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Title: Very heavy wireless use example
Post by: Pete Erskine on June 04, 2014, 01:39:38 PM
This is the spectrum at the CMT 2014 awards.  We are at the point that almost no more frequencies can be added, even if we dont check intermod.  The coord is separated into 7 zones.  We have 26 BTR systems!  Show has 352 freqs with 156 just for Comms.   This covers the main show and 3 performance areas outside.  Jeff Briggette did the coordination and has the scars to prove it.  Good job.  I am on the outside stages.

Please RAD, hurry up with your  UV-1G!  (http://radioactiverf.com/products/products/uv-1g-wireless-intercom-system/)

Title: Re: Very heavy wireless use example
Post by: Neil White on June 04, 2014, 01:58:08 PM
Show has 352 freqs with 156 just for Comms.

That is some pretty intense spectrum usage.

How far out did coordination start? I would think it was important to make sure that equipment that arrived on site was in appropriate band splits. Are there multiple vendors involved in supplying the RF systems?

Neil
Title: Re: Very heavy wireless use example
Post by: Mac Kerr on June 04, 2014, 04:11:30 PM
This is the spectrum at the CMT 2014 awards.  We are at the point that almost no more frequencies can be added, even if we dont check intermod.  The coord is separated into 7 zones.  We have 26 BTR systems!  Show has 352 freqs with 156 just for Comms.   This covers the main show and 3 performance areas outside.  Jeff Briggette did the coordination and has the scars to prove it.  Good job.  I am on the outside stages.

Please RAD, hurry up with your  UV-1G!  (http://radioactiverf.com/products/products/uv-1g-wireless-intercom-system/)

Hurry up with that gear, I need it for my show! There is nothing in the shop here in Nashville.

Mac
Title: Re: Very heavy wireless use example
Post by: Pete Erskine on June 04, 2014, 04:14:21 PM
How far out did coordination start? I would think it was important to make sure that equipment that arrived on site was in appropriate band splits. Are there multiple vendors involved in supplying the RF systems?

A site scan helps to establish a band plan.  As far as coordination goes, it's never too soon.  As it was some users showed up on site uncoordinated and were done on the fly.  Most of the shop equipment is done in time to have it programmed in the shop.

Main performing bands for the most part send in their needs early but sometimes not without prodding.

The wide area of our sites allowed the Main inside stage to coordinate with the adjacent Plaza stage and Red Carpet. The Plaza Stage then also coordinates with the stage 300' down the street which is not coordinated with the inside show or the Red carpet on the far side of the arena.

BTR's are coordinated to work everywhere.  The Plaza Stage uses multiple RX/TX antennas to distribute coverage to the Far stage and the Main Inside BTR system also distributes antenna comms to cover Dressing and loading dock areas.

The Inside Performance ares has a 3 node Riedel (FOH, Back stage, main TV truck) and a 4th Node is located by me outside on the Plaza Stage.  This 4th Node also connects to the Outside TV production truck as well as C3 Beltpacks and the 5 BTR systems here.

The Riedel system is programmed by Michael Garth and I do a little local programming at the Plaza stage.

Extreme care must be taken when there are multiple Artist programmers.  We always get a fresh copy and then inform each other that the local copy should be refreshed.  Total over write function is turned off - only send changes enabled.
Title: Re: Very heavy wireless use example
Post by: Neil White on June 05, 2014, 02:16:07 AM
BTR's are coordinated to work everywhere.  The Plaza Stage uses multiple RX/TX antennas to distribute coverage to the Far stage and the Main Inside BTR system also distributes antenna comms to cover Dressing and loading dock areas.

Are you using RF over fiber for the remote antennas? I assume none of the 2.4ghz wireless comms systems were an option because of the quantity of belt packs and wide area coverage required?

Extreme care must be taken when there are multiple Artist programmers.  We always get a fresh copy and then inform each other that the local copy should be refreshed.  Total over write function is turned off - only send changes enabled.

Do you both have full access to all the nodes on the system? Is it easiest for one user to do the bulk of the initial system configuration such as adding ports and creating conferences? Are you using the latest version of Director? The snapshot feature to record key states and levels that they added in 6.7 looks useful.

Neil
Title: Re: Very heavy wireless use example
Post by: TonyWilliams on June 05, 2014, 03:03:16 AM

This is the spectrum at the CMT 2014 awards.  We are at the point that almost no more frequencies can be added, even if we dont check intermod.  The coord is separated into 7 zones.  We have 26 BTR systems!  Show has 352 freqs with 156 just for Comms.   This covers the main show and 3 performance areas outside.  Jeff Briggette did the coordination and has the scars to prove it.  Good job.  I am on the outside stages.

