ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: Antenna distribution  (Read 3317 times)

Timmy Liland

  • Newbie
  • *
  • Offline Offline
  • Posts: 33
Antenna distribution
« on: January 23, 2017, 04:58:25 am »

I am rebuilding my wireless racks.
Can I take RF signal from a splitters antenna A and B (not cascade) output to a new splitters antenna input?
Logged

Mac Kerr

  • Old enough to know better
  • Administrator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 6470
  • Audio Plumber
Re: Antenna distribution
« Reply #1 on: January 23, 2017, 08:07:39 am »

I am rebuilding my wireless racks.
Can I take RF signal from a splitters antenna A and B (not cascade) output to a new splitters antenna input?

Yes, but only go 1 additional layer, so 2 antennas feeding a maximum of 16 receivers.

Mac
Logged

Ike Zimbel

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 430
  • I'm not a newbie, I just play one on the internet!
    • Zimbel Audio Productions
Re: Antenna distribution
« Reply #2 on: January 23, 2017, 10:46:06 am »

I am rebuilding my wireless racks.
Can I take RF signal from a splitters antenna A and B (not cascade) output to a new splitters antenna input?
What Mac said...but, why not use the cascade outputs? Typically they have either unity, or less gain than the main outputs, so they would help keep your noise floor down.
iz
Logged
~Ike Zimbel~
Wireless frequency coordination specialist.
Manufacturer's Representative (Canada)
Alteros Inc
Radio Active Designs
~416-720-0887~
ca.linkedin.com/pub/ike-zimbel/48/aa1/266

Timmy Liland

  • Newbie
  • *
  • Offline Offline
  • Posts: 33
Re: Antenna distribution
« Reply #3 on: January 24, 2017, 05:11:37 pm »

What Mac said...but, why not use the cascade outputs? Typically they have either unity, or less gain than the main outputs, so they would help keep your noise floor down.
iz

My AKG wireless systems are as follows:

Two racks with one PS4000W splitter (old type) and two DMS700, one rack with PS4000W and two WMS470.

According to the DMS700 setup guide page 8
(http://cloud.akg.com/8313/1472046465439_23_6.pdf) three splitters can be cascaded.

On some of my future gigs I will have to use the venue´s 4 ch Shure QLX-D with Shure antenna splitter, the artist´s (local music school) 4 ch Sennheiser EW500 G3 with Sennheiser antenna splitter and my own 10 ch AKG DMS700/800 and 2-4 additional WMS470 channels.

I am trying to find the best way to connect all these wireless systems to one antenna system.
(RFVenue Diversity Fin)

The best solution might be some ZAPD-21 – Passive Combiners in front of all the splitters.

This is the reason for my original post, can a splitter receive another splitters antenna out signal?
Logged

Keith Broughton

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3091
  • Toronto
Re: Antenna distribution
« Reply #4 on: January 24, 2017, 06:47:19 pm »



This is the reason for my original post, can a splitter receive another splitters antenna out signal?
Yes it can but I would be careful about cascading.
John Sulek and I were trouble shooting a visiting band's RF system that seemed to be taking way too many hits.
Turned out the 4 distribution amps were cascaded and the last 4 receivers were pretty much useless(downtown Toronto).
Tech said he had no problems before but not so in this environment.
Might have been better to have the first distro feeding directly each of the other 3 rather than cascading.
Perhaps some other RF types here will have a POV.
Logged
I don't care enough to be apathetic

Ike Zimbel

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 430
  • I'm not a newbie, I just play one on the internet!
    • Zimbel Audio Productions
Re: Antenna distribution
« Reply #5 on: January 24, 2017, 10:10:48 pm »

My AKG wireless systems are as follows:

Two racks with one PS4000W splitter (old type) and two DMS700, one rack with PS4000W and two WMS470.

According to the DMS700 setup guide page 8
(http://cloud.akg.com/8313/1472046465439_23_6.pdf) three splitters can be cascaded.

On some of my future gigs I will have to use the venue´s 4 ch Shure QLX-D with Shure antenna splitter, the artist´s (local music school) 4 ch Sennheiser EW500 G3 with Sennheiser antenna splitter and my own 10 ch AKG DMS700/800 and 2-4 additional WMS470 channels.

I am trying to find the best way to connect all these wireless systems to one antenna system.
(RFVenue Diversity Fin)

The best solution might be some ZAPD-21 – Passive Combiners in front of all the splitters.

This is the reason for my original post, can a splitter receive another splitters antenna out signal?
Yes, but the trick is to have the least number of cascaded antenna distribution amps (which is what these all are) to avoid what Keith describes in his post. The preferred method is to have one unit be the master and distribute to all of the other systems, but to do that you need a dedicated unit. So, the passive splitters might not be a bad compromise. In that scenario, you would split the antenna signal two ways and feed, say, the Sennheiser and the Shure DA's, and then take the cascade out of the Shure to your akg's.
Logged
~Ike Zimbel~
Wireless frequency coordination specialist.
Manufacturer's Representative (Canada)
Alteros Inc
Radio Active Designs
~416-720-0887~
ca.linkedin.com/pub/ike-zimbel/48/aa1/266

Keith Broughton

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3091
  • Toronto
Re: Antenna distribution
« Reply #6 on: January 25, 2017, 07:24:18 am »

Yes, but the trick is to have the least number of cascaded antenna distribution amps (which is what these all are) to avoid what Keith describes in his post. The preferred method is to have one unit be the master and distribute to all of the other systems, but to do that you need a dedicated unit. So, the passive splitters might not be a bad compromise. In that scenario, you would split the antenna signal two ways and feed, say, the Sennheiser and the Shure DA's, and then take the cascade out of the Shure to your akg's.
Good solution Ike.
The small loss in the passive antenna split would be nothing compared to the problems I saw in the rig I described.
Logged
I don't care enough to be apathetic

Jens Palm Bacher

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 315
    • Lydfabrikken
Re: Antenna distribution
« Reply #7 on: January 25, 2017, 08:13:13 am »

beware that akg use 8V antenne bias power
Logged

Karl Winkler

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 548
    • http://www.lectrosonics.com
Re: Antenna distribution
« Reply #8 on: January 26, 2017, 11:26:01 am »

Yes, but the trick is to have the least number of cascaded antenna distribution amps (which is what these all are) to avoid what Keith describes in his post. The preferred method is to have one unit be the master and distribute to all of the other systems, but to do that you need a dedicated unit. So, the passive splitters might not be a bad compromise. In that scenario, you would split the antenna signal two ways and feed, say, the Sennheiser and the Shure DA's, and then take the cascade out of the Shure to your akg's.

This makes sense to me, too. Often, with larger systems, some combination of initial split or distro then cascading makes sense.

Two things to watch for with cascading: first, make sure that the units in a cascade all cover the same passband. I've seen this not be the case too many times to mention, because it is an easy mistake.

Second: the farther down the cascade chain you go, you want to be more and more towards the center of the passband for the frequencies in the lower units. This is because cascading compounds the "ringing" at the edges of the filter passbands.

I've seen systems with 6 layers of cascading working just fine, because the guys who set it up followed these rules. I don't recommend it, but again it can work if you do it carefully and the gear is high quality.
Logged
Karl Winkler

Lectrosonics, Inc.
Pages: [1]   Go Up
 


Page created in 0.037 seconds with 21 queries.