Dave:
See my most recent post regarding how to switch the noise bridge in and out
of my antenna circuit, depending on whether I need to use my Ameritron
amplifier or not.
Perhaps I'm making this harder than it needs to be, but I would think the
noise bridge would have to be completely out of the antenna circuit if using
more than 600 watts, since I believe the maximum amount of power it can
handle is 300 watts.
Tom Behler: KB8TYJ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Dave Basden
Sent: Thursday, August 29, 2013 6:21 PM
To: [log in to unmask]
Subject: Re: MFJ Noise Bridge General Quiry
Hi Tom,
The noise bridge is a great way to initially adjust your external tuner.
Once the tuner is set for minimum noise, you can throw on your amp and fine
tune the SWR using the TW-1 if you like. That's what I have done here.
Again, it is important to turn down the RF gain and turn off the AGC.
Initially I thought it was a dud as I couldn't hear any noise reduction as I
adjusted the external tuner. Once I turned down the RF gain and turned off
the AGC, it was quite apparent where the noise lull was as I adjusted the
tuner.
73,
Dave, W7OQ
At 10:34 AM 8/29/2013, you wrote:
>Got it, Howard.
>
>These are good points to be noted for sure.
>
>I'll be interested in what others have to say, but I especially like
>the idea of not having to put a signal on the air.
>
>Does the noise bridge come with helpful instructions?? I ask this
>because in my experience with MFJ, their instruction manuals often
>leave a lot to be desired.
>
>Tom Behler: KB8TYJ
>
>
>-----Original Message-----
>From: For blind ham radio operators
>[mailto:[log in to unmask]]
>On Behalf Of Howard, W A 9 Y B W
>Sent: Thursday, August 29, 2013 1:26 PM
>To: [log in to unmask]
>Subject: Re: MFJ Noise Bridge General Quiry
>
>Tom,
>
>By using the SWR function on your TW1 in the tone mode, you can tune
>your tuner for the lowest pitch tone which will be of course the lowest
>SWR. In order to adjust your tuner, you will have to transmit a signal on
the air.
>
>With the MFJ or Vectronics tuner aid, you do not have to put a signal
>on the air.
>
>It must be noted that the tuner aid is rated at 300 watts or less. You
>would insert this right after your transceiver and adjust your tuner
>while bypassing your linear amp, if you have one.
>
>73
>
>Howard #3
>
>----- Original Message -----
>From: "Tom Behler" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Thursday, August 29, 2013 12:13 PM
>Subject: MFJ Noise Bridge General Quiry
>
>
> > Hi, all.
> >
> > Please forgive this quiry, since I'm certain that, for many on the
> > list, it is rather elementary.
> >
> > The recent discussion of the MFJ noise bridge, and its possible
> > discontinuation, is making me want to learn more about the product
> > and its potential usefulness for me.
> >
> > Right now, when I am working with antennas and my Tentech 238A
> > manual tuner, I use the LDG TW1 to measure SWR, and both forward and
> > reflected power.
> > Although I do find the TW1 to be less-than-totally accurate,
> > especially on the lower bands in comparison to the SWR/watt meter on
> > my TS590, it has been sufficient in meeting my needs at least for
> > the most part.
> >
> > Is there a compelling reason why I might want to consider purchasing
> > the MFJ noise bridge? In other words, what could it help me with
> > that the TW1 is unable to do?
> >
> > Of course, one could always make the argument that the MFJ noise
> > bridge could serve as a useful back-up, should my TW1 die, which may
> > be a good enough argument in and of itself.
> >
> > Just thinking out loud here, I guess.
> >
> > Tom Behler: KB8TYJ
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