Equipment picking up radio signals

bmete · Post by **bmete** » Sat Dec 01, 2007 4:03 pm

Hi,This is a first for me..., I was recording in my home studio, when suddenly, I am picking up a Spanish radio station- playing American country music. ( There are no drugs or alcohol involved)What is strange is that I live in the country, and we have no Spanish speaking stations or programming in the area. ( must be short wave ).Has this happened to anyone else/ How do I keep the radio signals from interfering with the recording?Help!Thanks! Bob

aubreyz · Post by **aubreyz** » Sat Dec 01, 2007 4:45 pm

It's most likely a grounding/shield issue. This link may seem like overkill, but in my early days as an engineer, these kind of Rane notes were like my bible If everything is wired/grounded/shielded like these examples, interference would be very unlikely. http://rane.com/note151.htmlAub

bmete · Post by **bmete** » Sat Dec 01, 2007 6:42 pm

Thanks Aub,Cool website... added it to my favorites for future reference.I changed out some cables and you were right it went away.Bob

hummingbird · Post by **hummingbird** » Sun Dec 02, 2007 6:36 am

Hmmm, I get this sometimes in my headphones when mixing, something that sounds like the local radio station.Sometimes I'll be teaching a student and my speakers will start spitting out this odd buzz... and then my student will say their cell phone is on vibrate.Odd.

bmete · Post by **bmete** » Mon Dec 03, 2007 5:02 pm

Hi Vikki,It is odd, especially when it happens for the first time. What was strange for me was, we watched the movie "A Beautiful Mind" the night before, so when I heard "voices", I made sure my wife could here them also.. Bob

aubreyz · Post by **aubreyz** » Mon Dec 03, 2007 5:11 pm

Quote:Hmmm, I get this sometimes in my headphones when mixing, something that sounds like the local radio station.Sometimes I'll be teaching a student and my speakers will start spitting out this odd buzz... and then my student will say their cell phone is on vibrate.Odd.As far as I know the cell phone things doesn't have anything to do with wiring or grounding. When the cell is finding a tower it sends out a pretty hefty pulse for such a small device. You'll get that sound near just about any amplification circuit. I've heard the same thing on live news programs before...Radio stations??... probably wiring. Could be a faulty piece of gear, but most times it's an unbalanced to a balanced connection not shielded correctly. If it's shielded wrong, then the cable just acts like one big antenna Aub

geo · Post by **geo** » Tue Dec 04, 2007 5:44 am

If I crank the gain to 10 on my vocal mic input I pick up radio stations (and red line my meters), I'll check sheilding as well, thanks guys... Geo

justinatrecording · Post by **justinatrecording** » Tue Dec 04, 2007 10:29 am

Hey Guys,Yup, proper grounding and sheilding should prevent this stuff most of the time. But you should also keep in mind unbalanced vs. balanced signals. Kind of a big topic here, but generally signals on XLR and 1/4" TRS (the connector with two black rings instead of one) are balanced. Balanced signals are really good at rejecting RF (radio frequency) noise that is leaking into your cables.Unbalanced signals, especially instruments level runs like a guitar, are much more prone to this. This is, in part, why you may have heard it best to keep your guitar cables as short as possible.Another interesting note about your Spanish radio station... If it's inconsistent in nature, it could be mother nature. Given the right atmospheric conditions (yeah, that's right--the weather), radio signals can travel incredible distances. It's a phenomenon known as tropospheric ducting. Because it's condition dependent, my guess is that you'll only hear the signal on occasion, if not quite rarely. But it could easily be from another state.http://en.wikipedia.org/wiki/E-skipWhat can you do about it? Was it bleeding into your recorded tracks? Or just hearing it in the headphones? Sometimes it's as simple as moving the microphone or guitar around until it goes away. Other times, you can try turning off various pieces of gear to see if one thing is causing the problem. Beyond that, dedicated power for audio gear (and no lights) is key, along with conditioned and possibly balanced power, a dedicated ground and proper wiring, etc.Cheers,Justin

justinatrecording · Post by **justinatrecording** » Tue Dec 04, 2007 10:43 am

Howdy again,Regarding the cell phone interference: That is quite common, especially if your phone is at the edge of service. The electromagnetic fields are stronger than you might think (nice that we all have them next to our brains so often!) and can easily leak into audio gear, especially microphones.If you really must have your phone handy, you could try this: http://www.crownaudio.com/kb/entry/163/ I've never done this, but it probably will help. Cheers,Justin

bmete · Post by **bmete** » Thu Dec 06, 2007 6:33 am

Hi Justin,You are right on target about the weather..We were under a wind advisory that night (30-40MPH).now it makes a lot more sense!Bob

Equipment picking up radio signals

Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

Re: Equipment picking up radio signals

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