TimPitot Posted May 15, 2011 Report Share Posted May 15, 2011 Interesting. I will try to get my whole trx on my back and see if that helps. Thanks for your input, I like my SRa's too, don't really want to go back to Audio Ltd but if I can't improve this situation I may have to. Quote Link to comment Share on other sites More sharing options...
jason porter Posted May 15, 2011 Report Share Posted May 15, 2011 I have 2 UCR201's on BLK 26 as well as a Zaxcom Stereoline (old Tx, 90mw) with the filtered antenna (BLK 28) I get just a "tickle" of RF in my 201's, Zaxcom Tx is about 6" away from the nearest receiver. Quote Link to comment Share on other sites More sharing options...
rich Posted May 15, 2011 Report Share Posted May 15, 2011 With respect to the Zaxcom RF bleed issue, I'm using a setup right now with two SRa's in a bag and recently picked up a Zaxcom ZFR100 to use as a backup recorder (with the STA150). Even though the ZFR100 has no transmitter function at all, I'm STILL seeing plenty of RF bleed in my SRa's. Enough to cause them to display that "check freq" message. The only fix I've found so far is to get the ZFR100 far enough away by putting it up on the shoulder strap of the bag, but that is certainly an annoying way to operate. I don't understand why a flash-based recorder with no transmitter is leaking RF. Where is it coming from? Is there any fix, either on my end or Zaxcom's? I could try switching to 411a's but the whole point of this setup is to have the smallest, lightest rig possible, and for that I love the SRa. Rob where is the zaxcom sta150 power connector in relation to the sra receivers? its possible, though i would hope unlikely that the sta's regulated power supply could be emitting rf. does powering the zfr100 from its internal battery make any difference? Quote Link to comment Share on other sites More sharing options...
studiomprd Posted May 15, 2011 Report Share Posted May 15, 2011 " Open space in a casino 150 ft and it starts breaking up. " Casinos can be full of "RF spray's" and this applies: " why a flash-based recorder with no transmitter is leaking RF. " lots of digital devices spray RF, and the FCC requirements (notice that many consumer devices have FCC notices) are not all that stringent! Remember the issues with earlier SD 7xx recorders?? computers and other digital processors (including modern slot machines) are full of electronics operating at RF frequencies... Quote Link to comment Share on other sites More sharing options...
stephane Posted May 15, 2011 Report Share Posted May 15, 2011 where is the zaxcom sta150 power connector in relation to the sra receivers? its possible, though i would hope unlikely that the sta's regulated power supply could be emitting rf. does powering the zfr100 from its internal battery make any difference? I also have a ZFR100. Unfortunately, The STA stereo adapter only works with external power; The batteries only power the stand-alone ZFR100 as a mono recorder. However, my experience with the ZFR and two 411 in a bag hasn't been a problem. They're all fairly close together as well. Maybe I'm lucky. Stephane Quote Link to comment Share on other sites More sharing options...
JDirckze Posted May 15, 2011 Report Share Posted May 15, 2011 While I'm impressed that the 411's squashed the RF spray issue I should mention, switching over from the SRa to 411's didn't completely eliminate the RF spray from the Zaxcom. it just made the situation 'useable'. It's by no means a great situation, and I have to find frequencies at the lower end of the block, and keep my Zaxcom at the upper end of its block. I should also note that my block 27 411's also suffer from quite a bit of RF spray from my block 25 Zaxcom. So even having at least a block separation doesn't always help. What I did find was that the 411's managed to 'hold' on to a frequency better than the SRa. I'm taking a stab that this is what the front end tracking is all about. I've given up on having a light rig for now, it's much better to have a functioning rig than a light one... Quote Link to comment Share on other sites More sharing options...
studiomprd Posted May 15, 2011 Report Share Posted May 15, 2011 " I'm taking a stab that this is what the front end tracking is all about. " maybe... Quote Link to comment Share on other sites More sharing options...
TimPitot Posted May 15, 2011 Report Share Posted May 15, 2011 Just tried moving the trx900 away from my bag, no noticable difference, range is 30, maybe 40 feet before break up starts. Fail. Quote Link to comment Share on other sites More sharing options...
jason porter Posted May 15, 2011 Report Share Posted May 15, 2011 Tim, Something definitely isn't right... Are you positive it is the Zaxcom Tx causing the interference? With the Lectro Tx's OFF (Rx still on) and the Zax Tx ON, how much RF are you getting on the Lectro RF meter? Did you try it without the filtered antenna? (just curious if it made a difference) Do you have any fellow sound people in your area that you can swap gear with and see if they have the same problem? Just tried moving the trx900 away from my bag, no noticable difference, range is 30, maybe 40 feet before break up starts. Fail. Quote Link to comment Share on other sites More sharing options...
