Would you be so kind as to post the question to Don . I have
difficulty getting on Yahoo groops. thanks John kb2huk
On 8/15/2010 9:54 PM, Richards wrote:
> I also have a 43 foot monopole antenna (with 63 radials - but I agree
> 45 radials at 45 feet each is a good base.)
>
> I would suspect the balun / un-un you might be using. I know both
> ArraySolutions - Zero-5 modified the balun - un-un they supply with
> their big stick, and DX-Engineering also changed from a current balun
> (which was OK) to an un-un design (which is claimed to be better).
>
> I can tune 160, but it is all the tuner can do to do that.
>
> DX-Engineering says (although I have some doubts, as does my aerospace
> EE Elmer....) that you can get a better match on 160 if you have
> something like 150-190 feet of coax (depending on the coax type and
> velocity factor, etc) as this makes some sort of tuning stub. My elmer
> thinks not... but I know Collins used to ship an amp with an extended
> coax patch cable to insert into the line for just such an occasion.
>
> I know DX-Engineering does not add a ground to its antenna - other than
> grounding the coax on its way into the shack (as is de riggeure for
> antenna installations.) Perhaps you could try it without the ground at
> the antenna end and see if it matters - on a nice sunny day, of course !
>
> My research and experience with my big stick tells me it is VERY
> difficult to tune these antennas on 160 - and I consider every contact
> on that band just plain gravy - a bonus, as it were.
>
> Bill Salas has written several articles for QST and publishes them on a
> web site dealing with the difficulties tuning these big sticks on 160
> and 80 meters - to the end that he has developed a relatively simple and
> straightforward heavy duty matching network to add (switchable remotely
> by relays...) when working the top two bands. I am seriously
> considering adding these into the mix. I forget his call, but look for
> him on the internet, as he is well read and well regarded on the topic.
> I think he has authored two or three articles on the topic in QST this
> year, alone.
>
> ALSO... adding a capacity hat (like 45 feet of wire) to top-load the
> big stick seems like a very worthy thing to try. My research tells me
> that can substantially help in matching the stick to the rig.
>
> I would ask Palstar bout it... and also the AT-AUTO discussion group on
> Yahoo-groups as Don, the engineer who designed it and who wrote the
> software code for it, posts there daily. If you cannot or don't joint
> for some reason, I can post the question for you.
>
> Happy trails.
>
> ============================= K8JHR ============================
>
>
> \
> On 8/15/2010 8:03 PM, John Molenda wrote:
>> Hi All , I have a TT Orion II and when I use it on 160 with a palstar
>> auto tuner , TT Titan III 417Amp and a new zero five vertical antenna
>> The swr runs a muck. This only happens with 250 watts or more , the swr
>> will read on the radio or tuner say 3.1:1 the Palstar auto tuner
>> knocks it down to 1:1 and all is fine then all of a sudden maybe in the
>> middle of a qso the swr will rise to 3 .1:1and I have to re tune and of
>> course this will send the amp into a fault position . It is almost like
>> the tuner just stops working . I can't remember if this has happened on
>> other bands but it will happen on 160 . to answer some questions , no
>> the tuner in the OII is not on when I use the palstar tuner . And Yes I
>> have 48 radials down at 45 foot each. I use no grounding inside the
>> shack but my antennas and coax are grounded outside the shack . Is the
>> problem the radio , tuner , amp or what .And by the way the antenna
>> plays real nice on all other bands . thanks for your input in advance
>> . all the best ! John kb2huk
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