sleah Posted March 17, 2014 Share Posted March 17, 2014 We are about to start performances of Alice in Wonderland.On Sunday we had our first tech run with 12ch of Line6 and all worked well. Today, we have just done a run but with an audience of Junior children. At least 3 of the mics just kept dropping out.Batteries were full, the other mics showed good rf signal strength. The one's playing up showed signal on the LCD that shows the individual antenna signals, but the main LED rf strength meter was either sitting down on one bar or jumping up and down like a VU meter!!With several mics on stage, it was the same one's playing up. Even when the actors stood fairly still. During the interval all the mics were left on a piano behind the set at the far end of the hall from the control (and receiver) position.Even with no-one in the room, the local computer wifi units powered off, the 3 units were still showing low rf. I tried retuning ch1 that was giving trouble. Putting it on ch13 and suddenly full power, which eliminates batteries, antenna issues and physical position issues. So my only last thought is interference. I though during act 1 that it could be kids phones, but as they all left the area during the interval and the problem persisted... and yes I did eliminate my own phone from the equation!!! Has anyone any ideas if this COULD be interference and what is likely to be causing it? For those who don't know, Line6 is digital 2.4GHz. I'm going to have to come back after hours to see if I can replicate the issue. Funny it was OK on Sunday :unsure: Stumped! :( Link to comment Share on other sites More sharing options...
smalljoshua Posted March 17, 2014 Share Posted March 17, 2014 Are these set to the WiFi friendly mode? I'm not completely familiar with the systems but know they have both a stomp on everything mode and a play nicely mode. Josh Link to comment Share on other sites More sharing options...
cedd Posted March 17, 2014 Share Posted March 17, 2014 Indeed, there are 2 modes of operation on the V75, and one mode of operation on the V70, so it depends a little which model they are. You want them in RF1 mode which uses the most robust frequency hopping scheme and has so far proven 100% reliable for me. RF2 mode is less robust but plays much nicer with wifi should you need to have it available at the same time. If you have a mixture of modes in use at the same time then all hell will break loose as they don't play well together. We had one transmitter that "slipped the net" when we switched them over and remained in RF2 mode. It didn't half cause trouble. Also check the manual when it comes to changing them over as I'm sure there's something funny like you've got to either hold a button or turn them off and back on again to store - I can't see a manual from here because of my silly work internet filter. V70's by default only have RF1 mode unless they've had their firmware flashed by a V75 unit. V75's have both available and I think by default come in RF2 mode, so need changing if you're running alongside V70's. Link to comment Share on other sites More sharing options...
Shez Posted March 17, 2014 Share Posted March 17, 2014 Batteries were full, the other mics showed good rf signal strength. The one's playing up showed signal on the LCD that shows the individual antenna signals, but the main LED rf strength meter was either sitting down on one bar or jumping up and down like a VU meter!!If memory serves, the RF signal meters on the LCD are signal strength meters but the LED ladder is a signal quality meter. If that's low, it suggests the data stream isn't making it through reliably, possibly due to interference. If you have a V75 receiver (or a V70 flashed with the newer firmware) have a look at its spectrum analyser - might show up some stray RF. There are some good free smartphone apps for spotting wifi networks too; I use oner called wifi analyser (Android). I'd certainly be checking the RF mode on every mic along with the transmit power setting. Your mention of ch.13 suggests you're in RF2 mode which is the "play nicely" mode although I think you can only use about six channels before you start stomping on wifi channels again. Getting them all on RF1 will likely solve this. Link to comment Share on other sites More sharing options...
Andrew C Posted March 17, 2014 Share Posted March 17, 2014 A more general speculate; difference between Sunday and Monday may be that every one is now back at work. Anything nasty locally? I know a local car park near here where Volvos would lock up. Line of site to Plod's radar workshop... Link to comment Share on other sites More sharing options...
sleah Posted March 17, 2014 Author Share Posted March 17, 2014 Update! I found one on RF1... So changed the lot to RF1 and it was as bad, if not worse. I then changed the lot to RF2 and it looks a LOT better! I had a play with the scan function with all tx's off. Quite interesting. Bearing in mind I have 12 units, all linked (rf wise) with one set of 360 paddles connected to rx 1 and daisy chained down to 12. The lower numbered channels showed little or no spurious rf, but the higher (11,12) showed lots spread over all 12 channels. Inserting the antenna in to receiver 7 and looping 12 back to 1, the spurios rf then became worse in the first 6 that the latter 6! All I can think is that the ones further down the daisy chain of receivers are getting a much amplified signal as it is passed from receiver to receiver.I have read that it's advisable to only run 6 receivers to a set of paddles, so longer term I shall invest in an extra set of paddles.Shame no one has them in stock for next day delivery, it looks like they have to be special order. How frustrating! We have another rehearsal tomorrow, so fingers crossed setting them to all rf2 has cracked it. Funny how using rf1 seemed to make it worse, that goes against everything people are saying here and on the Line 6 forum? :blink: Link to comment Share on other sites More sharing options...
