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KX1: requesting recommended wire antenna lengths advice

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Pat Ring

KX1: requesting recommended wire antenna lengths advice

Hello. I researched this, eh, pretty thoroughly, but I keep running into a
little problem with the recommended lengths for direct-fed antennas. The
KXATU guides recommend a 24'-28' radiator and a 1/8 wave
ground/counterpoise, but I have seen 28' and 41' recommended as well (some
with recommended radials and some without). The 24' wire tuned up fine on
20m and 30m, around 1.2:1, but I can't get an KX1ATU lower than about 8.9
SWR on 40. Am I missing something obvious, or should I continue to
experiment? I've only tried that ATU about three times on 40M because that
SWR seems pretty high to me and has to be tough on the kit. I am reluctant
to continue to try anything in this range now. I don't really want to take
coax on the road with me, and 20m and 30m are ok, but I would like to
participate in the 4sQRP on 40m when I am on the road this week. I would
appreciate your advice. Thanks. Pat NQ0N
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k6dgw

Re: KX1: requesting recommended wire antenna lengths advice

I made mine from 24' of RG-58 with a BNC on one end, Pat. I left about
3 in of outer covering, and then stripped all the rest off. If you
spread the braid some down by the connector, you can pull a loop of the
inner conductor through it and pull it out. The "radiator" is just
under 24 ft, the braid, when pulled tight is about 26 ft. I hang the
radiator in a tree and stretch the braid out on the ground. Tunes fine
on 40, 30, and 20 with the KXAT1.

40 meters is a semi-tough band for 3W, dead in the daytime and fairly
noisy at night. 30 seems to be a much better choice.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 50th Running of the Cal QSO Party 3-4 Oct 2015
- www.cqp.org

On 4/19/2015 3:08 PM, Pat Ring wrote:

> Hello. I researched this, eh, pretty thoroughly, but I keep running into a
> little problem with the recommended lengths for direct-fed antennas. The
> KXATU guides recommend a 24'-28' radiator and a 1/8 wave
> ground/counterpoise, but I have seen 28' and 41' recommended as well (some
> with recommended radials and some without). The 24' wire tuned up fine on
> 20m and 30m, around 1.2:1, but I can't get an KX1ATU lower than about 8.9
> SWR on 40. Am I missing something obvious, or should I continue to
> experiment? I've only tried that ATU about three times on 40M because that
> SWR seems pretty high to me and has to be tough on the kit. I am reluctant
> to continue to try anything in this range now. I don't really want to take
> coax on the road with me, and 20m and 30m are ok, but I would like to
> participate in the 4sQRP on 40m when I am on the road this week. I would
> appreciate your advice. Thanks. Pat NQ0N

Re: KX1: requesting recommended wire antenna lengths advice

In reply to this post by Pat Ring

Pat and the List;

A few ideas:

First:
To rule out any issues with the ATU on 40M, you might try tuning on 40M into
a wattmeter with dummy load. Also, compare 40M with no ATU enabled to 40M
with the ATU enabled, using the same dummy load and wattmeter. Go over all
of the KXATU tests and diagnostics for the three bands.

Next:
Assuming 40M is working with your ATU, try alternate antenna and
counterpoise lengths. I saw somewhere using two counterpoise wires of 16
feet each and I do this. You might also add a 30 or 33 foot counterpoise to
help on 40M.

A rule-of-thumb is to avoid anything which is 1/2 wavelength or a multiple
thereof for the antenna. Half-wavelength antennas are high impedance at the
feedpoint; above the range of the ATU in the KX1. For example, 33 feet may
work well on 40M, but is a half-wavelength on 20 and would have difficulty
tuning on 20M.

I've used 40-42 feet for my radiator with two 16 foot counterpoise radials.
It seemed to avoid a half-wavelength on 30M (which would be 46.3 feet) and
worked on three bands.

These short (28 foot) wire antennas and single, short radials will work on
the three bands and the short lengths make it easy to hang from a balcony,
tree or a collapsible pole, but they are a minimum. The antenna will
perform better than a helical or center-loaded whip, but it is pretty much a
ground plane with a poor radial and antenna literature suggests that many
radials are needed for efficiency in verticals over ground. Some time, I
want to try more wire on my end-fed field antenna, possibly 80 to 100 feet
with several 16 foot radials, or, a radial for each band. That would be
more effective than 28 feet/1 radial.

I'd also like to try a doublet of 60 to 88 feet; fed with a parallel
feedline of made the same "stealth" wire as the antenna (no heavy ladder
lines). The doublet would be more cumbersome (requiring one central support
or else supports at each end). The antenna plus feeder length would be
chosen to provide a relatively tame feedpoint impedance and reactance on the
three bands; 40/30/20M.

More research is needed on end- and center-fed (no coax) wire antenna
lengths for the KX1 (and the KX3)

I agree, leave the co-ax at home!