RadoStefanov Posted May 16, 2011 Report Share Posted May 16, 2011 the hop TX is on top my harness. far away from the bag... senator... I scanned when I got to the casino "Area at city center" I worked with g3 at exactly the same place and range was a lot better. I know you would say it depends... I switched off the talent smqvs and walked around for 5 minutes and got no RF on the sr. When I was closer everything was working fine. Running tx's and rx's in the same block in the same bag - I am amazed you get any reception on them at all! Quote Link to comment Share on other sites More sharing options...
pvanstry Posted May 16, 2011 Report Share Posted May 16, 2011 Here is my two cents on the SRa in bag. I have been using the SRa for a couple of months now, in bag. yes it is right that it is 90% of the time as good as a 411a. The 10% left is due to many reasons. Reason 1: Front end tracking. The way it works, as i understand, is that the receiver only open a 5mhz window centered on the selected frequency you dialed on it. A non-tracking unit, leaves it's entire 25mhz ( the block ) open. It means that the non-tracking unit is more suceptible to interaction in bethween trasmitter and also to the outside interference that add and produce intermod with the transmitters. Solution 1: Spread your SRa block. leave at least one empty block in bethween all of them ( ex: 20, 22, 24 ). This way, you will only have two transmiter in the same block. Thus giving you more flexibility when you need to move frequencies due to interference. Reason 2: Multiple Transmitters in the same room creates many intermod. Solution 2: When using multiple SRa, try switching the transmitters to 50mw. The creation of intermod will be lessen and you will actually gain range. I suspect that it is one of the reason for the SMv variable power. Reason 3: Camera Hop. Let's be clear, do not blame Lectrosonics for the RF spray that a Zaxcom transmitter creates. I have 3 SRa in bag and use anothe as a hop with LMa and i have NO SPRAY AT ALL from the LMa. I also have ( in my area ) as much range if not more then with a Zaxcom. Solution 3: DO NOT USE Zaxcom hop if you use SRa. ALso do not use 100mw transmitters in bag for hop send. LMa are perfect for this. ALso always have at least 2 empty block in bethween receivers and transmiters in bag ( ex: 21 for hop and 24 for bag ). I am not bashing Zaxcom but understand that if you need to get 411a to use a Zaxcom hop, when i use SRa all over, you are sacrificing your back and your money simply to use a product. I get at least 100' of range everywhere and have no issues so far. I have a bag that is as powerful in feature as a small cart ( 788/cl8, Sra etc... ) and weights less then a 552 with 4x 411a and hop. It's your health not mine. Reason 4: Knowledge. When using non-tracking units, you have to understand what is happening and be ready to react. You need to have spare frequencies ready and learn how to deal with RF issues. 411a are only filtering some of the issues but are still affected by the same issues. I found that they are actually more suceptible to the dreaded antenna switching clicking then the SRa. They seem to be switching more often, especially in reflective environment like the inside of a house. Solution 4: Learn about RF and prepare. I get upievery work day a little earlier and get to my location earlier to scan for possible rf issues. I note every problem i have and search for answer after. i spread my rf block more ( i have 21,22,24 and 470 ). I also try to use different block transmitter on peoples that will be interacting together closely. All of this you should also do when using any other wireless system. So is the SRa as good as 411a? In short, NO but when you accumulate all of the little things it brings to the table ( size, weight, power consumption etc... ) it is more versatile and makes a very strong and real argument in the long run. I now have one bag for all my shoots, no more rewiring late at night and countless hours spent on rebuilding kits, having multiples of the same things etc... I have ONE KIT. I am happy, producer are happy and totally impressed by the kit. Also, it happens only once i a while that i need to have anything over 50' of range. When it happens, i am usually outside so i turn my SMv to 250mw and get the range i need. Also since i am wireless to the camera, i simply get myself closer to the talent and add the range of my camera hop to my bag receivers that way. I also run 4 hours on a single NP1 for a 788/CL8, 3x SRa and 2x LMa. Again my two cents. Pascal Quote Link to comment Share on other sites More sharing options...
