Wellesley MA
So just the stock whips...

At present you have a few things working against you in your system.

1. A congested DTV environment
2. Fixed Frequency wireless
3. Poor antenna distribution / Far from the stage

You can't fix #1, and #2 and #3 cost a bit of money to fix. If you're looking to throw money to fix the problem, I would attempt to fix antenna distribution to get your core system rock-solid and up to what the WWB report says you should be getting. I would look at getting 1 large antenna distribution hub, or multiple that allow Antenna A/B thru linking a set of remote antennas. I would look at getting a run of low-loss coax to run the 75' from your rack to deck, to position your antennas on deck. An antenna like the Sennheiser A2003-UHF is my first preference for things like this. Once you have a solid 10 channels, or whatever it may be, I would look at replacing some units with new units that have a large switching bandwidth that will be able to handle the upcoming FCC repackaging. Even something inexpensive like the Sennheiser ew100 G3 is better than what you have now, because it is frequency agile and not fixed.
Thank you for this input. It is really helpful. I'm going to work on the antenna distribution issue right away and check for improvement. I'll also look into the purchasing some new units that can handle new FCC packaging.
 

Tapodhan

Member
Joined
Sep 13, 2012
Location
Wellesley MA
It's been a few years since I've had hands on them, but the manual seems to support my memory that the ULX series along with the group and channel mode has the so called "master list mode" which renders it freely tunable within its available bandwidth.
That may improve things...
Thanks, Chris. Yes it does, and I have tried using it with Wireless Workbench, but it seems that one of my major problems is a very crowded DTV environment.
 

BobHealey

Active Member
Joined
Aug 6, 2011
Location
Troy, NY
Thank you for this input. It is really helpful. I'm going to work on the antenna distribution issue right away and check for improvement. I'll also look into the purchasing some new units that can handle new FCC packaging.
Unfortunately, it is not yet known what that will be - they are still figuring it out. Take a look at the 600 MHz thread. It is quite possible you will end up with no usable UHF frequencies afterwards.