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Charles . . .

On Sun, 19 Jan 2025 05:36:29 -0800, "CRY42 via groups.io"
<cy122042@...> wrote:

I purchased the 1898 collapsible antenna which came with no directions.

I looked on their website for directions and that product apparently doesn't
come with any directions. Most of their products did come with directions that
you could download from their website if they weren't in print form in the box
or package.

Do you have any tuning suggestions, I find it a bit touchy to tune.
Or have you worked out a Tuning Chart for the bands as to how to set the lower and upper sections

Perhaps someone else here who has one of those or has one of the similar
antennas sold under different names, but looking at what you bought, it looks
like you extend the telescoping part on top, then find a tap on the coil by
moving the silver metal part on the bottom out or in at the bottom, where you
get a low SWR reading on the low end of the band, then fine tune by shortening
the whip section. (I think I have that in the right direction, because shorter
means higher frequency.) It appears that there might be a coil inside and when
you move the bottom part down and away from the top, you are selecting a coil
tap. In essence, I think you are shorting out turns using the bottom silver
metal part by moving it into or partially out of the black coated section.
That's my best guess, so if I'm wrong, some of this may not apply.

You didn't say what radio you were working with, but if it has a built-in tuner,
you will probably have to use it if you change frequency in the same band. But
before using the tuner, I would bypass the tuner and get the SWR under 2:1, then
let the tuner do its thing. If you don't have a built-in tuner, you will
probably want one (or need one). I like an auto-tuner like the MFJ-993B but
their Versa Tuner II with the cross-needle SWR meter works well, too. It just
isn't automatic.

You will probably have to work out a tuning chart, but you are on the right
track. Since the antenna came with no directions, you will need a ground of some
sort, at least one wire up to or longer than a 1/4 wavelength on the lowest band
you will be operating on. So for 40M, somewhere around 33-35 feet or so. Ideally
(and this isn't an ideal antenna, of course), you would want several radials,
but this is an antenna for portable operation and we don't want to make this
difficult to set up, so one or two wires as a counterpoise for your ground,
connected to the ground of your tuner or radio, but it would be best to connect
it where the coax connects to the antenna.

You don't get anything to mount the antenna on, so you'll need something for
that. Maybe something like this:



Sorry, but when I shortened the link it didn't work. :-)

Then you would connect your counterpoise to the copper part of the ground mount
above. (I just ordered one of these ground mounts from MFJ. They apparently
still have some, along with some other goodies, some of which are factory
seconds.)

Here are three videos that might be of some help.







Maybe you can see how the presenters used their 1898. Keep in mind that a low
SWR does not mean your antenna is efficient. A dummy load is close to zero
efficiency yet it has a near perfect 1:1 SWR! Also, as ground losses mount (less
radials, dry, rocky ground, etc.), SWR may improve but efficiency can be very
low.

If you don't get what information you need here, try out our ham-antennas group
or the HamRadioHelp group.


(antennas, feedlines, anything related to antennas like tuners, etc.)


(general purpose amateur radio discussion group)


Donald KX8K








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