73
Jay
W6CJ

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Pat
Ring
Sent: Sunday, April 19, 2015 15:09
To: [hidden email]
Subject: [Elecraft] KX1: requesting recommended wire antenna lengths advice

Hello. I researched this, eh, pretty thoroughly, but I keep running into a
little problem with the recommended lengths for direct-fed antennas. The
KXATU guides recommend a 24'-28' radiator and a 1/8 wave
ground/counterpoise, but I have seen 28' and 41' recommended as well (some
with recommended radials and some without). The 24' wire tuned up fine on
20m and 30m, around 1.2:1, but I can't get an KX1ATU lower than about 8.9
SWR on 40. Am I missing something obvious, or should I continue to
experiment? I've only tried that ATU about three times on 40M because that
SWR seems pretty high to me and has to be tough on the kit. I am reluctant
to continue to try anything in this range now. I don't really want to take
coax on the road with me, and 20m and 30m are ok, but I would like to
participate in the 4sQRP on 40m when I am on the road this week. I would
appreciate your advice. Thanks. Pat NQ0N
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Don Wilhelm-4

Re: KX1: requesting recommended wire antenna lengths advice

In reply to this post by Pat Ring

Pat,

The KXAT1 is optimized for the lengths shown in the manual, so I am
surprised that you are having trouble with them. OTOH, such
non-resonant antennas are sensitive as to how they are deployed.
If you continue to have trouble on 40 meters, I would suggest a 33 ft.
radiator with a 33 ft. radial. That should be close to resonance on 40
meters and provide a sufficiently low feedpoint impedance to the KXAT1.

73,
Don W3FPR

On 4/19/2015 6:08 PM, Pat Ring wrote:

Don Wilhelm-4

Re: KX1: requesting recommended wire antenna lengths advice

In reply to this post by J

My best field antenna consists of a 32 ft. heavy duty push-up
telescoping fiberglass pole which supports an inverted vee with radiator
legs 22 feet long (of #22 teflon insulated wire). The feeder is twisted
pair #22 teflon insulated wire (parallel feedline) 25 feet long.
That feedline terminates into a balun which is switchable between a 1:1
and a 4:1 ratio (a smaller homebrew version of the Elecraft BL2). I
carry a 25 foot length of coax to connect from the balun to the transceiver.
That antenna loads and works well for 40 through 10 meters - I switch
the balun from the 1:1 to the 4:1 position depending on the band in use
and the best match.

I also carry two additional lengths of #22 teflon insulated wire which I
clip onto the ends of the radiator to extend the length if I want to
operate on 80 meters.

That is my portable antenna, and it works well for me. I prefer
balanced antennas when I can use them. It is not 'backpack' eligible
because of the 32 foot pole, but then I am not doing any backpacking
these days.

I can put my antenna up in several configurations. If I have a support
for one end, I can set the antenna up as a dipole. If I only have the
fiberglass pole, I support the center of the dipole at the top of the
pole and use it as an inverted VEE (the most desirable and common
configuration). In cases where I do not have much horizontal real
estate to work with, I set it up as a vertical - the end of one radiator
wire is tied to the pole and the other radiator wire is used as a
'radial' - 10 feet of it comes down the pole (the feedline is 10 feet
above the ground), and the remainder of the 'radial' is hung on nearby
shrubs and bushes in the best manner possible.
So, three antennas in one - depending on the terrain and other available
supports.

73,
Don W3FPR

On 4/19/2015 7:31 PM, J wrote:

> I'd also like to try a doublet of 60 to 88 feet; fed with a parallel
> feedline of made the same "stealth" wire as the antenna (no heavy ladder
> lines). The doublet would be more cumbersome (requiring one central support
> or else supports at each end). The antenna plus feeder length would be
> chosen to provide a relatively tame feedpoint impedance and reactance on the
> three bands; 40/30/20M.
>
> More research is needed on end- and center-fed (no coax) wire antenna
> lengths for the KX1 (and the KX3)
>
>

w5tvw

Re: KX1: requesting recommended wire antenna lengths advice

Don:

I have done almost the same thing here on portable outings. I use a 33'
MFJ telescopic fibreglass pole. (What holds your up?
I use a 4 prong hand cultivator with a 3' shaft. Hold pole on shaft
with a couple of bungee cords. I'd like to scrounge the
arrangement you use for the homebrewed 4:1/1:1 balun.) Otherwise I opt
for the Buddipole at 9 feet as a dipole or a vertical
with two drooping radial wires. I have also used very frequently the
33' single wire vertical and a Electraft T1 tuner. (The T1
is sometimes cranky to get to tune.) Never thought about using the dual
22 guage teflon wire as a twisted pair balanced line!
Just using a vertical wire I frequently use a single radial, the length
varying depending on the band.

ALWAYS a problem is 80-30 meters. Usually done with a pair of drooping
radials and a vertical radiator consisting of 4 "Antenna arms"
(88" total) and a single 9.5 foot telescopic whip above the antenna
arms. One Buddipole loading coil at base of vertical /antenna arms
combination tuned for resonance. In many instances the trees, etc. for
Inverted V dipoles 2' fibreglass "driveway marker rods" 2 feet long.
I will try the teflon twisted pair feeder. Never thought of that. I
have some old 75 ohm receiving twin lead, good for that sort of thing,
but it is too oxidized to consider it reliable in the field!

