the actual model is the MFJ-2501 antenna noise canceler. It is designed to take the input of 2 antennas (one being the main and the other for local noise pickup) and phase them in such a way as to remove the noise. I have one here and it works quite well. The only issue with these units is that they can only deal with one phased noise source at a time. These are the analog equivalent to DSP. THis unit has one little caveat: near the AM broadcast band, it can become overloaded and cease being functional (mostly by introducing more noise).

Hope this helps.

-eric

On Feb 1, 2014, at 9:39 PM, Howard Kaufman wrote:

> Eric, I wouldn't worry about the radio, but you might glow nicely when the 
> lights are off.
> 
> What is this MFJ 2500?  How does it work and how much is it?
> 
> 
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