Jim, I mentioned relay cut-in of L's and/or C's at the base of an antenna
to help cover all of 160M. On my tuner web page I mentioned does not show
this recent update I have made at my shack, but I have a relay that shunts
out turns of my 160M coil to help me QSY to top end of 160M phone in
contests.
Another choice that I left out, if you want to QSY all the way between 1800
and 2000 kc with a limited-bandwidth antenna, is relay-cut-in-and-out of
extra length at the top of the antenna. There have been QST articles, as
well as some write-ups on this mailing list, about doing this. The
electrical voltages involved, as well as complications of remotely
controlling relays at the top of an antenna, have made this a non-choice at
my station. I'm very self-satisfied about my relays at the base of my
antenna but the complications of high-voltage relays at the top of an
antenna, is not something I've done myself.
Tim N3QE
On Tue, Feb 16, 2016 at 9:05 AM, Tim Shoppa <tshoppa@gmail.com> wrote:
> My opinions:
>
> All-band antenna tuners make a set of compromises to produce a tuner that
> fits in one box.
>
> They may not be able to handle legal limit on RTTY. Or legal limits CW/SSB
> on other bands, especially the "extreme bands" of 10M and 160M.
>
> They often have 10-turn (or more-turn) roller inductors that make it very
> slow - acutally, downright painful - to QSY between bands.
>
> They usually have very limited choice of tuner topologies, or even worse,
> they don't have the "right topology" for a given band/antenna combination.
>
> If you have the space available in your shack and need a tuner for every
> band, you want to have a tuner optimized for each band in the shack and
> relay selection for tuners. Some pictures of my setup where I have taken
> this to an extreme: http://www.trailing-edge.com/tuners.html
>
> If your only problem is that your 160M antenna is narrow band and doesn't
> cover both 1830kc and 1880kc and 1950kc, your best choice is to cut in (via
> remote relays if you are into automation) some additional L and C at the
> antenna base, as appropriate, to help you QSY between different parts of
> 160M. This will cost you way way less and be far more efficient, than
> buying an all-band tuner in the shack.
>
> Tim N3QE
>
> On Sun, Feb 14, 2016 at 9:30 PM, Jim Murray via Topband <
> topband@contesting.com> wrote:
>
>> Hello all,Would you have any recommendations for antenna tuners? Have
>> been looking at the automatics, Palstar, Mfj, LDG At-1000Proii etc.. Have
>> been using an old Dentron which doesn't have very close markings on the
>> dials and getting tired of turning and adjusting. Another option would be
>> another manual such as the At2k with more precise settings. I do quite of
>> bit of band hopping and even on 160 my Inv. L is perfect on 1.830 but
>> doesn't like going very far either up or down, hence the need for a little
>> tuner loss. The automatics look pretty appealing but would appreciate any
>> opinions from the group.Thanks
>> Jim/k2hn
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
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