Mark,
I am also using a CC 402CD at 95 ft, about 300 ft behind my house,
fed with 3/4 inch CATV hardline. I use a Drake MN2000 to tune
on SSB. Try adding some coax to find a 'better' impedance range
for your tuner. I would start with around 1/4 WL of RG59.
K7LXC recommends tuning the 402CD between the CW and Mid settings.
Tom N4KG
On Wed, 2 Oct 2002 08:04:16 -0400 "Mark Pride" <mpride@us.ibm.com>
writes:
> 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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