Issues with EW100 G2 wireless lavs

H

HST

Member
Hi, hoping someone can help lead me in the right direction to solve some technical issues I’ve been having.

First let me apologize for my lack of knowledge in the sound department, so some of the things I’m questioning might be no-brainers. Usually I’ve worked with a sound guy, and up to this point I’ve never had to troubleshoot my lavs to this extent.

We’ve been using G2 EW100 microphones for the past 5 years and we’ve had very little issues – and occasional pop, but nothing major. I’ve always been very happy with their performance as well as the sennheiser headphones that we use. Lately though, I am constantly getting loud static POPS! They happen quickly, frequently and out of nowhere. We film with HVX200’s, varying with using 1-2 wireless systems running directly into the camera – no mixer.

Now here’s what I’ve tried to correct the issue:
-Changing the frequency. I have used the scan function to scan the U Bank channels and find a different frequency. As well I’ve tried manual tuning the frequency (through the tune function), normally to something drastically different. I’m located in Vancouver BC, and I haven’t been able to find a listing of available frequency’s. Does one exist?
-I’ve twisted, turned, adjusted wires and checked connections
-I’ve tried rolling with Pilot tone “on” and “off”
-I’ve tried raising and lowering the squelch (with pilot tone on).. usually I’m set to LO
-I’ve tried raising and lowering the AF out… usually I roll at -12
-I’ve tried raising and lowering the sensitivity (I usually shoot at -20)
-If we are on a tight shot I’ve tried unhooking the mic from the talents back and putting it in front to give a clearer path.
-I’ve switched microphones
-I’ve switched transmitters and receivers
-I tried a BRAND NEW out of the package microphone
-I borrowed a friends set of transmitter, receivers and microphone (hardly used) and still had the same issues.

I’m at a loss… like I said we’ve never really had problems and now it’s a daily thing, and nothing I do seems to solve it. This is not just in our studio but on location as well, numbers of different locations – so I don’t feel that location is the cause either.

Is there something I could possibly be doing wrong? Is there a proper way to find clean frequencies? Is there a way to tell if I don’t have solid connections (ie the mic is plugged in, the locking ring is screwed all the way tight – but could I be missing something?)
When searching for a clear channel, I set the channel on the receiver first. If there is any action on the RF channel this is an immediate sign that the channel is not clear, ya?
Once I’ve scanned for clear channels and set them, I scroll through the channels… if the RF light goes to green (and my transmitter is still turned off), this means there is already a signal hitting the channel so don’t pick that one, ya?

Let me know any thoughts you have, I feel like I've tried all the obvious - but maybe there is something I'm just not thinking about or that I don't even know!

Thanks in advance!
 
Last edited:
A few things that might help us help you:

1) What frequency block does your G2 system use?
2) Where are you located? (This can be very important, especially in relation to #1 above.)
3) Can you post a recorded sample (or two) of the offending interference?
 
It sounds like external interference.

Does it always happen at the same location? Or does it do it everywhere?

Personally I would talk to Sennheiser Canada.


PS - black text on a black background makes your original post virtually unreadable.
 
It has been happening everywhere.

Two of my packages are set to between 740.000-776.000 and the other package is set to 518.000-554.000

I live in Vancouver, BC, Canada.

Like I said, this is a new occurance - I've never had this issue before. After trying multiple frequencies, swapping mics etc I was certain that I was looking at there being some kind of technical issue in my transmitter-receivers. That is until I tried a brand new package on loan from a friend and had the same problem. I'm now completely baffled.

I guess all I can think of is that I'm not getting the clearest possible frequencies. What's the best meathod with the EW100 to find the cleanest signal?
 
Is there any other wireless running on set? IFB? Wireless video? Two-Way Radio? Are there smart phones on set? Wireless headphones (non bluetooth)? Laptops plugged into power supplies? (this one got me, and as soon as we unplugged the power supply to the laptop and ran it off batteries, the interference went away).

Halogen or flourecent lighting?

If this problem is happening with both your 500mhz and 700mhz systems then my guess is some electrical or electronic device in the near vacinity of the set is emitting a burst. This burst could be coming from a transmission or simply a data polling, light switches (and switching power supplies) or dimmers.
 
I know they're not in the same frequency but I was getting a lot of clicks during a conference shoot. I switched my cell phone off and the clicks went away. Same gear, Sennheiser G2 system.
 
I had a similar problem and found it related to my Cineroid Metal EVF. Mostly it was the power cable to D-tap that when replaced helped. The remainder was finding a different frequency. Occassionally I still get a pop.
 
Would there be any possibility that the issues could be coming from improper settings on the transmitter/receivers?

Are the more prone to pops say if the AF output or sensitivity is set to low?

I only ask because these are the only things I may have changed in the last little while that would be different than before, and I never had problems up until now.

Are there also certain frequencies within the range you have that you *should* be using... or is any channel fair game so long as you don't have any other RF when switching on the receiver?

Any tips on finding the cleanest channel?
 
adamr316 said:
I know they're not in the same frequency but I was getting a lot of clicks during a conference shoot. I switched my cell phone off and the clicks went away. Same gear, Sennheiser G2 system.
Click to expand...

Cell phones do cause a lot of interference - even in silent mode - especially smart phones, Blackberrys in particular.