I try to avoid the loading coils in the dipoles except for the higher
bands. Although the Buddipole works well as a dipole at 9 feet up
sometimes the vertical whip is better on 20 meters. As I said, ALWAYS a
problem at 80-30 meters to play with verticals with whips.

Good tips. All of that can be a big guess without the trusty MFJ analyzer!

73,

Sandy Blaize W5TVW

On 4/19/2015 6:58 PM, Don Wilhelm wrote:

> My best field antenna consists of a 32 ft. heavy duty push-up
> telescoping fiberglass pole which supports an inverted vee with
> radiator legs 22 feet long (of #22 teflon insulated wire). The feeder
> is twisted pair #22 teflon insulated wire (parallel feedline) 25 feet
> long.
> That feedline terminates into a balun which is switchable between a
> 1:1 and a 4:1 ratio (a smaller homebrew version of the Elecraft BL2).
> I carry a 25 foot length of coax to connect from the balun to the
> transceiver.
> That antenna loads and works well for 40 through 10 meters - I switch
> the balun from the 1:1 to the 4:1 position depending on the band in
> use and the best match.
>
> I also carry two additional lengths of #22 teflon insulated wire which
> I clip onto the ends of the radiator to extend the length if I want to
> operate on 80 meters.
>
> That is my portable antenna, and it works well for me. I prefer
> balanced antennas when I can use them. It is not 'backpack' eligible
> because of the 32 foot pole, but then I am not doing any backpacking
> these days.
>
> I can put my antenna up in several configurations. If I have a
> support for one end, I can set the antenna up as a dipole. If I only
> have the fiberglass pole, I support the center of the dipole at the
> top of the pole and use it as an inverted VEE (the most desirable and
> common configuration). In cases where I do not have much horizontal
> real estate to work with, I set it up as a vertical - the end of one
> radiator wire is tied to the pole and the other radiator wire is used
> as a 'radial' - 10 feet of it comes down the pole (the feedline is 10
> feet above the ground), and the remainder of the 'radial' is hung on
> nearby shrubs and bushes in the best manner possible.
> So, three antennas in one - depending on the terrain and other
> available supports.
>
> 73,
> Don W3FPR
>
>
> On 4/19/2015 7:31 PM, J wrote:
>> I'd also like to try a doublet of 60 to 88 feet; fed with a parallel
>> feedline of made the same "stealth" wire as the antenna (no heavy ladder
>> lines). The doublet would be more cumbersome (requiring one central
>> support
>> or else supports at each end). The antenna plus feeder length would be
>> chosen to provide a relatively tame feedpoint impedance and reactance
>> on the
>> three bands; 40/30/20M.
>>
>> More research is needed on end- and center-fed (no coax) wire antenna
>> lengths for the KX1 (and the KX3)
>>
>>
>
> ______________________________________________________________
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>
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Don Wilhelm-4

Re: KX1: requesting recommended wire antenna lengths advice

Sandy,

For the switchable balun I used the design of the Elecraft BL2 but used
the binocular core of the K2 T4 transformer to get it into a smaller
package.

I usually can find some near vertical support post for the pole. At a
campground, there are usually some vertical supports for a lightpole or
a lantern hanging post. There is always a picnic table that can offer
some support for the pole. Yes, I use bungy cords.
If you want to add something to your go-kit, add a 4 foot PVC pipe that
is cut at a 30 degree angle on one end. You can sink that into the soil
by the angled end and use that for the pole support. I also carry some
mason line that can be used as guys for the pole if no real supports are
available. When deployed as an inverted VEE, the two radiator wires can
also be used as guys, so the mason line is only needed for one (or 2
additional guys).

In other words, do what you have to as dictated by the physical
circumstances you are faced with. A little ingenuity will go a long
way, use what is available. If you are planning a trip to the beach, a
PVC pipe that can be driven into the sand to anchor the base of the pole
and 3 or 4 tent pegs to secure the mason line guys will do the trick.
In the forest of more primitive campgrounds, there are trees and shrubs
to provide anchor points for the mast and any guy wires that are required.

If you have a camper, that can provide a solid fastening for the base of
the pole, but if using a tent, you may have to use the picnic table or
other supports in the campground. Bungy cords will be a good addition
to your portable gear.

OTOH, if you are backpacking, you are not going to have the telescoping
pole, so a weighted bag to throw over a tree limb (or a rock with mason
line around it) will have to serve as your antenna launching device. It
all depends on the circumstances you are faced with at the particular
moment. I have graduated from backpacking in my older age, so I can
take more gear along with me on my portable outings.

