ProSoundWeb Community

Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: Blake Cerenzia on January 06, 2019, 02:20:01 am

Title: UHF mic popping...
Post by: Blake Cerenzia on January 06, 2019, 02:20:01 am
The elementary school where I volunteer has a (fairly new) Audio-Technica ATW-3141 in their "rehearsal" space.
Mic works fine when powered on, but when transmitter is powered off, a brief popping sound comes through the speakers...

Not sure if the problem resides in the transmitter or receiver...  ???

Any advice appreciated, Blake.
Title: Re: UHF mic popping...
Post by: Don Boomer on January 06, 2019, 12:12:40 pm
Check your squelch settings on the receiver.
Title: Re: UHF mic popping...
Post by: Keith Broughton on January 06, 2019, 12:19:05 pm
As Don suggested, increase the squelch setting until popping stops.
Also consider changing frequency.
Turn off the transmitter and watch the RF meter on the receiver and see if there is any activity.
If there is, tune to another frequency (or channel) until there is little or no activity.
Re-tune the transmitter to match the receiver and you are good to go.
Title: Re: UHF mic popping...
Post by: Ike Zimbel on January 06, 2019, 12:22:14 pm
Check your squelch settings on the receiver.
+1 Also, it looks like you have five of those systems in your rack. Do they all exhibit the same fault, or just one? If just one, where are the other transmitters when this is happening? This could be a frequency issue, wherein the frequency that channel is set to has a higher noise floor than the others...when the Tx is off, the noise is momentarily exceeding the squelch setting. If this happens when the other Tx's are turned on and piled up in one place, it could be a frequency coordination and/or equipment handling issue.
Title: Re: UHF mic popping...
Post by: Mike Caldwell on January 06, 2019, 04:28:22 pm
What frequency group are those is in?

As suggested see what the receiver's metering is doing when the transmitters are powered off and what happens metering wise when you hear the pop.

What does the "pop" sound like, is it like a crack snap sound or is it a quick burst of noise like static in between radio stations.

I notice you have three Williams Sound hearing assistance transmitters mounted on top of the wireless receivers, where are the antennas for the hearing assistance system in relation to the wireless mic receiver antennas.

Is there any antenna distro unit for the wireless mic receivers?

What version receivers are those, the later 3100b series will do frequency scanning by group.
Title: Re: UHF mic popping...
Post by: Blake Cerenzia on January 06, 2019, 05:53:20 pm
What frequency group are those is in?

As suggested see what the receiver's metering is doing when the transmitters are powered off and what happens metering wise when you hear the pop.

What does the "pop" sound like, is it like a crack snap sound or is it a quick burst of noise like static in between radio stations.

I notice you have three Williams Sound hearing assistance transmitters mounted on top of the wireless receivers, where are the antennas for the hearing assistance system in relation to the wireless mic receiver antennas.

Is there any antenna distro unit for the wireless mic receivers?

What version receivers are those, the later 3100b series will do frequency scanning by group.

They're in the 541-566 MHz band, the pop sounds like a qucik burst of static. I don't think there is wireless distro, rather remotely located antennas. (I don't see an antenna combiner)

These are some of the last 3000 Series units before they did the major redesign...

Were installed when the school was rebuilt in 2016 by the A/V contractor.
Title: Re: UHF mic popping...
Post by: Mike Caldwell on January 06, 2019, 06:15:10 pm
They're in the 541-566 MHz band, the pop sounds like a qucik burst of static. I don't think there is wireless distro, rather remotely located antennas. (I don't see an antenna combiner)

These are some of the last 3000 Series units before they did the major redesign...

Were installed when the school was rebuilt in 2016 by the A/V contractor.

That would be a lot of antennas to remotely locate, but I have seen school AV contractors do a lot really stupid things!!
Are they just directly on the back of the receivers?

How often does the noise happen, you my have to just sit and stare at the receivers for a while.
You could raise the squelch level on all of them and see if that takes of it.

Have you re-tuned any of the mics, for what it's worth they all should be operating in the same frequency group of channels.

What do your three Williams Sound units do, are they all feeding completely different zones on different channels?
I don't how many times I've seen multiple hearing assist systems feeding overlapping zones all set on the same operating frequency.

Title: Re: UHF mic popping...
Post by: Blake Cerenzia on January 06, 2019, 06:27:45 pm
That would be a lot of antennas to remotely locate, but I have seen school AV contractors do a lot really stupid things!!
Are they just directly on the back of the receivers?

How often does the noise happen, you my have to just sit and stare at the receivers for a while.
You could raise the squelch level on all of them and see if that takes of it.

Have you re-tuned any of the mics, for what it's worth they all should be operating in the same frequency group of channels.

What do your three Williams Sound units do, are they all feeding completely different zones on different channels?
I don't how many times I've seen multiple hearing assist systems feeding overlapping zones all set on the same operating frequency.

