Dug out my trusty link coupled transmatch that is made excusively for twin
lead and pressed it into service. Have found another tap that give me less
sharp tuning range for 75 and 80 meters....now to find something for 6
meters.
Will probably take the ten tec 238a and a couple of LDG auto tuners to the
Yakima hamfest in the morning and see if can do some horse trading.
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Friday, April 11, 2008 2:27 PM
Subject: Re: [TenTec] Ten Tec 238A settings?
> Denton,
> Your observations on 80 meters and 75 is indicative of a matching
> variation across those bands, not at all abnormal for ANY tuner at those
> bands under a mismatch condition. Your antenna is not resonant likely
> at either 75 or 80m at that elevation.
>
> You did not list another important ingredient to the ANTENNA SYSTEM, the
> length of the 600 ohm feeder, and then the length of the coax post the
> balun. If either of these set up a quarter wave resonance or odd
> multiple of quarter wave at bands where the SWR is higher, you would
> have to add a few feet of feeder to give the tuner a better impedance to
> match.
>
> The surrounding terrain, and local earth character as to RF conductivity
> can also affect a large antenna.
> Check out the other factors, and remember everything from the tuner to
> the antenna makes up the Antenna System, and must be compatible with the
> band in use.
>
> 30 meters and 17 meters are not even multiples of the lower bands and
> thus are perhaps always the worst to match on a multiband antenna.
>
> -Stuart
> K5KVH
>
>
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>
>
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