View Full Version : frequency scanner or ditch G2s?


Josh Bass
January 31st, 2014, 07:43 PM
Hey guys. I believe this has been touched on in other threads but I really want to hit it hard this time.

So they last several times I have tried to use my G2s, I run into serious problems with (I believe) interference. Can't remember last time if it was static or just total dropouts, but today I was getting total dropouts, I could watch the receiver LED readout and see the mute come on and the RF light go out in time with the dropouts. When I had the receiver and trans right near each other (like a few feet away), it was fine. 10 feet away, dropout city.

Yes, I am aware of the scanning function, and I am aware also of the sennheiser freq chart that shows what's good in what cities. According to both of those, I should have been in the clear (full RF bars on Receiver or trans, whichever shows that meter, scanning returned 4 channels available in each bank I tried). Still, dropout city.

It seems like every time I use this thing, I would have to manually go through all 32 channels to see which (if any) were REALLY clear, since the system can't seem to accurately tell me.

So, question is, should I get one of the $129 frequency scanners and use THAT to find what's really available in my location, or ditch the system.

I've heard the G3s are better with interference, but on the other hand, used Lectros, some of them, can be found on ebay for around $1000 or less. That's only a few hundred dollars difference and likely a substantial quality upgrade.

I know everyone says learn to find good frequencies, etc., but I've used a client/colleagues lectros a lot and you know what? We never tweak the frequency pots, and those things work all the time every time everywhere with no issues. They just work.

So, wondering your thoughts. Thanks.

Tom Morrow
February 1st, 2014, 02:54 AM
Was doing work with one actor on g2 and the other on g3. No interference but the g2 has a lower range and a few more dropouts. That is my experience: g2 isn't as reliable as g3.

Josh Bass
February 1st, 2014, 06:44 PM
Right, but g3s new are only few hundred less than certain used lectros, and lectros are pretty much guaranteed to be better.

Rob Neidig
February 3rd, 2014, 10:38 AM
Josh,

As others have said, the G3 is probably more reliable than the G2s, but the G2s should not be that unreliable unless something else is wrong. Is the antenna on the belt pack transmitter all bent up or something? You didn't mention which frequency band your system is. Hopefully it's not the "C" band, in the 700MHz frequencies, which is now illegal in the US. That could also be the source of the problem.

All that said, though, I would never steer anyone away from moving up to Lectro. The Sennheisers are good, but the Lectrosonics are a big step up in sound quality and reliability.

Have fun!

Rob

Josh Bass
February 3rd, 2014, 12:09 PM
They are 500 mhz range---518-529 or so. Bought the system locally in 2004 and didnt know jack about freq blocks or legal ranges so just took what they gave me. I ASSUME if they were in houston selling to houstonians they would sell a good block.

The antennas are a little less than straight but not bent out of shape horribly. Its from the way theyve been stored. I guess that could be it? Could attach pic.

Rick Reineke
February 3rd, 2014, 12:38 PM
The G3 portable receiver has diversity antenna system which helps reduce 'multi-path' interference. It will not help for other types of RF issues though.
To G2/3 built-in scanner only detects significant RF and is not adequate for congested areas IMO.
Try using the on-line Sennheiser frequency finder ( Sennheiser/FCC USA frequency finder (http://en-us.sennheiser.com/service-support-frequency-finder) ) and choose a frequency(s) within a vacant TV channel. If there are no vacant channels, choose one with low RF energy, 'Prx factor' of -80dBm or less. (lower= -80dBm is good, -85dBm is better) This method of channel selection made a very significant difference in my experience. If you have the $ for a RF scanner that would be recommended. Multiple systems' frequencies must be compatible as well for optimum performance.
Proper set-up is another important factor that should not be overlooked: , antenna line of sight, orientation, not touching skin, gain staging, ect, ect. A $3k Lectro or Zaxcom are not 'turn-it-on-and-go' either and same due diligence must be exercised using any wireless system.
PS- A $20 cable will sound better and be more reliable.