There are two antennas on the opposite wall which likely are for the stage (the rack has wireless, video, DSP, amps for the music room, cafeteria, and gym all in one place.) I've seen contractors do stupid things, but this particular contractor has also done a lot bigger projects (like CenturyLink Field), so I have some confidence in their design...

The mics are a pain to retune (no IR sync), so I haven't messed with that yet. I don't know whats up the hearing assist, but I could decrease the power level (or even try turning off the unit for the music room, likely never used).

Will get the key for this space and try out some of these great tips (frequency, squelch, etc)!
Title: Re: UHF mic popping...
Post by: Mike Caldwell on January 06, 2019, 07:29:47 pm

The mics are a pain to retune (no IR sync), so I haven't messed with that yet. I don't know whats up the hearing assist, but I could decrease the power level (or even try turning off the unit for the music room, likely never used).



Don't tell me about retuning them, I have 24 of them and of course half of them are 600mhz.

The new 3000 series are nice with some updated features short of the body pac connector that will not work with the tried and true HIROSE mic connectors unless you buy their adapter cable.

I feel they should have kept the same 3000 series form factor with just an additional frequency group offering (actually they used to have a 400mhz group and dropped it ) and introduced what is the new series and called it the 3500 series.
.....rant over.
Title: Re: UHF mic popping...
Post by: Blake Cerenzia on January 06, 2019, 09:19:55 pm
Don't tell me about retuning them, I have 24 of them and of course half of them are 600mhz.

The new 3000 series are nice with some updated features short of the body pac connector that will not work with the tried and true HIROSE mic connectors unless you buy their adapter cable.

I feel they should have kept the same 3000 series form factor with just an additional frequency group offering (actually they used to have a 400mhz group and dropped it ) and introduced what is the new series and called it the 3500 series.
.....rant over.


That's fair. Of course, they are still better than the Shure LX we were using at the nearby high school until very recently...
Title: Re: UHF mic popping...
Post by: scottstephens on January 07, 2019, 09:45:20 am
Guys,

Can I just say that: I HATE any wireless anything in a metal rack behind a concrete wall.

Rant over.

Scott
Title: Re: UHF mic popping...
Post by: Blake Cerenzia on January 08, 2019, 07:37:33 pm
I've gotten it so the "loud pop" is now a "soft blip" by maxing out the squelch. Seems to be working great!
Title: Re: UHF mic popping...
Post by: Mark Cadwallader on January 08, 2019, 09:17:59 pm
Don't tell me about retuning them, I have 24 of them and of course half of them are 600mhz.

The new 3000 series are nice with some updated features short of the body pac connector that will not work with the tried and true HIROSE mic connectors unless you buy their adapter cable.

I feel they should have kept the same 3000 series form factor with just an additional frequency group offering (actually they used to have a 400mhz group and dropped it ) and introduced what is the new series and called it the 3500 series.
.....rant over.

Yep. I've abandoned my AT 3000 gear and moved to QLX-D, since none of the lavs and earworn mics would work with new AT gear. 
Title: Re: UHF mic popping...
Post by: Mike Caldwell on January 08, 2019, 09:27:48 pm
I've gotten it so the "loud pop" is now a "soft blip" by maxing out the squelch. Seems to be working great!

Actually I would not call that working great until you get no blips or pops. I think there is still another underlying issue.

Also keep in mind by maxing out the squelch you decreased the mic operating range.
Title: Re: UHF mic popping...
Post by: Jordan Wolf on January 09, 2019, 08:55:36 am
Is there anything nearby with a motor? HVAC, cooler unit, anything that kind of “kicks on”?
Title: Re: UHF mic popping...
Post by: Mike Caldwell on January 09, 2019, 09:03:17 am
Yep. I've abandoned my AT 3000 gear and moved to QLX-D, since none of the lavs and earworn mics would work with new AT gear.

The AT cH to cW body pack mic adapter cable looks decently built and works........but was there really a need to change connectors in the first place?
Title: Re: UHF mic popping...
Post by: Blake Cerenzia on January 09, 2019, 02:23:48 pm
Actually I would not call that working great until you get no blips or pops. I think there is still another underlying issue.

Also keep in mind by maxing out the squelch you decreased the mic operating range.

I don't get much time to play with this stuff, and at least the speakers won't be damaged overtime. Also they do have antenna distro, and in this case, I think any detriment to range will be minimal...
Title: Re: UHF mic popping...
Post by: scottstephens on January 10, 2019, 10:05:34 am
The AT cH to cW body pack mic adapter cable looks decently built and works........but was there really a need to change connectors in the first place?


I have 3 of the adapters. They are built very well. Infact, if you  are using the body packs, they are almost too heavy. Again, why change what works? $$$$

Scott