Cell phones should be switched OFF or in Aircraft Mode.
 
So I never really did find a solution to this... still getting random pops and hits on microphones and I'm just finding I need to switch channels way more often than I used to. Is anyone else using these microphones and finding they have the same issue?
 
It was never clear exactly WHERE you are using this equipment? Is it in a fixed location like a studio or some dedicated venue? Are you shooting on location all over town? The fact that it is happening on both the 500MHz and 700MHz bands is an indication that the interference is STRONG and BROADBAND. And the fact that it just recently started happening, and EVEN with new/different equipment makes me agree that it is environmental and not equipment failure.

My very first guess would be that somebody on the crew (or talent?) just got a new cell phone. On most (all?) high-budget sets cell phones and any other wireless gadgets are BANNED completely, or at least required to be set to "aircraft" mode where they won't transmit.

There is a story (true?/apocryphal?) that a famous director would confiscate any offending cell phone or other device and physically nail it to the nearest door frame or fence post as a punishment and example to others. With more and more devices transmitting at will (including e-readers, etc.) this is becoming an even larger problem.

Is 700MHz equipment still legal in Canada? They were illegal in the US from 12-June-2010 http://www.fcc.gov/encyclopedia/wireless-microphones The bandwidth has been auctioned off to new users of the spectrum and it seems quite likely that will be a significant source of interference.
 
Last edited:
These issues were persisting on all locations, I did have a faulty mic though, so I'm going to retest tomorrow with the 500 mhz frequency and see what I get - I have a feeling this is the source of the problem though!!! :)
 
Razz16mm said:
700 Mhz band is off limits now for all of North America I believe. Leased to public communications providers. This could be a major part of your problem. Does your 500 Mhz set have the same issues with finding clear channels?

http://www.hlspectrumreview.com/2011/11/articles/auctions/canadas-upcoming-700-mhz-auction/
Click to expand...

HST said:
These issues were persisting on all locations, I did have a faulty mic though, so I'm going to retest tomorrow with the 500 mhz frequency and see what I get - I have a feeling this is the source of the problem though!!! :)
Click to expand...


If it's only the 700MHz kit it sounds like the problem is due to the illegal kit.

See if Sennheiser Canada can change the frequency block (it means swapping out the RF boards in both transmitter and receiver) - Sennheiser UK could do this to a G2, so Sennheiser Canada should be able to do it as well - but it's not cheap. The cost of doing two systems is likely to be about the same as the retail price of one new system I think.
 
Hi. I had exactly the same issue you described, also with a G2 package, frequency 518-554 Mhz.
3 years working fine with very rare cases of interferences, and suddenly I started to get noise so bad that I just couldn't use them anymore. But totally random. I even sent them to Sennheiser representatives here in Costa Rica, and they couldn't find anything wrong with them.

My solution:
I bought another set but G3, range 516-558 Mhz, and all good now.
I even learned that my transmiter works fine with the G3, so it was probably my receiver the one with some problem.
Or.... (my other guess), maybe it was related to the cellphone frequencies that some companies started using, and somehow the G3 are better shielded agains't that, who knows
 
More and more cell phones and other wireless consumer devices around every day. The blackberries are the worst, which even affect wired connections in some instances.
Additionally, cameras and other equipment also can emit an 'RF spray', which can compromise reception and add other extraneous noise. Try moving the transmitters/receivers further away from other gear if possible.
 
Well I contacted Sennheiser and my local Sennheiser distributor and found out that yes, the 700mhz band is off limits and they now have a rebate program for old G2's operating within this spectrum. The rebate they offer is $80, which I guess is better than nothing, but is almost a joke considering a new G3 system is over $800 (Canadian).

Anyway, that coupled with the fact that these mics are getting pretty long in the tooth is what I believe has been causing me all these headaches.

One last thing, and keep in mind I'm not an audio guy so this may sound foolish...
I've been rolling with AF out at -12 and Sensitivy around -20. I know this may change from person to person and location to location, but are these settings too low and could this be causing some kind of issue? I'm using an HVX200
 
Last edited:
HST said:
I've been rolling with AF out at -12 and Sensitivity around -20. I know this may change from person to person and location to location, but are these settings too low and could this be causing some kind of issue?
Click to expand...
Those settings would not be the cause of RF interference or reception loss.
The sensitivity of around -20 should be OK.. depending on how loud or quiet the source is and the mic being used. In any case the transmitter's sensitivity should be set as high as possible without inducing distortion.
The AF out setting of -12 would be OK also for mic level inputs.
 
I use the same setup, two G2's feeding directly into an HVX-200A, and I've heard the pops you are referring to as well. We discovered that a nearby storm would make the popping happen quite a bit, to the point where we had to call off a shoot one evening because of bad weather outside. So...how's the weather up there?
 
HST said:
So I never really did find a solution to this... still getting random pops and hits on microphones and I'm just finding I need to switch channels way more often than I used to. Is anyone else using these microphones and finding they have the same issue?
Click to expand...
Have you made sure there are no cell phones, iPhones, etc, etc in the vicinity? A "bladda bap - bladda bap - bladda bap" sound every 30 seconds or so can be caused by a nearby phone checking in with the network. Makes sure ALL such devices within about 50 yards are completely powered down, not just set to silent.
 
You must log in or register to reply here.
Back
Top