Rob Polhemus Posted May 16, 2011 Report Share Posted May 16, 2011 Thanks Pascal, I have been using wireless equipment for a long time and have a good knowlege of it but I can always learn more. Many of your points are good and valid. I do however have to say that Zaxcom and Lectro can live harmoniously if freq coordination is done and you aren't traveling outside the local area you coordinated for. Having said that I have been in situations where they (Zaxcom & Lectro) can and will fight one and other giving you less than desirable effects. I just wanted to say thanks for the learning opportunity. Each of us do things in our own way and it's good to see it from another perspective and maybe even learn a new way. Thanks for your two cents. Rob Quote Link to comment Share on other sites More sharing options...
chrisnewton Posted May 17, 2011 Report Share Posted May 17, 2011 Hi Pascal. How's block 470 working out for you in Montreal? Chris Newton, Ottawa. Quote Link to comment Share on other sites More sharing options...
pvanstry Posted May 17, 2011 Report Share Posted May 17, 2011 It's almost as clear as 24. Real good so far. BTW i have a pair of SMv block 470 for sale, they are new. Swapped to LMa for my camera hop. Pascal Quote Link to comment Share on other sites More sharing options...
JDirckze Posted May 17, 2011 Report Share Posted May 17, 2011 @Pascal - Seems like an awful lot of hoops to jump through for a useable rig. Each to his own I guess. For now I've given up the dream of using SRa's in the bag. Glad it's working out for you though! Quote Link to comment Share on other sites More sharing options...
Jack Norflus Posted May 17, 2011 Report Share Posted May 17, 2011 I am currently using Lectro 411a in spread in blocks 25 and 26, and Zaxcom QRX as a hop on 21 - I'm using the filtered antenna and all is good. Everyone plays nicely together. Quote Link to comment Share on other sites More sharing options...
Audio Daddyo Posted May 17, 2011 Report Share Posted May 17, 2011 I am currently using Lectro 411a in spread in blocks 25 and 26, and Zaxcom QRX as a hop on 21 - I'm using the filtered antenna and all is good. Everyone plays nicely together. Hey Jack have you tried the QRX without the filter antenna? Andy Quote Link to comment Share on other sites More sharing options...
PTA Posted May 17, 2011 Report Share Posted May 17, 2011 So I just did a little test because I have a Zax hop to play with and test at the moment. I have a couple 411's on block 21 and an SR on block 20. With the Zax turned on, it spreads a low levels RF across the board on my 411's, but on my SR it is noticeably lower across the board. I haven't done range or listening tests between the two in the field, but I was surprised my SR picked up a noticeably lower level of RF spill than my 411's. I am currently using Lectro 411a in spread in blocks 25 and 26, and Zaxcom QRX as a hop on 21 - I'm using the filtered antenna and all is good. Everyone plays nicely together. I'm definitely interested in possibly getting a QRX and an STA042 when it comes out, but I'm wondering how much of a difference the filter antenna makes as far as RF spill. Does it wipe out that low RF spill across the spectrum? Any noticeable difference in range/quality? Quote Link to comment Share on other sites More sharing options...
Jack Norflus Posted May 17, 2011 Report Share Posted May 17, 2011 Hey Jack have you tried the QRX without the filter antenna? Andy Yes I have - any everything seems to run fine without the filtered antenna. With the filtered antenna you loose a few dB of signal but I haven't noticed any if much loss. So my thought is it doesn't hurt to have it in-line. Plus I can mount my antenna high on my harness getting the RF further away from my bag. Quote Link to comment Share on other sites More sharing options...
Max Dumesnil Posted May 17, 2011 Report Share Posted May 17, 2011 Yes I have - any everything seems to run fine without the filtered antenna. With the filtered antenna you loose a few dB of signal but I haven't noticed any if much loss. So my thought is it doesn't hurt to have it in-line. Plus I can mount my antenna high on my harness getting the RF further away from my bag. Is the filtered antenna a Zaxcom product ? Do you have a link with more info or where to buy ? Thanks. Quote Link to comment Share on other sites More sharing options...