Please RAD, hurry up with your  UV-1G!  (http://radioactiverf.com/products/products/uv-1g-wireless-intercom-system/)

Pete, it was good to meet you, and glad you were on the outdoor stages to help us out.


- Tony Williams
Title: Re: Very heavy wireless use example
Post by: Don Boomer on June 05, 2014, 10:40:13 AM
Hey Pete

What's the bandwidth of your graph?
Title: Re: Very heavy wireless use example
Post by: Cameron Stuckey on June 05, 2014, 02:06:27 PM
Pete, why was (what I'm guessing is) channel 42 open, but not filled with freqs?
Title: Re: Very heavy wireless use example
Post by: Mac Kerr on June 05, 2014, 03:35:56 PM
Hey Pete

What's the bandwidth of your graph?

The pink band in the middle is ch37 which is 6MHz wide. It looks like probably ch14 - ch50, or about 450MHz - 700MHz.

Mac
Title: Re: Very heavy wireless use example
Post by: Pete Erskine on June 05, 2014, 04:39:36 PM
What's the bandwidth of your graph?

channel 14 to 51.
Title: Re: Very heavy wireless use example
Post by: Pete Erskine on June 05, 2014, 04:43:31 PM
Pete, why was (what I'm guessing is) channel 42 open, but not filled with freqs?

Initially it was listed as DTV which it is but as you can see it's weak.  After the initial coord by Jeff, I came to do the outside stages and pointed out that it probably is way too week to affect inside RF and we unlisted it as DTV.  In the end I even put a few mics there even though the dtv noise floor was about -70.  Not ideal but when the TX is less than 20 feet to the antenna OK.
Title: Very heavy wireless use example
Post by: Pete Erskine on June 05, 2014, 04:57:58 PM
Are you using RF over fiber for the remote antennas? I assume none of the 2.4ghz wireless comms systems were an option because of the quantity of belt packs and wide area coverage required?

no, the show has always been done with coax remote antennas, not excessively long runs.  No budget or necessity for RFoF.   The main stage had a Shure US874 RX and 1-Senn A1031 TX antennas on 25' cables located at FOH.  A 2nd RX was located 150' at DSR for RX to get a little better beltpack reliability.  The remote stage had Shure US874 and Senn A2003 TX.  The TX antennas were all at about 20'.  RX antennas about 9'.  The outdoor remote stages were 250' runs.

Quote
Do you both have full access to all the nodes on the system? Is it easiest for one user to do the bulk of the initial system configuration such as adding ports and creating conferences? Are you using the latest version of Director? The snapshot feature to record key states and levels that they added in 6.7 looks useful.

We didn't bother segregating the access permissions.  All the initial programming was done by Gaff.  I came to the show after the main stage was up and rehearsing and then we shared by letting each other know when we were editing and sending changes.

Dir 6.7 state recall is of questionable use.  Can't quite think of when I would need it.

Another feature which is more interesting is that you can select what happens when you wake up an 1100 OLED panel.  Previously the action was done as well as waking up the panel.  Now you can specify that the first action only wakes the panel up.
Title: Re: Very heavy wireless use example
Post by: Cameron Stuckey on June 05, 2014, 08:13:32 PM
In the end I even put a few mics there even though the dtv noise floor was about -70.  Not ideal but when the TX is less than 20 feet to the antenna OK.

What's your opinion on hiding frequencies in a low power DTV channel? Only when necessary, of course, but what is the threshold strength you don't like to cross?

I'm fond of sticking the last minute ENG crews on low level DTV stations.
Title: Re: Very heavy wireless use example
Post by: Ross Goldman (2) on June 05, 2014, 10:16:06 PM
Hi Pete,

Thank you for sharing. Do you know what spectrum analyzer was used to generate the CSV file graphed in your screenshot?

Thanks,
Ross
Title: Re: Very heavy wireless use example
Post by: Mac Kerr on June 05, 2014, 10:30:26 PM
Hi Pete,

Thank you for sharing. Do you know what spectrum analyzer was used to generate the CSV file graphed in your screenshot?

Thanks,
Ross

Pete has an R&S, but that looks like the output from a TTi. I know there was also a TTi onsite.

Hey Pete, the racks are already broken down and rebuilt into 2 sets of 8 BTRs for my show.

Mac
Title: Re: Very heavy wireless use example
Post by: Cameron Stuckey on June 06, 2014, 02:31:57 AM
Pete has an R&S, but that looks like the output from a TTi.
Mac

For those curious, any spectrum analyzer that can generate a CSV file can be imported to IAS and displayed on the IMD graph. Off the top of my head that includes the TTi, RF Explorer, and WWB scans.
Title: Re: Very heavy wireless use example
Post by: Ross Goldman (2) on June 06, 2014, 03:25:25 PM
For those curious, any spectrum analyzer that can generate a CSV file can be imported to IAS and displayed on the IMD graph. Off the top of my head that includes the TTi, RF Explorer, and WWB scans.