73,
Don W3FPR

On 4/19/2015 8:58 PM, Sandy wrote:

> Don:
>
> I have done almost the same thing here on portable outings. I use a
> 33' MFJ telescopic fibreglass pole. (What holds your up?
> I use a 4 prong hand cultivator with a 3' shaft. Hold pole on shaft
> with a couple of bungee cords. I'd like to scrounge the
> arrangement you use for the homebrewed 4:1/1:1 balun.) Otherwise I
> opt for the Buddipole at 9 feet as a dipole or a vertical
> with two drooping radial wires. I have also used very frequently the
> 33' single wire vertical and a Electraft T1 tuner. (The T1
> is sometimes cranky to get to tune.) Never thought about using the
> dual 22 guage teflon wire as a twisted pair balanced line!
> Just using a vertical wire I frequently use a single radial, the
> length varying depending on the band.
>
> ALWAYS a problem is 80-30 meters. Usually done with a pair of
> drooping radials and a vertical radiator consisting of 4 "Antenna arms"
> (88" total) and a single 9.5 foot telescopic whip above the antenna
> arms. One Buddipole loading coil at base of vertical /antenna arms
> combination tuned for resonance. In many instances the trees, etc.
> for Inverted V dipoles 2' fibreglass "driveway marker rods" 2 feet long.
> I will try the teflon twisted pair feeder. Never thought of that. I
> have some old 75 ohm receiving twin lead, good for that sort of thing,
> but it is too oxidized to consider it reliable in the field!
>
> I try to avoid the loading coils in the dipoles except for the higher
> bands. Although the Buddipole works well as a dipole at 9 feet up
> sometimes the vertical whip is better on 20 meters. As I said, ALWAYS
> a problem at 80-30 meters to play with verticals with whips.
>
> Good tips. All of that can be a big guess without the trusty MFJ
> analyzer!
>
> 73,
>
> Sandy Blaize W5TVW
>
>
> On 4/19/2015 6:58 PM, Don Wilhelm wrote:
>> My best field antenna consists of a 32 ft. heavy duty push-up
>> telescoping fiberglass pole which supports an inverted vee with
>> radiator legs 22 feet long (of #22 teflon insulated wire). The
>> feeder is twisted pair #22 teflon insulated wire (parallel feedline)
>> 25 feet long.
>> That feedline terminates into a balun which is switchable between a
>> 1:1 and a 4:1 ratio (a smaller homebrew version of the Elecraft
>> BL2). I carry a 25 foot length of coax to connect from the balun to
>> the transceiver.
>> That antenna loads and works well for 40 through 10 meters - I switch
>> the balun from the 1:1 to the 4:1 position depending on the band in
>> use and the best match.
>>
>> I also carry two additional lengths of #22 teflon insulated wire
>> which I clip onto the ends of the radiator to extend the length if I
>> want to operate on 80 meters.
>>
>> That is my portable antenna, and it works well for me. I prefer
>> balanced antennas when I can use them. It is not 'backpack' eligible
>> because of the 32 foot pole, but then I am not doing any backpacking
>> these days.
>>
>> I can put my antenna up in several configurations. If I have a
>> support for one end, I can set the antenna up as a dipole. If I only
>> have the fiberglass pole, I support the center of the dipole at the
>> top of the pole and use it as an inverted VEE (the most desirable and
>> common configuration). In cases where I do not have much horizontal
>> real estate to work with, I set it up as a vertical - the end of one
>> radiator wire is tied to the pole and the other radiator wire is used
>> as a 'radial' - 10 feet of it comes down the pole (the feedline is 10
>> feet above the ground), and the remainder of the 'radial' is hung on
>> nearby shrubs and bushes in the best manner possible.
>> So, three antennas in one - depending on the terrain and other
>> available supports.
>>
>> 73,
>> Don W3FPR
>>
>>
>> On 4/19/2015 7:31 PM, J wrote:
>>> I'd also like to try a doublet of 60 to 88 feet; fed with a parallel
>>> feedline of made the same "stealth" wire as the antenna (no heavy
>>> ladder
>>> lines). The doublet would be more cumbersome (requiring one central
>>> support
>>> or else supports at each end). The antenna plus feeder length would be
>>> chosen to provide a relatively tame feedpoint impedance and
>>> reactance on the
>>> three bands; 40/30/20M.
>>>
>>> More research is needed on end- and center-fed (no coax) wire antenna
>>> lengths for the KX1 (and the KX3)
>>>
>>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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> Message delivered to [hidden email]
>

Paul Huff-3

Re: KX1: requesting recommended wire antenna lengths advice

In reply to this post by Pat Ring

Hi Don,

I have had very good success with my KX1 on 20, 30 and 40 meters with WA3WSJ’s “Bead-wire antenna” - http://wa3wsj.homestead.com/WA3WSJ_Bead-Wire_Antenna.pdf <http://wa3wsj.homestead.com/WA3WSJ_Bead-Wire_Antenna.pdf>.

It’s a 40-ft radiator with three 16-ft counterpoise wires. Depending on the circumstances and available supports I’ve deployed the radiator completely horizontally, as an inverted-L, inverted-V, inverted-U, a true vertical, and even in some indescribable shapes. I usually try to spread the counterpoise wires around the compass but they have also been hung from a balcony or even twisted together and wrapped around the base of the room walls as a single wire. The KX1’s internal ATU can usually give me a good match - better than 1.4:1 - on all three bands but there can be some situations where the match on one of the bands is worse. (Conditions found in portable setups can be very different from what you had during testing in the back yard!)