glenn Posted May 17, 2011 Report Share Posted May 17, 2011 Our filter antenna will eliminate any increase in the RF noise floor that might be picked up by a receiver in the sound bag by a receiver that is 2 blocks away from our transmitter. The filter has a passband loss of about 2 dB with about 40-50 dB of attenuation 2 blocks away from the transmitters block. The noise floor of our transmitter is about 90dB below our output level. This is normal for a transmitter of our type and within FCC and CE specifications. Combined with the filter antenna the noise output of our transmitter is better than -113dB. (+17dB-90dB-40dB) . If a receiver can be overloaded by our output under these conditions then it is a front end problem in the receiver. Any time transmitters are placed within inches of a receiver the results can be unpredictable. Our filter antenna and our micplexer take away that unpredictability when used with good quality receivers. Glenn Quote Link to comment Share on other sites More sharing options...
Audio Daddyo Posted May 17, 2011 Report Share Posted May 17, 2011 Yes I have - any everything seems to run fine without the filtered antenna. With the filtered antenna you loose a few dB of signal but I haven't noticed any if much loss. So my thought is it doesn't hurt to have it in-line. Plus I can mount my antenna high on my harness getting the RF further away from my bag. This has been discussed in other threads but I find when I use the filter antenna with my Zaxcom Goldline TX that I get significant loss in range and for that reason I don't use it. I have to change out my current block 29 Zaxcom Tx for a block 21 and will end up with the same 411 block and Zaxcom block configuration as you have and was just curious how much digial spray you have between your block 21 Zaxcom on your Block 25/26 411s. Andy Quote Link to comment Share on other sites More sharing options...
Jack Norflus Posted May 17, 2011 Report Share Posted May 17, 2011 just curious how much digial spray you have between your block 21 Zaxcom on your Block 25/26 411s. Andy A very small amount. After I do a scan on the 411's and I turn on my TRX900aa with STA100 I will get a bit of new RF on my 411's. But it is just a trace of RF, and with walk tests that I have done with both the Zaxcom on and off I am not getting an noticeable range reduction or hits on my Lectros. I think the scans that the 411's do are very sensitive. I found often a frequency with one or two "dots" on it will work fine. I've been in areas, without using my Zaxcom, after a scan every frequency showed at least two "dots" of RF. So I had no choice, and I had no RF or range issues at all. Quote Link to comment Share on other sites More sharing options...
PTA Posted May 17, 2011 Report Share Posted May 17, 2011 I was hoping some more people could chime in with their experience of Zaxcom's filter antenna. I did a search and got some info, but not a ton. I'm rally like the Zax system as a hop but I'm a bit turned off by the RF bleed into other blocks and I noticed I get bleed even with a Zax on block 25 and 411's on block 21 and SR on block 20. I know it's a manageable to work with but the whole idea of getting a new hop was to have a clean system. This is why the Lectro D4 was appealing, no pickup of RF bleed at all in my receivers even with the Tx right next to My RX's. Can anyone add some extra light to their thoughts on the filter antenna and bleed/range into their 411's or SR's? This has been discussed in other threads but I find when I use the filter antenna with my Zaxcom Goldline TX that I get significant loss in range and for that reason I don't use it. I have to change out my current block 29 Zaxcom Tx for a block 21 and will end up with the same 411 block and Zaxcom block configuration as you have and was just curious how much digial spray you have between your block 21 Zaxcom on your Block 25/26 411s. Andy Quote Link to comment Share on other sites More sharing options...
jason porter Posted May 17, 2011 Report Share Posted May 17, 2011 The antenna is a small box about the size of a Zippo lighter. It is basically a dipole antenna with a filter built in to limit the RF coming out of the Tx. I think it works very well, but it does cut down on the range a little bit. In my own unscientific test, I got about 10 feet less with the antenna than without. I think it is about $200. I can post a pic if you would like to see what it looks like. I was hoping some more people could chime in with their experience of Zaxcom's filter antenna. I did a search and got some info, but not a ton. I'm rally like the Zax system as a hop but I'm a bit turned off by the RF bleed into other blocks and I noticed I get bleed even with a Zax on block 2 5 and 411's on block 21 and SR on block 20. I know it's a manageable to work with but the whole idea of getting a new hop was to have a clean system. This is why the Lectro D4 was appealing, no pickup of RF bleed at all in my receivers even with the Tx right next to My RX's. Can anyone add some extra light to their thoughts on the filter antenna and bleed/range into their 411's or SR's? Quote Link to comment Share on other sites More sharing options...
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