Butch:


Well, I'm not expecting miracles from the unit--just trying to extend the
auto tuner's tuning range a bit on 80 meters.

There is a bypass position, where the unit  is out of the circuit, and where
the rig and auto-tuner behave as they normally would if the extender was not
used.

There also is the "off position", which I think is where the dummy load
connection becomes relevant.

I am hoping to give the extender  a test during this week-end's NAQP CW
contest.

I guess time will tell if it was worth the $79 or not.


Tom Behler: KB8TYJ

-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Butch Bussen
Sent: Tuesday, July 29, 2014 10:13 AM
To: [log in to unmask]
Subject: Re: Question On MFJ Auto-tuner extender

I used one and never did hook up a dummy load.  All it does as i recall is
add capacatance across the line.  I never had much luck with mine. 
It would let the rig tune, but no one could ever hear me.  If I remember,
there is a position where it is out of the circuit
73
Butch
WA0VJR
Node 3148
Wallace, ks.


On Mon, 28 Jul
2014, Tom Behler wrote:

> Hi again, everyone.
>
> In line with what I discussed on the list several weeks ago, I have 
> just purchased and received the MFJ 914 auto-tuner extender for my 
> TS480 HF set up out at the RV.
>
> I use an Alpha Delta DXCC HF antenna out there, and have had good luck 
> with it so far.  The rig's internal auto-tuner  tunes on all of 40, 
> 20, 15, and
> 10 meters.
>
> My rationale for the purchase centered around the idea that I might be 
> able to extend the TS480's auto-tuner range on 80 meters.  The DXCC 
> tunes well in the middle 150 KHZ of the band, so I'm hopeful the 
> auto-tuner extender can extend my range a bit on either side.  It may 
> be stretching it, but I'm hoping that it can get me down to the CW 
> portion of 80 meters for this weekend's NAQP CW contest.
>
> It would be nice too if the extender could help me tune the DXCC on 30 
> meters, but that also remains to be seen.
>
> Anyway, one of this week's projects will involve getting the unit set 
> up and tested.
>
> But, I have a question.
>
> In the manual, it says that you should connect a dummy load and an RF 
> ground to the tuner extender, to ensure protection of your rig.  I 
> understand the reasoning behind the RF ground, and will make up that 
> connection, as I do for any of my station equipment.  However, the 
> need for a dummy load for rig protection is not totally clear to me in
this case.
>
> Here's what the manual says:
>
> "The MFJ-914 connects in-line between your transmitter and antenna.
> Connect your transmitters antenna output to the SO-239 connector 
> labeled Transmitter, and your antenna to the Antenna connector. For 
> maximum protection of your tranceiver, a 50 Ohm dummy load should be 
> connected to the plug labeled Dummy Load, and the Ground stud 
> connected to a good RF ground."
>
>
> My original plan was to work with the auto-tuner extender on low 
> power, say
> 10 or 20 watts, and then increase the output power to 100 watts before 
> any qsos on the needed bands.
>
> Am I on relatively firm ground here?
>
> Tom Behler: KB8TYJ
>
>