The antenna is very small, lightweight, and strong. It’s easy to deploy using a slingshot or throwing bag. The only significant change that I have made from the original design is the use of 10-pound fishing line for the leader instead of the 30-pound line that WA3WSJ suggested. That way if it does get snagged in a tree the fishing line will break long before the steel antenna wire so I can always get my antenna back down. (I’ve only had snags like that three or four times over the years but I still feel bad about leaving some fishing line up in a tree. Does anyone have a suggestion for a good biodegradable line?) I’ve often wondered if it would be better with copper wire instead of the steel wire but I’ve never tried it.

This antenna is not perfect - no antenna is! But I make contacts and have fun so that works for me.

Good luck and 73,
Paul - N8XMS

President of the NAQCC
NAQCC #675

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Michael Babineau-2

Re: KX1: requesting recommended wire antenna lengths advice

In reply to this post by Pat Ring

Pat wrote :

>The 24' wire tuned up fine on 20m and 30m, around 1.2:1, but I can't get an KX1ATU lower than about 8.9
>SWR on 40. Am I missing something obvious, or should I continue to
>experiment?

Pat :

My experience is that you need a wire longer than 24 feet to get a decent match with the KXAT1 on 40m.
Anything over about 12 feet long should match pretty well on 30m and 20m. Try 28 feet if you want to
include 40m and perhaps consider a more extensive ground.

For a ground system I use a 20 foot length of computer ribbon cable with 5 or 6 conductors.
Unzip all but about the last 3 or 4 feet and then tape it so that it doesn’t unzip further. Strip all of the conductors at the
intact end of the cable and attach them all to a banana plug. This makes routing the ground off a picnic table easy as it is
one big flat ribbon but the individual unzipped wires can then be splayed out in different directions on the ground.
I find that with more than about 5 or 6 conductors it starts to turn into a bit of a tangled mess.
If I decide I want more radials then I use two of these. Note that the Pomona BNC to banana jack adaptors will allow
two banana plugs to be connected to each terminal (i.e. 2 on the red and 2 on the black).

If you want to use a shorter wire that will fit on a 20 foot fishing pole then try a 20 ft length of twin lead (I use the lightweight
Radio Shack Indoor twinlead) with the leads at the top shorted together and soldered. Install banana plugs on both of the
leads at the bottom. For 20m and 30m you can connect both banana plugs to the centre of the KX1 BNC, giving you
a FAT 20 ft radiator. On 40m just disconnect one of the banana plugs and now you have a 40 foot radiator that is
folded in half … which is effectively a 20 foot linear loaded wire that will resonate a bit below the 40m band, but will
match quite nicely on 40m. (Think of it as half of a 40 foot long folded doublet/dipole).

I have used this configuration with a 20 foot fiberglass pole to make hundreds of 40m KX1 qsos and it works quite well and deploys quickly.

Michael VE3WMB

P.S. Trust me .. folding the wire back on itself does not result in signal cancellation. At worst your vertical will have a very slightly
asymmetric omnidirectional radiation pattern.
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Pat Ring

Re: KX1: requesting recommended wire antenna lengths advice

Thanks for all of the list and offline posts. All very helpful. I thought
the 24' length was going to be quite a compromise. Tried 28' but that
didn't help much. Will try the solutions suggested. Michael, I was
reading one of your blog posts describing your folded dipole and grounding
solutions and dismissed it initially because I didn't want to carry a
pole. Now I have a thought in mind on how to deploy without a squid or
jackite pole and will look into that when I get back (I have some cat 5
cable I will untwist). Reluctantly packed some coax, unun, and long wire
(KX3 Helper) for the trip, but will look into other solutions when I
return. I know this radio has been out for years, so I knew there would be
a bunch of expertise here to help me. Thanks. Pat NQ0N

On Mon, Apr 20, 2015 at 8:05 AM, Michael Babineau <[hidden email]>
wrote:

