[RFI] Choir-type Mic More rone to RFI?

[Jim Brown]

On Wed, 17 Feb 2010 09:26:53 -0500, kd4e wrote:

>Would the little mics one sees hanging from
>the ceiling over church choirs be more prone
>to RFI in a Ham setup?

It depends on make and model. Products introduced more than about five 
years ago nearly all have serious pin 1 problems in the impedance 
converters that connect them to balanced audio cables, and the cables 
on either side of the impedance converter makes a great receiving 
antenna. The tiny mic capusules themselves are generally not 
susceptible. The same problems occur in the miniature "lavalier" mics 
connected to wireless systems, and to miniature mics that mount on 
podiums.

Shure and Audio Technica are two very good mfrs of mics like this 
whose older products were RFI dogs but whose newer products have fixed 
the problem. I've done consulting work for both companies on exactly 
this topic. :)  

What were you thinking of doing with a mic like this?  

73,

Jim Brown K9YC