The scan looks like a much finer RBW than I'm used to seeing from a TTi PSA1301T. The highest resolution I can get out of the 1301 is 15 kHz, which when imported into IAS, kind of looks like an Etch-a-sketch compared to the original post. (See attachment.) That being said, if I zoom in on the TTi, I can see more resolution on the TTi screen than on the imported IAS curve.

Looks like the newer, high-end PSA series 5 supports up to 300Hz RBW, though I can't find any for sale in the US, only the series 2.

I've gotten a much finer RBW out of an RF Explorer CSV output, but I've had some reliability issues that make me hesitant to use it when I've got the TTi on hand.

(https://dl.dropboxusercontent.com/u/266601/TTi.png)
Title: Re: Very heavy wireless use example
Post by: Cameron Stuckey on June 06, 2014, 05:36:54 PM
Ross, I'm assuming that your Etch-a-sketch trace was taken as a single csv with a bandwidth of ~250MHz? What I, and I assume Jeff and Pete do is take multiple traces of a much smaller bandwidth throughout the spectrum. My personal preference is 12MHz at 15kHz RBW. This usually leaves me with 20 individual CSV files that IAS can essentially compile for you if you import them all at the same time. Fantastic resolution when zooming in to find specific freqs in a venue.
Title: Re: Very heavy wireless use example
Post by: David Sturzenbecher on June 06, 2014, 05:39:36 PM
Correct me if I am wrong but when exporting a trace from a TTi the resolution is dictated by what is currently shown on the screen.


Sent from my iPhone using Tapatalk
Title: Re: Very heavy wireless use example
Post by: Ross Goldman (2) on June 07, 2014, 02:25:26 AM
Cameron and David, thanks for the tip on multiple exports with smaller bandwidths. Will try that next time.
Title: Re: Very heavy wireless use example
Post by: Jesse Stern on September 16, 2016, 08:27:23 PM
I've noticed too that this will in fact increase the resolution of your .csv data.  What I don't understand is why the RBW can't be adjusted independently of the span size shown on the TTi.  Why can't I just do 1 full UHF scan with the RBW set to 15khz for the sake of the .CSV export?  Even if the data can't be shown high resolution on the TTi screen I would think that it should still be able to save the trace data at 15khz resolution.

Cameron and David, thanks for the tip on multiple exports with smaller bandwidths. Will try that next time.
Title: Re: Very heavy wireless use example
Post by: Henry Cohen on September 18, 2016, 12:43:25 PM
I've noticed too that this will in fact increase the resolution of your .csv data.  What I don't understand is why the RBW can't be adjusted independently of the span size shown on the TTi.  Why can't I just do 1 full UHF scan with the RBW set to 15khz for the sake of the .CSV export?  Even if the data can't be shown high resolution on the TTi screen I would think that it should still be able to save the trace data at 15khz resolution.

Not enough processing power and the RF stage likely has inadequate selectivity.
Title: Re: Very heavy wireless use example
Post by: Roland Clarke on September 18, 2016, 05:34:00 PM
This is the spectrum at the CMT 2014 awards.  We are at the point that almost no more frequencies can be added, even if we dont check intermod.  The coord is separated into 7 zones.  We have 26 BTR systems!  Show has 352 freqs with 156 just for Comms.   This covers the main show and 3 performance areas outside.  Jeff Briggette did the coordination and has the scars to prove it.  Good job.  I am on the outside stages.

Please RAD, hurry up with your  UV-1G!  (http://radioactiverf.com/products/products/uv-1g-wireless-intercom-system/)

It's an interesting project, what I do wonder about is that with 156 frequencies used for comms, why they didn't look for alternative solutions and simplify the whole thing?
Title: Re: Very heavy wireless use example
Post by: Diogo Nunes Pereira on September 18, 2016, 06:04:28 PM
What I don't understand is why the RBW can't be adjusted independently of the span size shown on the TTi.  Why can't I just do 1 full UHF scan with the RBW set to 15khz for the sake of the .CSV export?

Don't know about the PSA but I also wished that RBW could be adjusted in the RFExplorer independent of the span.

My usual settings for good resolution in WWB has me exporting 16 CSV files each with 28MHz span.

My tutorial on how do this can be found here:

http://shure-community.custhelp.com/posts/2dd89376b3

Gotta love when a nice topic from a couple of years ago suddenly resurfaces.