Josh Bass
February 3rd, 2014, 06:32 PM
Using the sennheiser scanner tells me most of my G2's block is safe--yet I still get the results I get.

As for the RF scanner, asked a local sound guy about getting one. He thinks they're way too complex, and the built in scanner in, say the Lectro 211 system would do just as well.

Last two incidents I've had with my system, Recvr was line of sight with trans, in fact about 20 or 30 ft away max (this last incident, probably not even 10.

I know wired is always the preferred option, sometimes not possible/practical. However I plan to a hardwire setup/adapter whatever I do.

In both the instances where it failed me recently, I thankfully had lectros on hand and once they were in use, everything was fine. I know they're not "magic", but they sure seem to be a lot less prone to problems than my G2, with 0 tweaking. Except for the very very occasional hit ("zzzzzt!", not the dropouts I'm experiencing with the G2), they've worked perfectly in every environment I've used them in.

Rick Reineke
February 4th, 2014, 11:20 AM
The built in scan function is not a reliable frequency selection method in busy RF environments. Try the previously mentioned Sennheiser on-line frequency finder method. If that method does not work and every thing else is set-up properly, the unit may be faulty and should be sent to a Sennheiser repair facility for evaluation.
It's not easy, but can normally find usable frequencies on the street in midtown Manhattan.. aka, RF hell. Not as bullet-proof as my Lectro 211/411s, but usable.
PS, The 'New Endian' smart phone app. frequency finder app. may be of interest.
See this discussion over at the JW audio group.
FreqFinder v2.0 - Equipment - JWSOUNDGROUP (http://jwsoundgroup.net/index.php?/topic/13461-freqfinder-v20/)

What Sennheiser frequency block do you have? In Houston, Sennheiser frequency Block A (518-554 MHz) does not seem to have many usable frequencies available .. another frequency block (and system) may be the logical option.
And what Lectro block(s) are you using?

Josh Bass
February 4th, 2014, 06:30 PM
Thanks for the app link.

Yes, talked to Senn today and they think based on my description (same stuff I told you guys) it might have 'broke bad" (POP CULTURE REFERENCE!!!!!), so I guess next step is to get an RMA/send it in.

Yes, I have block A, although my Senn goes from 518-529 or so. That's what I was sold years ago, didn't know to investigate/ask for anything different, it was from a local vendor so assumed Houstonians selling to Houstonians would = legal range for HOUSTON.

Lectros? Don't know. Those are a client's and though I've rented them a number of times and used them on shoots with that client, we never mess with the freq tuning unless somebody messed up and mixed the trans from one set with the receiver from another and it has to be tweaked so they match. Again, it's one of those things that's just "always worked" so never messed with it.

Rick Reineke
February 4th, 2014, 11:44 PM
As you're well aware of, wireless mics in general are NOT trouble-free, no matter how much one pays, if a frequency block is not compatible for a given area... it ain't. Additionally, the Sennheiser A-block does not appear to be the optimum block for Houston.
In any case, I suggest talking to your (knowledgeable?) rental house and ask about the 'trouble free' wireless mic frequency blocks in the Houston area . Lectro blocks and Sennheiser blocks are different, so keep that in mind. If I have time in the next few days I could check the FCC site and recommend a frequency block.. but you could do that yo'self.

Josh Bass
February 5th, 2014, 02:21 AM
yes. i would probably ask a rep from lectro or senn. block a may not have been optimum, but it worked fine for years with few to no issues (remember i said bought in 2004). anyway, if that block has become even less feasible in the last few years or something, i would probably make the jump to lectro with an optimum block rather than getting another g2 or even a g3.

Tom Morrow
February 9th, 2014, 12:31 AM
A while back, a Senn rep gave me my best secret for wireless setup with my g3: Before turning on the transmitter, take a look at the RF signal meter on the receiver. If you see a signal then you have interference, so find a new channel.

I don't really see how buying a scanner would give you a more accurate result than looking at the RF meter on the receiver, although I could see the scanner giving you a better idea of the overall situation. The g2 meter doesn't have as many segments as the g3 meter, so I'm not sure how well this works with g2.

