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Interfacing Ke with MFJ929?

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DaveL G3TJP

Interfacing Ke with MFJ929?

I wonder if anyone has interfaced a K3 with an MFJ-929, used as a remote
tuner?

One of my antennas is a doublet fed with 450 ohm ladder line. The ideal
place for a tuner is at the base of the ladderline and I intend to
experiment with a variety of baluns to see which work best on which bands.
I have a suitable housing for the auto ATU and balun(s), which may end up
being switched remotely.

The auto tuner can be set to an automatic mode whereby feeding a few watts
of RF will generate a tune before adjusting power output of the K3 to the
required level, but I wonder if this can be done in a more automated manner?

Any help and guidance would be greatly appreciated.

73 Dave G3TJP

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Brian Hunt

Re: Interfacing Ke with MFJ929?

I have a MFJ-927 which is probably the same circuit board in a different, water resistant box. It's powered over the coax with a bias-T. It's set up to automatically tune when it sees RF. I give it about 5 watts of "TUN PWR" and it finds a match, usually pretty easily. Sometimes it's. Little flakey and seems to depend on where it's tuning from. You can watch it tune on the K3 display and see what it arrives at.

I use the 927 on 80-30m with a 92 ft doublet, 450 ohm window line and a 1:1 choke balun. SWR < 1.5:1 most of the time. Helps keep the losses in 130 ft of coax under control.

73,
Brian, K0DTJ
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Kidder, George

Re: Interfacing Ke with MFJ929?

In reply to this post by DaveL G3TJP

In CONFIG menu, TUN PWR defaults to NOR, where tuning power follows the
power knob. But TUN PWR can be pre-set to any other value, which it
will produce whenever the "xmit" button is held. (I have mine set for 50
W since my SWR indicators are manual). You could use 5W or anything
else. Is this "automated" enough?

George, W3HBM

On 11/6/2016 6:43 PM, Dave Lankshear wrote:

> I wonder if anyone has interfaced a K3 with an MFJ-929, used as a remote
> tuner?
>
>
>
> One of my antennas is a doublet fed with 450 ohm ladder line. The ideal
> place for a tuner is at the base of the ladderline and I intend to
> experiment with a variety of baluns to see which work best on which bands.
> I have a suitable housing for the auto ATU and balun(s), which may end up
> being switched remotely.
>
>
>
> The auto tuner can be set to an automatic mode whereby feeding a few watts
> of RF will generate a tune before adjusting power output of the K3 to the
> required level, but I wonder if this can be done in a more automated manner?
>
>
>
> Any help and guidance would be greatly appreciated.
>
>
>
> 73 Dave G3TJP
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

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Dave Fugleberg

Re: Interfacing Ke with MFJ929?

I use a SGC auto tuner in a similar configuration. Tuner at ground level,
40 feet of window line straight up to feed point of 130 foot doublet. TUN
PWR on the K3 is set to about 5 watts in the menu. Press and hold the XMIT
(Tune) button on the K3 and it tunes.
On Sun, Nov 6, 2016 at 7:05 PM George Kidder <[hidden email]> wrote:

> In CONFIG menu, TUN PWR defaults to NOR, where tuning power follows the
> power knob. But TUN PWR can be pre-set to any other value, which it
> will produce whenever the "xmit" button is held. (I have mine set for 50
> W since my SWR indicators are manual). You could use 5W or anything
> else. Is this "automated" enough?
>
> George, W3HBM
>
>
> On 11/6/2016 6:43 PM, Dave Lankshear wrote:
> > I wonder if anyone has interfaced a K3 with an MFJ-929, used as a remote
> > tuner?
> >
> >
> >
> > One of my antennas is a doublet fed with 450 ohm ladder line. The ideal
> > place for a tuner is at the base of the ladderline and I intend to
> > experiment with a variety of baluns to see which work best on which
> bands.
> > I have a suitable housing for the auto ATU and balun(s), which may end up
> > being switched remotely.
> >
> >
> >
> > The auto tuner can be set to an automatic mode whereby feeding a few
> watts
> > of RF will generate a tune before adjusting power output of the K3 to the
> > required level, but I wonder if this can be done in a more automated
> manner?
> >
> >
> >
> > Any help and guidance would be greatly appreciated.
> >
> >
> >
> > 73 Dave G3TJP
> >
> >
> >
> >
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>