Will keep that suggestion in mind, John.

As I said in my previous post, the antenna really does quite well on 2
meters;  it's just 440 that seems to be the problem.  Fortunately, most of
the repeater activity in our area is on 2 meters, with very little on 440.
But, it'd be nice to get this issue with 440 resolved at some point.  It
just depends on whether I can get the help here to do it, and can get
someone brave enough to climb onto my very steep roof here.

The guy who originally put the antenna up there is very hard to get hold of
these days, but I can try that route as well.

Tom Behler: KB8TYJ


-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of John Miller
Sent: Saturday, May 17, 2014 6:46 PM
To: [log in to unmask]
Subject: Re: Question on interpreting TW2 Readings with TMV71A At Home QTH

I used to have the diamond X200, sold it when I move and wish I could afford
another one but as I recall, there wasn't much adjustment in it. The one
thing you might check though is where the 2 halves join, make sure, very
sure, you got the rod out of the center of the fiberglass enough to get to
the Phillips screw in the coupler and slid it over the shaft that sticks out
of the other half of the antenna and tightened it down. A lot of people miss
that coupler and just put the fiberglass halves together and it can tend to
cause funny stuff to happen. Other than that though there really isn't much
adjustment and mine, and the ones people in one of the clubs I belong to,
fell right in where they should when put together as I described there and
play great.
----- Original Message -----
From: "Tom Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, May 17, 2014 1:42 PM
Subject: Question on interpreting TW2 Readings with TMV71A At Home QTH


> Hi, all.
>
>
>
> Well, I was out at the RV camp site briefly yesterday afternoon, and 
> re-tested my TMV71A out there with the dual-band mobile antenna that 
> is now attached to the RV, and using my TW2 to take the needed 
> readings.
>
>
>
> Now that I've learned how to do the TW2 band switching properly, I'm 
> happy to report that the readings out there look good, and make perfect
sense.
> SWR's on both 2 meters and 440 are no higher than 1.2 to 1, and the 
> output power readings on both bands are in line with what I'd expect 
> for the TMV71A.
>
>
>
> However, I still think I might have an issue with my Diamond X200A 
> antenna that is mounted on the roof here at the home QTH, especially 
> on 440.  The antenna is near the peak of the roof, up about 40 feet or 
> so, and is fed by
> RG9913 coax.
>
>
>
> Here are some readings I get with the TMV71A, and my TW2:
>
>
>
> 2-meters on 146.47 MHZ simplex:
>
>
>
> SWR = 1.2 to 1;  Forward Power = 41 watts;  Reflected Power = 0.6 watts.
>
>
>
> Not too bad in my opinion.
>
>
>
> 440 on our local repeater frequency of 443.900:
>
>
>
> SWR = 2.4 to 1;  Forward Power = 30 watts;  Reflected Power = 5 watts.
>
>
>
> I'd be interested in anyone's thoughts as to what these readings are 
> telling me.  Although not terrible, my SWR and power readings on 440 
> are not what I'd like them to be, and I suspect that the lower forward 
> power readings are due at least somewhat to the fact that the TMV71A 
> may be folding back a bit due to the 2.4 to 1 SWR.  I'm not exactly 
> sure how to re-tune the Diamond X200A for 440 to allow it to perform 
> better, and certainly don't want to get someone to climb up on the 
> roof with an antenna analyzer to help until I have a very good idea as 
> to what adjustments need to be made.
>
>
>
> In the meantime, I guess I'm fortunate in that the only 440 repeater in 
> our
> local area is about a mile from my house, and can be hit easily with 5
> watts.
>
>
>
> Part of me just says:  "If it ain't broken, don't try to fix it.";  but 
> the
> slightly elevated SWR on 440 does concern me a bit.
>
>
>
> Tom Behler: KB8TYJ
>
>
>
>