Sent from my Xylophone using Tapatalk...

Title: Re: Very heavy wireless use example
Post by: Jason Glass on September 18, 2016, 08:29:54 PM
Not enough processing power and the RF stage likely has inadequate selectivity.
All of the spectrum measurement challenges in this thread are why I love, love, LOVE my Signal Hound BB60C. It sweeps stupid fast, catches transients and FHSS signals, can do enormous spans with fine RBW's, has a super-linear front end with a quiet and gain-selectable preamp, internal selectable stepped value attenuator, and exports CSV files that require only minor tweaking to import into IAS and WWB6.

Sent from my mobile phone. Please excuse the inevitable spelling and grammatical errors.

Title: Re: Very heavy wireless use example
Post by: Mac Kerr on September 18, 2016, 08:51:34 PM
All of the spectrum measurement challenges in this thread are why I love, love, LOVE my Signal Hound BB60C. It sweeps stupid fast, catches transients and FHSS signals, can do enormous spans with fine RBW's, has a super-linear front end with a quiet and gain-selectable preamp, internal selectable stepped value attenuator, and exports CSV files that require only minor tweaking to import into IAS and WWB6.

Jason, how do you really feel?

See ya in DC in a couple of weeks.

Mac
Title: Re: Very heavy wireless use example
Post by: Jason Glass on September 18, 2016, 09:49:50 PM
Jason, how do you really feel?

See ya in DC in a couple of weeks.

Mac
Haha! I've owned or used the same RF instruments that most of the SR community has, and can't control my enthusiasm now that I've found the right tool for the job. ;-)

I'm also looking forward to our upcoming weeks in paradise. The gig may be in the center of a political cesspool, but I'm happy that the theater is well shielded (from RF- unfortunately not from politics) and that we'll be long gone by Nov. 8!

Sent from my mobile phone. Please excuse the inevitable spelling and grammatical errors.

Title: Re: Very heavy wireless use example
Post by: Jesse Stern on September 20, 2016, 05:15:31 PM
The Signal Hound looks cool but I would like to still have something that can operate as a standalone unit for capturing .CSV scans without needing to be hooked up to my laptop.  I'm currently using setup files I downloaded from Pete Erskine's site that scan the UHF spectrum I need to see in 3 separate scans:  470-542, 542-626, and 626-698.  It gets me useful scan data for IAS but still seems tedious that I have to do 3 scans just to get some decent resolution. 

Is there a way to set an "exclusion threshold" in IAS to disqualify potential frequencies based on the imported scan data?  I would like to set it to avoid anywhere that shows over -80db on the scan, similar to how WWB does.

All of the spectrum measurement challenges in this thread are why I love, love, LOVE my Signal Hound BB60C. It sweeps stupid fast, catches transients and FHSS signals, can do enormous spans with fine RBW's, has a super-linear front end with a quiet and gain-selectable preamp, internal selectable stepped value attenuator, and exports CSV files that require only minor tweaking to import into IAS and WWB6.

Sent from my mobile phone. Please excuse the inevitable spelling and grammatical errors.
Title: Re: Very heavy wireless use example
Post by: Jason Glass on September 20, 2016, 07:19:32 PM
The Signal Hound looks cool but I would like to still have something that can operate as a standalone unit for capturing .CSV scans without needing to be hooked up to my laptop.  I'm currently using setup files I downloaded from Pete Erskine's site that scan the UHF spectrum I need to see in 3 separate scans:  470-542, 542-626, and 626-698.  It gets me useful scan data for IAS but still seems tedious that I have to do 3 scans just to get some decent resolution. 

Is there a way to set an "exclusion threshold" in IAS to disqualify potential frequencies based on the imported scan data?  I would like to set it to avoid anywhere that shows over -80db on the scan, similar to how WWB does.
It won't let you set a threshold and do it automatically as WWB6 will, but you can right click on the graph and set exclusion ranges manually.

Sent from my mobile phone. Please excuse the inevitable spelling and grammatical errors.

Title: Re: Very heavy wireless use example
Post by: Jesse Stern on September 24, 2016, 01:12:51 PM
It won't let you set a threshold and do it automatically as WWB6 will, but you can right click on the graph and set exclusion ranges manually.

Sent from my mobile phone. Please excuse the inevitable spelling and grammatical errors.

I just heard from someone at Professional Wireless that scan-based exclusions is a feature they are planning to implement on the next version. 

I'm hoping they also add some functionality like multi-select, the ability to sort your frequency lists alphabetically, lock/unlock entire assignments, analyze a freq from your list without deleting and re-adding it, ect... and stop making it scroll back to the top of the list everytime I recalculate anything!