Matt,
If this is a open wire feed antenna you wouldn't want to make a feed
line choke out of the openwire. If you had enough extra coax, you could
wind one in the coax at the balun, although I doubt it would really
help with your need to get more coverage on 80 meters.
I still think an e-mail to the guy who builds this thing in New England
may help. I understand he is pretty responsive. He may tell you to
go ahead and get a tuner, or perhaps tweak the feedline length to get
what you want.
Perhaps a ham friend has an external tuner he can bring over and you can
see how it does in your situation. This is a pretty short antenna, and
you may have to give up the top of the band to get the bottom.
Another thought is an MFJ tuner extender, which goes into the feedline
at the radio and has a knob that changes some value to make the
internal tuner see a better situation down the feedline. I forget
if it adds inductance, or capiticance, or whatever. Some on the list
have had success with this unit, others not so much.
I've been running an MFJ 998 high power auto tuner for about 8 years
with no problems with up to a kw output.
73, Steve KW3A.
On 5/4/2015 9:23 AM, Matthew Chao wrote:
> Hi, Steve. Am using an UltraLight (forgive the spelling) Junior with
> a 4-1 balun. Would try to make an RF choke out of the feedline, but
> barely have enough for a little bit of slack to account for wind. No
> problems from about 3.8 up; it's below that where I have a
> problem. Aside from that, everything from 3.8 or so and up seems to
> work fine. Sure, I could probably get a tuner to get closer matches,
> but not sure if it's worth the money.--Matt, N1IBB.
>
> At 02:43 PM 5/3/2015 -0400, you wrote:
>> Matt,
>>
>> Nothing wrong with an external tuner. It will probably have a better
>> matching range than the internal tuner, but isn't magic. Maybe contact
>> the antenna builder and get his advice. Perhaps some tweaking of the
>> antenna or feedline can save you the cost of a tuner.
>>
>> Do the other bands tune to your liking? Are you trying to go from
>> 3.5 to 4.0 mhz? It may be a lot to ask of a 73 foot antenna, no matter
>> what tuner is used.
>>
>> Good luck, Steve KW3A
>>
>> On 5/3/2015 12:28 PM, Matthew Chao wrote:
>>> Hi, Folks. I have a TS480SAT which has a built-in auto tuner. Had
>>> one of my ham buddies come over and test the setup he and his buddies
>>> put up, an UltraLight Junior dipole strung between two trees and my
>>> house. We noticed that on 3.550MHZ, we were getting 4-1 SWr, egen
>>> though the antenna can go down that far - 80-10 meters. Above
>>> 3.8MHZ, the antenna tunes up.
>>>
>>> My question is: if I buy an external auto tuner, will I have more
>>> flexibility in getting a match. Are the the built-in tuners mor
>>> limited than the external ones? And what accessible tuner would you
>>> recommend if there is a difference?Thanks in advance.--Matt, N1IBB.
>>>
>>>
>>>
>
>
>
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