Can you change the length of the elements? I think that CW would be onger
than SSB so if you can shorten the elements would that not work? GURUs?
Chris opr VE7HCB
At 08:04 AM 2002-10-02 -0400, Mark Pride wrote:
>Fellow TTer's: Problem - Have a 2 element yagi on 40 M that is currently
>tuned for the CW end of the band. In order to use it on the SSB end, past
>techniques have included locating a Transmatch at the base of the tower and
>adjusting the match so the amplifier can tune properly - this has proved
>difficult as it was inconvenient to re-tune for other portions of the phone
>band (tower base is 300 ft. from the shack and the bandwidth with the tuner
>was not too great); another approach used was to locate the tuner in the
>shack - made it convenient to re-adjust as necessary, but caused severe
>voltage breakdown conditions on the feed line (high SWR plus the amplifier
>proved disasterous for connectors).
>
>What are others doing to make the SWR better on the opposite end of the
>band the antenna was originally tuned? Have considered adding stubs
>somewhere on the feedline, but have not tried as yet. Looking for a way to
>allow the amplifier to tune properly across the entire phone band even
>though the antenna's performance is degraded due to a non-optimzed setting
>of the elements for that part of the band. 40 M phone is not my favorite
>but with this problem fixed, I can at least make a better score in those DX
>contests. (That's the plan anyway!)
>
>I realize this is transmission line theory 101, but thought there might be
>a quick answer out there!
>
>The yagi is a Cushcraft 402 at 100 ft. fed with 3/4 - inch diameter 75 ohm
>hardline (300 ft. plus 100 ft. up tower).
>
>Regards,
>
>Mark, K1RX
>
>
>
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