> Pat wrote :
>
> >The 24' wire tuned up fine on 20m and 30m, around 1.2:1, but I can't get
> an KX1ATU lower than about 8.9
> >SWR on 40. Am I missing something obvious, or should I continue to
> >experiment?
>
> Pat :
>
> My experience is that you need a wire longer than 24 feet to get a decent
> match with the KXAT1 on 40m.
> Anything over about 12 feet long should match pretty well on 30m and 20m.
> Try 28 feet if you want to
> include 40m and perhaps consider a more extensive ground.
>
> For a ground system I use a 20 foot length of computer ribbon cable with 5
> or 6 conductors.
> Unzip all but about the last 3 or 4 feet and then tape it so that it
> doesn’t unzip further. Strip all of the conductors at the
> intact end of the cable and attach them all to a banana plug. This makes
> routing the ground off a picnic table easy as it is
> one big flat ribbon but the individual unzipped wires can then be splayed
> out in different directions on the ground.
> I find that with more than about 5 or 6 conductors it starts to turn into
> a bit of a tangled mess.
> If I decide I want more radials then I use two of these. Note that the
> Pomona BNC to banana jack adaptors will allow
> two banana plugs to be connected to each terminal (i.e. 2 on the red and 2
> on the black).
>
> If you want to use a shorter wire that will fit on a 20 foot fishing pole
> then try a 20 ft length of twin lead (I use the lightweight
> Radio Shack Indoor twinlead) with the leads at the top shorted together
> and soldered. Install banana plugs on both of the
> leads at the bottom. For 20m and 30m you can connect both banana plugs to
> the centre of the KX1 BNC, giving you
> a FAT 20 ft radiator. On 40m just disconnect one of the banana plugs and
> now you have a 40 foot radiator that is
> folded in half … which is effectively a 20 foot linear loaded wire that
> will resonate a bit below the 40m band, but will
> match quite nicely on 40m. (Think of it as half of a 40 foot long folded
> doublet/dipole).
>
> I have used this configuration with a 20 foot fiberglass pole to make
> hundreds of 40m KX1 qsos and it works quite well and deploys quickly.
>
>
> Michael VE3WMB
>
> P.S. Trust me .. folding the wire back on itself does not result in signal
> cancellation. At worst your vertical will have a very slightly
> asymmetric omnidirectional radiation pattern.

Jim Bolit

Re: KX1: requesting recommended wire antenna lengths advice

The length of you coax feed line also needs to be considered.

The feed line is a "transformer" by itself.

Jim
W6AIM

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Pat Ring
Sent: Monday, April 20, 2015 10:51 AM
To: Michael Babineau
Cc: [hidden email]
Subject: Re: [Elecraft] KX1: requesting recommended wire antenna lengths advice

Thanks for all of the list and offline posts. All very helpful. I thought the 24' length was going to be quite a compromise. Tried 28' but that didn't help much. Will try the solutions suggested. Michael, I was reading one of your blog posts describing your folded dipole and grounding solutions and dismissed it initially because I didn't want to carry a pole. Now I have a thought in mind on how to deploy without a squid or jackite pole and will look into that when I get back (I have some cat 5 cable I will untwist). Reluctantly packed some coax, unun, and long wire
(KX3 Helper) for the trip, but will look into other solutions when I return. I know this radio has been out for years, so I knew there would be a bunch of expertise here to help me. Thanks. Pat NQ0N

On Mon, Apr 20, 2015 at 8:05 AM, Michael Babineau <[hidden email]>
wrote:

> Pat wrote :
>
> >The 24' wire tuned up fine on 20m and 30m, around 1.2:1, but I can't
> >get
> an KX1ATU lower than about 8.9
> >SWR on 40. Am I missing something obvious, or should I continue to
> >experiment?
>
> Pat :
>
> My experience is that you need a wire longer than 24 feet to get a
> decent match with the KXAT1 on 40m.
> Anything over about 12 feet long should match pretty well on 30m and 20m.
> Try 28 feet if you want to
> include 40m and perhaps consider a more extensive ground.
>
> For a ground system I use a 20 foot length of computer ribbon cable
> with 5 or 6 conductors.
> Unzip all but about the last 3 or 4 feet and then tape it so that it
> doesn’t unzip further. Strip all of the conductors at the intact end
> of the cable and attach them all to a banana plug. This makes routing
> the ground off a picnic table easy as it is one big flat ribbon but
> the individual unzipped wires can then be splayed out in different
> directions on the ground.
> I find that with more than about 5 or 6 conductors it starts to turn
> into a bit of a tangled mess.
> If I decide I want more radials then I use two of these. Note that the
> Pomona BNC to banana jack adaptors will allow two banana plugs to be
> connected to each terminal (i.e. 2 on the red and 2 on the black).
>
> If you want to use a shorter wire that will fit on a 20 foot fishing
> pole then try a 20 ft length of twin lead (I use the lightweight Radio
> Shack Indoor twinlead) with the leads at the top shorted together and
> soldered. Install banana plugs on both of the leads at the bottom.
> For 20m and 30m you can connect both banana plugs to the centre of the
> KX1 BNC, giving you a FAT 20 ft radiator. On 40m just disconnect one
> of the banana plugs and now you have a 40 foot radiator that is folded
> in half … which is effectively a 20 foot linear loaded wire that will
> resonate a bit below the 40m band, but will match quite nicely on 40m.
> (Think of it as half of a 40 foot long folded doublet/dipole).
>
> I have used this configuration with a 20 foot fiberglass pole to make
> hundreds of 40m KX1 qsos and it works quite well and deploys quickly.
>
>
> Michael VE3WMB
>
> P.S. Trust me .. folding the wire back on itself does not result in
> signal cancellation. At worst your vertical will have a very slightly
> asymmetric omnidirectional radiation pattern.

______________________________________________________________
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Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]

______________________________________________________________
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Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Michael Babineau-2

Re: KX1: requesting recommended wire antenna lengths advice

Pat / Jim :

The idea is that there is no coax feed line. I suggest that you connect the wires directly to the rig / ATU and forget about the unun and coax.
Because a 24/28 foot wire is non-resonant if you use coax to feed it you will incur additional loses because of the mismatch. No feed-line means no feed line losses.

