Hi Tom,

I just use a 9 volt battery in the noise bridge as one battery lasts for 
about one year.  I was worried about rf getting in to my 13.8 supply system 
through the noise bridge, so I've stuck with just the 9 volt battery.
  The center pin is plus.
Bob, K8LR, [log in to unmask]

----- Original Message ----- 
From: "Tom Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, September 03, 2013 9:34 AM
Subject: MFJ Noise Bridge: Another Question


Hi, all.

I have another question about the MFJ Noise Bridge we have been discussing.

I checked the MFJ web site, and found the MFJ 212 listed at a cost of $99,
which is what I expected.

They indicate that the device can be run either via a direct DC connection,
or a wallwart power supply, which costs another $14.

Rather than spending the $14 on the extra wallwart, I'd rather run the unit
off my rig runner via an Anderson Power Pole connection.

However, I'm not sure how the plug for the DC connection should be wired.
For example, is the tip positive?

In general, I'd be interested in how others on the list who have the noise
bridge power the unit.

Tom Behler: KB8TYJ