Since I've been doing this, my issues with the g3 have been almost exclusively range issues; I get hits when the actors move but don't get hits when things are still.

Josh Bass
February 9th, 2014, 02:10 AM
According to everyone who's chimed in on threads like these (on this board and elsewhere), the G2's scanner (maybe G3's as well) are not responsive except to EXTREME interference, like dealbreaker interference. Lesser amounts that can still ruin your day without completely murdering the signal still get by, and it will tell that channel is "clear" or "open".

In that respect, a dedicated scanner would be able to do much more, walk around a room and see what in what freqs (if any) the RF spikes; tune around that if possible.

Anyway, I believe at this point there's something wrong with the unit. Of course when I test it at home, it works fine even at 100+ feet, and through walls (going strictly by the RF meter strength), but its hosed me on the last several locations I've been to (when telling me channels are open). I just can't believe it's coincidence, i.e. bad locations. I want to send it to Senn and have them take a look at both pieces, so working on getting that happening.

Paul R Johnson
February 9th, 2014, 05:04 AM
The rf section in a radio mic receiver is wide band, and interference from narrow band sources doesn't get displayed on the meter. A scanner can detect these narrow band spikes, very common with digital tv, and do it quickly. The scan function in the senheissers detects radio mic free channels, not always totally empty channels. An analyser lets you see visually the spectrum either side of your selected channel.

If you now get dropouts, that's a different thing altogether. In most cases dropouts are simply a factor of distance, or multiparty reflections. You are very close for dropouts like this. If there is local interference from other radio systems, then instead of dropout you get weird audio as the other system attempts to replace your audio. What happens if you turn the squelch off? Does the audio in the dropout just get very hissy, or totally vanish? We' re really needing to do some tests in controlled circumstances to fault find this one. With non-diversity equipment dropouts have no safety net, but don't normally cause problems this bad with just a few feet of distance.

Rick Reineke
February 9th, 2014, 10:26 AM
A while back, a Senn rep gave me my best secret for wireless setup with my g3: Before turning on the transmitter, take a look at the RF signal meter on the receiver
Yes, and this has been 'my' SOP for years, after ID'ing 'occupied' frequencies with a scanner and/or the Sennheiser frequency finder. Same goes for the Lectros. Due Dilligence

Brian P. Reynolds
February 9th, 2014, 04:19 PM
The 'published' frequency lists most times are just a waste of time & effort, what you NEED to know is what is happening 'right now'............
A scanner is worth the money if you are going to use radio mics seriously..... It shows what is around and also the harmonics that are created by adding another TX frequency (yours)
Things like Taxi's,CB radio's, construction sites, 2 way radio systems & other radio mic users will be the main problem and none of those would be listed, they may not be in direct competition with your frequency but its the harmonics that are the problem.

Buy RF Explorer model WSUB1G [TES82252P] | Seeedstudio (http://www.seeedstudio.com/depot/rf-explorer-model-wsub1g-p-922.html)
Checking Frequency Compatibility (http://ff.audiotechnica.com/index2.html)

Josh Bass
February 9th, 2014, 10:19 PM
What tests would you recommend? I've gotten great reception when watching the RF meter/walking away from transmitter at HOME, through walls and 50-100 feet away (hard to measure), no dropouts. ON LOCATION, the last few times, horrible problems when the trans/receivr were only a few feet away. The obvious answer is "bad location", but I've had the unit for about 10 years and it's on recently that it's started doing that. The occasional "zzzzzt!" hit? Sure, dropout city? Recent phenomenon. Don't know what tests I could do that would help more than sending it in to Senn.

I guess the big thing I'm afraid of is that I buy the scanner, use it, it tells me a certain channel/frequency is open, I set the G2 there, and it still has problems. Then I'm out $129 for that scanner (unless they have a generous return policy).