Michael VE3WMB

P.S. Pat if you want a longer length wire, try 51 feet. It will load very well on 40m/20m, but it may require that you roll up a couple of feet to get below
2:1 SWR on 30m. I sometimes use this as an end-fed inverted vee or inverted-L worked against the previously mentioned ribbon cable ground. The KX1 ATU will
match this.

P.P.S. As a compromise I tried a 26 ft wire at one time and I was able to get a reasonable match on 40m, however I discovered that it is much more sensitive to how it
is deployed, as compared to the 28 foot wire and in some configurations it was hard to get a decent match.

On Apr 20, 2015, at 3:00 PM, jim <[hidden email]> wrote:

> The length of you coax feed line also needs to be considered.
>
> The feed line is a "transformer" by itself.
>
> Jim
> W6AIM
>
>
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of Pat Ring
> Sent: Monday, April 20, 2015 10:51 AM
> To: Michael Babineau
> Cc: [hidden email]
> Subject: Re: [Elecraft] KX1: requesting recommended wire antenna lengths advice
>
> Thanks for all of the list and offline posts. All very helpful. I thought the 24' length was going to be quite a compromise. Tried 28' but that didn't help much. Will try the solutions suggested. Michael, I was reading one of your blog posts describing your folded dipole and grounding solutions and dismissed it initially because I didn't want to carry a pole. Now I have a thought in mind on how to deploy without a squid or jackite pole and will look into that when I get back (I have some cat 5 cable I will untwist). Reluctantly packed some coax, unun, and long wire
> (KX3 Helper) for the trip, but will look into other solutions when I return. I know this radio has been out for years, so I knew there would be a bunch of expertise here to help me. Thanks. Pat NQ0N
>
> On Mon, Apr 20, 2015 at 8:05 AM, Michael Babineau <[hidden email]>
> wrote:
>
>> Pat wrote :
>>
>>> The 24' wire tuned up fine on 20m and 30m, around 1.2:1, but I can't
>>> get
>> an KX1ATU lower than about 8.9
>>> SWR on 40. Am I missing something obvious, or should I continue to
>>> experiment?
>>
>> Pat :
>>
>> My experience is that you need a wire longer than 24 feet to get a
>> decent match with the KXAT1 on 40m.
>> Anything over about 12 feet long should match pretty well on 30m and 20m.
>> Try 28 feet if you want to
>> include 40m and perhaps consider a more extensive ground.
>>
>> For a ground system I use a 20 foot length of computer ribbon cable
>> with 5 or 6 conductors.
>> Unzip all but about the last 3 or 4 feet and then tape it so that it
>> doesn’t unzip further. Strip all of the conductors at the intact end
>> of the cable and attach them all to a banana plug. This makes routing
>> the ground off a picnic table easy as it is one big flat ribbon but
>> the individual unzipped wires can then be splayed out in different
>> directions on the ground.
>> I find that with more than about 5 or 6 conductors it starts to turn
>> into a bit of a tangled mess.
>> If I decide I want more radials then I use two of these. Note that the
>> Pomona BNC to banana jack adaptors will allow two banana plugs to be
>> connected to each terminal (i.e. 2 on the red and 2 on the black).
>>
>> If you want to use a shorter wire that will fit on a 20 foot fishing
>> pole then try a 20 ft length of twin lead (I use the lightweight Radio
>> Shack Indoor twinlead) with the leads at the top shorted together and
>> soldered. Install banana plugs on both of the leads at the bottom.
>> For 20m and 30m you can connect both banana plugs to the centre of the
>> KX1 BNC, giving you a FAT 20 ft radiator. On 40m just disconnect one
>> of the banana plugs and now you have a 40 foot radiator that is folded
>> in half … which is effectively a 20 foot linear loaded wire that will
>> resonate a bit below the 40m band, but will match quite nicely on 40m.
>> (Think of it as half of a 40 foot long folded doublet/dipole).
>>
>> I have used this configuration with a 20 foot fiberglass pole to make
>> hundreds of 40m KX1 qsos and it works quite well and deploys quickly.
>>
>>
>> Michael VE3WMB
>>
>> P.S. Trust me .. folding the wire back on itself does not result in
>> signal cancellation. At worst your vertical will have a very slightly
>> asymmetric omnidirectional radiation pattern.
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]
>
>

Pat Ring

Re: KX1: requesting recommended wire antenna lengths advice

Thanks. I meant that I have an end fed with unun, like a par endfedz. I
know it requires a certain length of coax. I don't really want to use it,
but I know it will tune up well on 40M. I'll try the other lengths when I
get back...I am looking forward to the folded dipole. I check in and my
windows are sealed. I can't drop a line out anyway. I'll just have to
have a walk down to Bourbon Street and skip ham radio tonight. Too bad.
Thanks again everyone. Pat NQ0N

On Mon, Apr 20, 2015 at 5:53 PM, Michael Babineau <[hidden email]>
wrote:

