Thanks for the additional description and explanation Butch.
Very informative!
Tom Behler: KB8TYJ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Butch Bussen
Sent: Wednesday, January 01, 2014 6:17 PM
To: [log in to unmask]
Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant Frequency
Well, not really good for that. It sort of works, but if the match isn't 50
ohms, you won't find it. For that you need one of the older palamars or
such that you can change the impedence on. What these things are is
actually a wheat stone bridge. If you picture a diamond made from 4
resisters. Feed left and right ends with power, noise or whatever. If the
bridge is matched, there is no curent flow between the top and bottom
connection. Hope that makes sense. The 212 is set at 50 ohms, other
bridges have a variable resister so you can tell actuel impedence. You can
not transmit through these. I have forgotten once in a while and left the
212 on, it has relay protection built in it.
The older bridges su ch as the palamar and omegas do not. I've fried a
couple of those.
73
Butch
WA0VJR
Node 3148
Wallace, ks.
On Wed, 1 Jan 2014, Tom Behler wrote:
> Hi, again, everyone.
>
>
>
> Sometime late last Summer, someone on the list suggested that an MFJ
> 212 Noise Bridge might be useful for determining the resonant
> frequency of an antenna, even one that might be resonant outside the ham
bands.
>
>
>
> Is this possible, and, if so, how exactly might that be done?
>
>
>
> Tom Behler: KB8TYJ
>
>
>
>
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