View Full Version : Radio interference


Jerry Jesion
March 26th, 2006, 02:38 PM
I am having some problems with radio interference when recording on my Korg D3200 mixer. I have good mics, new XLR cables and am plugging into grounded outlets. It is a local AM radio station that has the transmitter about 2 miles away. I have also had problems at another location much further away (probably another station). It seems to be related to the XLR cables. I plugged a Sony ECM 44b lav directly in to the mixer and did not have any radio pickup at all. I thought that XLR cables were shielded to prevent this problem. Is there anything that I can do about this? I cannot afford to have problems in the field.

Regards,
Jerry

Sam Gates
March 26th, 2006, 06:22 PM
Jerry,
Neutrik EMC Series connectors may help.

There are some good papers on RF problems and dealing with them on Jim Browns site. http://www.audiosystemsgroup.com/
Look at the papers on pin 1 problems and understanding RF interference.


Sam Gates

Seth Bloombaum
March 26th, 2006, 10:35 PM
So-called "quad" xlr cables may help. They resist RF somewhat better than a standard cable.

Most of the major manufacturers have them, they have 4 conductors (plus shield), in two twisted pairs that are then twisted around each other. Then each pair goes to a pin. This is a lousy explanation, you'd find more info at http://canare.com/files/Cat11_p35.pdf.

Douglas Spotted Eagle
March 27th, 2006, 12:23 AM
So-called "quad" xlr cables may help. They resist RF somewhat better than a standard cable.

Most of the major manufacturers have them, they have 4 conductors (plus shield), in two twisted pairs that are then twisted around each other. Then each pair goes to a pin. This is a lousy explanation, you'd find more info at http://canare.com/files/Cat11_p35.pdf.

If you go the Quad route, be aware that they wear out much faster than other cables, due to the fine/thin strands. I thought I was losing my mind a few years back when having problems with a couple cables. Fred Ginsberg took out a knife and showed me where the problem lay. Coiling/uncoiling the quads will cause early failure. But they are better in bad RF situations, supposedly.