> Pat / Jim :
>
> The idea is that there is no coax feed line. I suggest that you connect
> the wires directly to the rig / ATU and forget about the unun and coax.
> Because a 24/28 foot wire is non-resonant if you use coax to feed it you
> will incur additional loses because of the mismatch. No feed-line means no
> feed line losses.
>
> Michael VE3WMB
>
> P.S. Pat if you want a longer length wire, try 51 feet. It will load very
> well on 40m/20m, but it may require that you roll up a couple of feet to
> get below
> 2:1 SWR on 30m. I sometimes use this as an end-fed inverted vee or
> inverted-L worked against the previously mentioned ribbon cable ground.
> The KX1 ATU will
> match this.
>
> P.P.S. As a compromise I tried a 26 ft wire at one time and I was able to
> get a reasonable match on 40m, however I discovered that it is much more
> sensitive to how it
> is deployed, as compared to the 28 foot wire and in some configurations it
> was hard to get a decent match.
>
> On Apr 20, 2015, at 3:00 PM, jim <[hidden email]> wrote:
>
> > The length of you coax feed line also needs to be considered.
> >
> > The feed line is a "transformer" by itself.
> >
> > Jim
> > W6AIM
> >
> >
> >
> > -----Original Message-----
> > From: Elecraft [mailto:[hidden email]] On Behalf Of
> Pat Ring
> > Sent: Monday, April 20, 2015 10:51 AM
> > To: Michael Babineau
> > Cc: [hidden email]
> > Subject: Re: [Elecraft] KX1: requesting recommended wire antenna lengths
> advice
> >
> > Thanks for all of the list and offline posts. All very helpful. I
> thought the 24' length was going to be quite a compromise. Tried 28' but
> that didn't help much. Will try the solutions suggested. Michael, I was
> reading one of your blog posts describing your folded dipole and grounding
> solutions and dismissed it initially because I didn't want to carry a
> pole. Now I have a thought in mind on how to deploy without a squid or
> jackite pole and will look into that when I get back (I have some cat 5
> cable I will untwist). Reluctantly packed some coax, unun, and long wire
> > (KX3 Helper) for the trip, but will look into other solutions when I
> return. I know this radio has been out for years, so I knew there would be
> a bunch of expertise here to help me. Thanks. Pat NQ0N
> >
> > On Mon, Apr 20, 2015 at 8:05 AM, Michael Babineau <[hidden email]>
> > wrote:
> >
> >> Pat wrote :
> >>
> >>> The 24' wire tuned up fine on 20m and 30m, around 1.2:1, but I can't
> >>> get
> >> an KX1ATU lower than about 8.9
> >>> SWR on 40. Am I missing something obvious, or should I continue to
> >>> experiment?
> >>
> >> Pat :
> >>
> >> My experience is that you need a wire longer than 24 feet to get a
> >> decent match with the KXAT1 on 40m.
> >> Anything over about 12 feet long should match pretty well on 30m and
> 20m.
> >> Try 28 feet if you want to
> >> include 40m and perhaps consider a more extensive ground.
> >>
> >> For a ground system I use a 20 foot length of computer ribbon cable
> >> with 5 or 6 conductors.
> >> Unzip all but about the last 3 or 4 feet and then tape it so that it
> >> doesn’t unzip further. Strip all of the conductors at the intact end
> >> of the cable and attach them all to a banana plug. This makes routing
> >> the ground off a picnic table easy as it is one big flat ribbon but
> >> the individual unzipped wires can then be splayed out in different
> >> directions on the ground.
> >> I find that with more than about 5 or 6 conductors it starts to turn
> >> into a bit of a tangled mess.
> >> If I decide I want more radials then I use two of these. Note that the
> >> Pomona BNC to banana jack adaptors will allow two banana plugs to be
> >> connected to each terminal (i.e. 2 on the red and 2 on the black).
> >>
> >> If you want to use a shorter wire that will fit on a 20 foot fishing
> >> pole then try a 20 ft length of twin lead (I use the lightweight Radio
> >> Shack Indoor twinlead) with the leads at the top shorted together and
> >> soldered. Install banana plugs on both of the leads at the bottom.
> >> For 20m and 30m you can connect both banana plugs to the centre of the
> >> KX1 BNC, giving you a FAT 20 ft radiator. On 40m just disconnect one
> >> of the banana plugs and now you have a 40 foot radiator that is folded
> >> in half … which is effectively a 20 foot linear loaded wire that will
> >> resonate a bit below the 40m band, but will match quite nicely on 40m.
> >> (Think of it as half of a 40 foot long folded doublet/dipole).
> >>
> >> I have used this configuration with a 20 foot fiberglass pole to make
> >> hundreds of 40m KX1 qsos and it works quite well and deploys quickly.
> >>
> >>
> >> Michael VE3WMB
> >>
> >> P.S. Trust me .. folding the wire back on itself does not result in
> >> signal cancellation. At worst your vertical will have a very slightly
> >> asymmetric omnidirectional radiation pattern.
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
> >
> >
>
>