MarkPAman Posted March 17, 2014 Share Posted March 17, 2014 Shame no one has them in stock for next day delivery, it looks like they have to be special order. How frustrating! Studiospares do or did when I posted this! Link to comment Share on other sites More sharing options...
Andrew Edwards Posted March 17, 2014 Share Posted March 17, 2014 You mention that one of them was on CH1, what were the other channels of the misbehaving mics? IIRC the channel numbers used by Line 6 are not quite the same as the channel numbers used for WiFi. WiFi channels 1 (2.412GHz), 6 (2.437GHz) and 11 (2.462Ghz) are the most common with 6 being the most common of all. You'll notice that channel 1 is .012 away from the start of the band which gives you some idea of the width of each channel. WiFi stops at channel 13 which is a little further away from 2.5Ghz than 1 is to 2.4GHz. I suspect that Line 6 push closer to 2.5 to get their 14 channels in. From conversations with someone that uses them, he avoids Line6 channels 6, 7 and 8 (if he can) as these are very close to WiFi channel 6. Having said this though, he has not had any problems with local WiFi. Indeed the last time he was in I was having an issue picking up my WiFi with my touch remote. Edit : reordered paragraphs for clarity Link to comment Share on other sites More sharing options...
cedd Posted March 17, 2014 Share Posted March 17, 2014 I suspect it may well be the fact you're running 12 in a chain that's causing you trouble. We tried it and had problems so reverted back to 2 chains of 6 (V70's, the V75's if memory serves me correct only allow chains of 4 - probably something to do with their self-termination rather than requiring the external terminator plugging in). Remember you don't HAVE to use the Line6 antennae. I use 2.4GHz flat plates bought online from a wifi shop and they work fine. They're also an awful lot cheaper! Link to comment Share on other sites More sharing options...
paulears Posted March 17, 2014 Share Posted March 17, 2014 My V70s all came with a terminator - and I put mine into racks of 4, which has worked really well with just the rubber ducks, not paddles. Link to comment Share on other sites More sharing options...
sleah Posted March 17, 2014 Author Share Posted March 17, 2014 Bit to chew on there, thanks folks. I did wonder about using alternative antenna. I could use a pair of the rubber ducks but would need to extend them outside of the rack. Hmmm. As Ynot would say B-) Link to comment Share on other sites More sharing options...
Shez Posted March 18, 2014 Share Posted March 18, 2014 IIRC the channel numbers used by Line 6 are not quite the same as the channel numbers used for WiFi.There's little correlation, mainly because each L6 channel uses more than one carrier - there's a list of frequencies here. There are details elsewhere on that site of which L6 channels avoid which wifi channels. The chain of 12 receivers is almost certainly the root of your problems. Although it's not particularly cheap, I bought the antennae distro as that solves all of those problems and gives useful front and back mounted connections (it distributes to eight receivers and you can daisy chain four of them on to the remaining four). (I don't have 12 ways yet but I'm getting there.) I suspect your increased troubles in RF1 mode are a symptom of your antennae problem (twice as many carriers being transmitted so much more potential for interference in the "distribution" system) - once that's sorted I would expect to see a big improvement in both modes. Link to comment Share on other sites More sharing options...
sleah Posted March 18, 2014 Author Share Posted March 18, 2014 Yes it is looking like the daisy chain is an issue. Strange how it's only recently been an issue :blink: All part of the fun! :) As a test/temporary measure, I'm going to split the antenna distribution between the main paddles and the supplied rubber ducks by extending the rubber ducks and taping them to the paddle mic stands.We have another daytime rehearsal today so it will be a good like-for-like test. Link to comment Share on other sites More sharing options...
cedd Posted March 18, 2014 Share Posted March 18, 2014 Reversing the direction of one of the daisy chains may work for you. So wire the A side starting at receiver 1, and the B side at receiver 12. That way at least one of them is within 6 receivers of an aerial. Worth a shot as a quick fix. Link to comment Share on other sites More sharing options...
sleah Posted March 18, 2014 Author Share Posted March 18, 2014 Well, I dug out the spare rubber duckies from storage and some bnc extensions.I split it in to 3 lots of 4. The paddles on 1 set and rubber duckies on the other 2. That combined with making sure they are all on rf 2 and we had significantly better results at this afternoon's rehearsal.Only one bombed out entirely for a moment, but I suspect it may have been the battery cover coming loose for a moment, as it lost all communication then came straight back on and was perfect after that. Aside from the Line6 kit working well, someone reported to IT support that they were having problems with their laptop on the network. They were connecting wireless and to the wireless tx right in the hall were we were rehearsing...... I can now confirm that using 12 chanels of Line6 does indeed knock out local wifi! A CAT5 cable fixed the laptop while were were rehearsing. :D Thankfully my line manager (who happens to be head of IT support) was pretty chilled about it and even suggested shutting off the wifi if it would cause ME problems. Now THAT'S co-operation! :D Link to comment Share on other sites More sharing options...
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