Hi Christy.
I don't think that I personally would try to take apart the mag mount and
change out the coax--I'd probably just get one of the coaxial barrel
connectors and just join a suitable lengthof coax with connectors onto what
you already have. True, coax connectors are a little lossy at UHF, but
probably not that terrible. Also, I have to comment that not all dual band
antennas work really efficiently on both bands. Admittedly, it's usually 2
meters where you find the compromises, but not always. What would make an
interesting test would be if you could just get a 1/4 wave element for 2
meters and unscrew the other element--I'd ask around and see if you can
borrow one before going out and buying one. A 1/4 wave on 2 meters will be
close enough to a 3/4 wave on 70 cm to give you some performance, though
not as good as a resonant antenna. Still, if you start hitting repeaters,
that would be a pretty good indicator that something is drastically wrong
with that antenna. The beauty of the 1/4 wave idea is that it is such a
simple antenna that there isn't much to go wrong, so it takes a lot of the
guesswork out of what might be happening with the antenna.
The other thing you could do is ask around and see if anyone has an antenna
analyzer and a few minutes to sweep the antenna on the filing cabinet and
see what it looks like in terms of SWR and more importantly, impedance. I
have an MFJ one that goes up to UHF that I got just so when friends come
over to help me work on antennas, I have decent instrumentation. I realize
those kiddos are too pricy since they are somewhat more expensive than the
talking SWR bridges that someone was talking about, but perhaps if you talk
it up a bit, you can find someone that has one. I'd be surprised if
someone didn't have one and more surprised if the hams in your area were
unwilling to lend a hand.
73, de Lou K2LKK
At 07:19 PM 1/18/2007 -0600, you wrote:
>I don't even remember the model, it's a dual band, brand new magmount I got
>from Ebay. The cable running from it isn't all that long, so moving it isn't
>really much of an option. right now it's sitting on top of a metal filing
>cabinet, which is on top of a small dining room table, so the bottom of the
>antenna is perhaps four and a half feet off the ground. It's also directly
>by a window, not sure if that helps or not but figured it can't hurt anyway.
>I have neither the tools nor the knowledge to extend the cabling on it, or
>I'd probably find some kind of way to get it even higher, and out of easy
>cat reach. Unfortunately I don't have the cash to drop on the talking
>meters, though that's a future plan for sure. Anyway, for now i'll just stay
>off 440, my next project, probably even before getting an HF rig, is getting
>an accessible HT. Actually two, since I'm hoping my roommate will get her
>license soon.
>
>
>
>-----Original Message-----
>From: For blind ham radio operators
>[mailto:[log in to unmask]]On Behalf Of Louis Kim Kline
>Sent: Thursday, January 18, 2007 5:52 PM
>To: [log in to unmask]
>Subject: Re: Handihams, was: RE: exam
>
>
>Hi.
>
>That's why I asked what antenna she is running--it doesn't square with my
>experience either, suggesting that maybe she is using a design that is a
>poor radiator on 440.
>
>73, de Lou K2LKK
>
>
>
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Louis Kim Kline
A.R.S. K2LKK
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Work Telephone: (585) 697-5753
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