phenix Posted September 11, 2015 Report Share Posted September 11, 2015 WE HAVE AN UPCOMING LOCATION SHOOT IN WHICH TALENT WILL BE WEARING A FARRADY CAGE SUIT. TESLA COIL WILL GENERATE ARTIFICIal lightning in the millions of volts whICh is to be deflected from talent by the suit. There will be experts on site.For your consideration:1) Will there be potential for damage to audio gear if talent is wearing a SMQV transmitter with Sanken COS-11 microphone while in the Farraday cage and while lightning is flowing around the cage? Could, possibly, components within the wireless or the microphone experience damaging inducted current or high voltage static charge -- even though the lightning would not be flowing through the talent's space within the cage?2) If the answer to 1) is "no" and wireless may function as normal and transmit under lightning conditions, will a lightning-effective Farraday Cage prevent 100-watt 600 mhz FM broadcast signal from reaching a receiver outside the Farraday Cage within 75 feet of the transmitter? 3) If answer to (2 is that signal will be received through the Farraday Cage, will the FM broadcast signal itself be effected significantly by the lightning bolts in the room? The wireless receiver may be in the same room as the lightning as it passes through the air from the tesla coil to its target in the room.4) Are there any safety issues that need attention regarding the talent wearing a metal piece of audio equipment while in a Farraday Cage? 5) Does anyone here have any suggestions for additional issues I should resolve prior to the lightning strike?There is a scout prior to shooting, so the answers to these questions can be determined empirically in advance of the shoot -- would anyone like to volunteer a wireless for the experiment?rphenix Quote Link to comment Share on other sites More sharing options...
atheisticmystic Posted September 11, 2015 Report Share Posted September 11, 2015 Fucking hilarious ! Donate a wireless kit ? Fuck, I'll donate a human volunteer !!! Prepare for the lightning strike ! Brilliant Quote Link to comment Share on other sites More sharing options...
Jack Norflus Posted September 11, 2015 Report Share Posted September 11, 2015 While I have no actual experience with this I would guess that no rf would penatrate the farraday cage. So unless the antenna is outside of the cage you are SOL. Quote Link to comment Share on other sites More sharing options...
Rachel Cameron Posted September 11, 2015 Report Share Posted September 11, 2015 (edited) Any audio collected would only be like... "GAHHHHHOOOOOWEEEEEEAAAAArrrrgaaaahhhhhhlordyTHAAAAATHURRRRRRRRTS", anyway. Set the limiters and stand back. (Sorry, I just couldn't refrain). Where are all the seriously knowledgable electronics brains here? Edit: Aside from Jack, I mean. Edited September 11, 2015 by Rachel Cameron Quote Link to comment Share on other sites More sharing options...
Freeheel Posted September 11, 2015 Report Share Posted September 11, 2015 i want to know where you got a 100 watt SMQV. Forget about the tesla coil, your wireless will burn the talent by itself... As for the other questions, I don't think your wireless transmission is going to like either the cage or the lightning, and the two in combination are like the ultimate worst case scenario. (I suppose they could be in a lead lined room as well- that might make it worse) Cheers, Brent Calkin Quote Link to comment Share on other sites More sharing options...
David Lezynski Posted September 12, 2015 Report Share Posted September 12, 2015 Had personal recording experience with "Omega Recoil" Tesla coil in Oakland a couple of years ago~~~ 8ft tall, Toroid about 6 ft diameter~~ million volts Transmitter out of the suit/cage at the time was 750Mhz lectro~~illegal but disposable~~~there's something Illegal/Irrational about a million volt anything IFB Lectro for talent was 670Mhz~~~ not disposable RF worked fine both directions with High Voltage operating However The Plasma arcing is really loud~~~~110 to 120db at 1ft ~~~the talent always wears hard muff hearing protection so IFB guzinta to talent is manageable, but the talent mic is a problem~~~Swiss Army Knife incision just below Adam's Apple was quickly ruled out. Really Old Sony ECM50 taped to the side of talent's mouth worked pretty OK ~~~~Strongly suggest wild VO. ~~~~~if you need realtime audio I'd rig up a David Clark Aviation Headset/Mic or sumptin like that. Quote Link to comment Share on other sites More sharing options...
Jay Rose Posted September 12, 2015 Report Share Posted September 12, 2015 I'd recommend a backup recorder wired to the mic, within the cage. And to be safe, a dynamic mic on one of its channels (better able to handle unexpected levels and RFI... though more sensitive to magnetic issues). Quote Link to comment Share on other sites More sharing options...
Mosdeaf Posted September 13, 2015 Report Share Posted September 13, 2015 Zaxcom wireless on your talent recording on micro SD card. I'm fairly certain someone on this site would be willing to volunteer a unit if you ask politely. Quote Link to comment Share on other sites More sharing options...
phenix Posted September 14, 2015 Author Report Share Posted September 14, 2015 All info very helpful. [Yes, SQMV would be 100mw not 100 watts!] This seems a good situation for use of recording device inside the suit. One mixer with Tesla coil experience cautioned that carbon fiber boompole in room with coil conducted stray current. He reported that Sound Devices 788 recorder case became "electrified" and that recorder froze, but recovered on reboot. Quote Link to comment Share on other sites More sharing options...
Rachel Cameron Posted September 14, 2015 Report Share Posted September 14, 2015 5) Does anyone here have any suggestions for additional issues I should resolve prior to the lightning strike?rphenix hmmm...asking if the production has insurance coverage for gear damage? Quote Link to comment Share on other sites More sharing options...
Earmuffs Posted September 15, 2015 Report Share Posted September 15, 2015 Is there a protective shield you could wrap the transmitter in a leave the antenna out? Sent from my SM-G920V using Tapatalk Quote Link to comment Share on other sites More sharing options...
phenix Posted September 16, 2015 Author Report Share Posted September 16, 2015 Yes, the first discussion on this was requirement that a Loss Payee Certificate be issued to the owner of any and all equipment delivered to the location for use in the shoot. Also, requirement that production insurance is in place for personal injury. Quote Link to comment Share on other sites More sharing options...
Bill Ruck Posted September 30, 2015 Report Share Posted September 30, 2015 That sounds like Lightning On Demand's Tesla coil. Worked with them at a couple of Survival Research Labs events. If the personal shield is tightly woven no UHF RF will get in or out. But the suit LOD used was very coarse and probably wouldn't stop UHF. Tesla coils run in the 10-20 kHz range. That's a very low frequency. It's difficult for a small UHF antenna to absorb much energy from that very low frequency. I did not try mic'ing the guy but probably your equipment will survive. And the comment about LOUD is true. I did record the SRK event but used 421's with a pad into the LINE input of a D7 DAT. Calculated 0 dBFS was 140 dBSPL. That recording has launched (lunched?) woofers from the infrasonic from their equipment -- the V-1 engine and the sonic cannon. Bill Ruck San Francisco Quote Link to comment Share on other sites More sharing options...
Philip Perkins Posted September 30, 2015 Report Share Posted September 30, 2015 Hiya Bill! phil p Quote Link to comment Share on other sites More sharing options...
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