Topic: RF and the SD 7xx series

[boojum]

Just a heads-up here.  I have had two experiences in the same venue where my 722 acted weird and dropped phantom power to one channel, dropped the link between inputs and so on.  In short it dropped a lot of settings and I lost the session from that point onward.  The only difference between this and other venues was that a guitarist was using a wireless hookup to his amp in both cases.  I switched to some Dogstar quad cables and that was the end of the problem.  I checked the SD website and they talk about RF interference as a problem.  The guy with the wireless had to get about 6' from my mic cables for it to happen.  But who knows, it might happen also at a greater distance.

L8R


link: http://www.sounddevices.com/tech/7series-rf-emissions.htm

[ghellquist]

Just to be very clear - the RF issue with the 722 is with it disturbing other equipment. It happens to sound recordists having the 722 in the same bag as one or more receivers, where the receiver sometimes get disturbances from RF leaking out of the 722. There is no talk on the site about the 722 beeing disturbed by outside RF. Sound recordists quite often run a transmitter in the same bag, sending sound to the camera, so any general RF problems should have been reported.

My conclusion is that you have a different problem from the one described there. As changing cables solved the problem it suggests an obvious culprit, but there may be more hiding behind the scenes. Please do check in with the SD people.

Gunnar

[mmedley.]

Yeah, this does not sound like an RF problem at all. You have something else strange happening. ghellquist summed it up quite nicely.

[boojum]

Gunnar, et al, I checked with SD and they seem to think it is a lithium cell spiking.  Hmmm.   The cables could just be a red herring.  I promised to tape in the same venue using a SONY LiIon and see what is happening.  SD has more faith in SONY than in Impact.  YMMV

Thanks for the input.

Cheers