Brian P. Reynolds
February 9th, 2014, 10:50 PM
Are you ever going to use a radio mics in the future? If you are then you will use the scanner again.
The RF spectrum is CONSTANTLY changing, it's not a fixed thing. Yes if you are a fixed location like a theatre or studio it may not change much but location shooting is a totally different thing.

Nicholas de Kock
February 10th, 2014, 12:34 PM
Josh out of interest which scanner are you looking at?

Paul R Johnson
February 10th, 2014, 05:28 PM
Let's say you are working at a location where you've had the problem. Clearly the cause is not a permanent thing - if it was, the scan function of the radios would probably have rejected it - so whatever is wiping you out, is not transmitting all the time, and don't forget that if the issue is de-sense, which makes the receiver appear to be deaf, then the scanner will not help very much, because it's not the channel you are using that you need to check, it's those very close. Hence why I'm suggesting a analyser and not a scanner.

I'm not sure how it is in the States, but many scanners do NOT have continuous coverage as your FCC has rules. I have receivers that cover our UK channels, but US frequency block A is missing from some of them.

Brian P. Reynolds
February 10th, 2014, 05:49 PM
Here are some screen shots of my RF Explorer.....
I would use it a couple of times a week for location shoots..
Simple, cheap and effective.

Buy RF Explorer model WSUB1G [TES82252P] | Seeedstudio (http://www.seeedstudio.com/depot/rf-explorer-model-wsub1g-p-922.html)

Josh Bass
February 10th, 2014, 06:17 PM
Im not sure i understand the last question addressed to me (which scanner are you looking at?)

Anyway, ive now gotten the opinion of two pro sound guys who say they trust their lectro scanners and therefore dont use a separate scanner. I dont know how it is with the 211, but the 411 displays the freq range as a bar graph the shows where the rf spikes are, giving you a way to find a sweet spot where little to nothing else is going on. That sounds identical to what the rf explorer does.

I work almost exclusively in houston and have only once in more than 10 years left texas for work.

Thinking a good plan might be a lectro 211 system, two ost lavs with hardwire adapters. Then i have not only a backup lav but the option to go wired when i can.

Brian P. Reynolds
February 10th, 2014, 06:32 PM
It comes down to $$$$$$ Yes some Lectro's have RF display features but they cost a LOT more than the Senni G2 /G3.
You can use a laptop with Senni software to get a GREAT real time display.
Yes you can use 'WinRadio' WiNRADiO Communications - The future of radio. (http://www.winradio.com.au/) as an analiser that uses hardware + software + Laptop PC.
I comes down to how much info do you want and how much do you want to spend?

Josh Bass
February 11th, 2014, 06:13 PM
Being that I'm pretty sure there's something wrong with the unit (even if there isn't--with its track record lately there's no way I can even remotely trust it now), maybe it's a "sign" that it's time to upgrade to a higher class of audio. I figure go Lectro rather than get another lower end Senn system (i.e. G3).

When you look at used prices on some Lectros, they are not horrendously more costly than a new G3, plus, you're getting what is objectively a better system.

Brian P. Reynolds
February 11th, 2014, 06:38 PM
If you are going to buy S/H be mindful of the frequency block changes that are happening world wide.... Don't buy a unit that will be in a banned block in your area..... It could be a costly mistake.

Rick Reineke
February 12th, 2014, 10:38 AM
The reports I've read from folks who attend the proposed FCC auction meetings agree the 600MHz block (TV channels 36-52) are likely the next to go. Not immediately.. but soon.
This just in: The auction previously slated for this year would be delayed until 2015.

Josh Bass
February 12th, 2014, 06:33 PM
Yes, thanks. I'm well aware of that issue. I believe it's block 26 in Lectro terms that's up for debate now. I have a few folks I trust to advise me on what's safe for the foreseeable future.

HOWEVER, with that said, people in town are still using stuff in the 700 band with no problems.

Anyway, if anyone's curious, Sennheiser will not simply examine my G2 without automatically fixing it, which means just to find out if there's anything wrong I would potentially pay basically what I paid for the unit to have it repaired, without wanting to. So I'm kind of stuck.