Re: matching 6 m 2 element Yagi
thanks Dave. In fact I rather don't know, what I am doing. I just did not want to get an antenna off the shelf and do something homebrew and the DK7ZB conzept looked easy. But hen on the first setup something did not match as predicted so I suspected the? matching stup so I wanted to measure it. Up to now I only have used the NVNA to trimm antennas to resonance.
?
Martin
DK3UW
|
PALM RADIO paddle & straight key SOLD
Groups,? I've sold my PALM RADIO straight key and paddle. Thanks everyone for your interest and patience
73 Jay W6CJ
|
Re: AX1 - Collapsible Whips
It must be stainless steel because I have left it outside in the rain many times and there is no rust. ? Paul ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Brian KB9BVN via groups.io
Sent: Wednesday, March 26, 2025 3:10 PM
To: [email protected]
Subject: Re: [qrparci] AX1 - Collapsible Whips? Paul is that 25 footer stainless steel?
de KB9BVN
Brian
On 3/26/2025 12:47 PM, Paul Quillen N4LCD via groups.io wrote: Chameleon also has a 25¡¯ extendable whip for $100. Also available at DX Engineering with free shipping due to price. Very well built. ? ? ? The Chameleon whips are built pretty well at the bottom. The early MFJ whips were quite fragile, but the later ones were much better. The Chameleons are still built better than the MFJ items..............
73 de Lee KX4TT On Tuesday, March 25, 2025 at 06:39:40 PM EDT, MIKE N6ZW via groups.io <n6zw@...> wrote: Those are the same that MFJ used to sell before they went closed their doors. I use one for several HB antennas and it works very well alone. You can even base load one easily.? 73,? Mike n6zw On 03/25/2025 3:28 PM PDT Dave AB7E via groups.io <ab7echo@...> wrote:
I forgot to include the link to the SS17 whip:
The pictures in the first review are mine (Alice is my wife's name).
Dave? AB7E
-------- Forwarded Message --------
Except that the AX1 isn't enough of a vertical to actually act like a short vertical.? If you model an AX1 and look at the current distribution you will see that most of it is in the counterpoise wire.? To be honest, the AX1 whip is mostly a convenient lossy tank circuit to act as a counterpoise for the counterpoise wire ... or in some case, the shield of the coax feedline.
I know how to use EZNEC.? I've used it continually since 1993 or so when it was still called ELNEC, and I'm actually a big fan of vertical antennas for portable operation.? My choice, though, is the Chameleon SS17 collapsible whip with elevated radials.? My version weighs about 3.5 pounds ... with steel stakes ... and I can set it up in less than ten minutes.
An an end fed wire doesn't have to be very far off the ground to avoid being a worm warmer.? Why do you think elevated radials work when they are only a foot or two off the ground??? I'm not actually a big fan of end fed wire antennas, but for portable use I don't think they can be beat for performance, size, weight, or cost.? I wish I had an AX1 to compare against various alternatives using WSPR, but I'm not willing to spend the money on one just to prove ... or disprove, if that should be the case ... my point.? Curiously, almost nobody who owns an AX1 has bothered to do a similarly rigorous A-vs-B comparison either.? Presumably, like you, they don't really care as long as "it works".
Dave?? AB7E
On 3/25/2025 2:44 PM, Dan N7CQR via groups.io wrote: I¡¯ve used this strategy on bare summits above 3-4000 feet with some success. Unfortunately at sea level or low elevation you¡¯re just warming the earthworms. Any type of short vertical with an elevated radial will provide a decent takeoff angle. You can model this in EZNEC. A good resource for using short verticals effectively are the writings of Jerry Severns for the ARRL Antenna handbook or the website for antenna ¡®guru¡¯ LB Cebik.?
On Mar 25, 2025, at 12:42, Dave AB7E via groups.io <AB7Echo@...> wrote:
You should try the EFRW sometime just laying on the ground, or maybe laying across a rock.? I'll say again ... most of the radiating from an AX1 comes from either the counterpoise or the shield of the coax (if not using a common mode choke), and for the majority of uses either of those are lying on or very near the top of the ground.? The surface of most "ground" isn't an RF ground, and if the soil is dry or fairly non-conductive the actual RF ground is probably several feet below the surface.? Not sure what the ground characteristic in the Orkneys is, though.
Dave?? AB7E
On 3/25/2025 12:18 PM, Dan N7CQR via groups.io wrote: I forgot to mention that I also carry a EFRW in my little bag,that of course is more efficient than almost short loaded vertical. Mine is Adam¡¯s K6ARK clever design that incorporates a 9:1 balun into the BNC connector. But you have to have either a tree or a pole to toss it into. If you¡¯ve been to the Orkneys you know that there¡¯s not many trees there¡?
On Mar 25, 2025, at 11:22, Dan N7CQR via groups.io <N7CQR@...> wrote:
It¡¯s a matter of trade offs that each operator is willing to make. No doubt that other larger antennas can be more efficient,but how much are you willing to pack around? Last summer I made a trip to the Orkney Islands,and you are definitely limited in how much baggage you can bring on a very small plane. . Wanting to get some radio time in,it¡¯s an easy decision to bring my small bag and still have room for clothing and other essentials. And I successfully got on the air with the AX1 at 5W. Worked 10 countries in one 45 minute session. For me that¡¯s a good trade off. ?Back home I use the best antenna I can reasonably carry. Lately I¡¯ve been using the Chelegance MC 750 vertical which is a full 1/4 wave on 20-10 Meters with the KH1 and having excellent results. It breaks down into a relatively small package-but still nothing I¡¯d ever fly or take a longer hike with. We have so many great options these days.?
?
--
72 de KB9BVN
|
?? FS: PALM RADIO paddle & straight key
Groups, I'm selling my Palm Radio paddle key and straight key. Both are in good condition.   They were used on a few stealth QRP hotel stays, and then retired. Palm Radio in Germany (Dieter Engels, DJ6TE) closed shop in 2018, so these are rare....I even saw a guy on e-pay trying to sell one for $750!
I'm asking $120 for both, which includes the cost of shipping to a USA address. Terms:? Paypal Family & Friends or personal check.?? Pre-owned, no returns.
Thanks & 73, Jay W6CJ
|
Re: AX1 - Collapsible Whips
Paul is that 25 footer stainless steel?
de KB9BVN
Brian
On 3/26/2025 12:47 PM, Paul Quillen
N4LCD via groups.io wrote:
toggle quoted message
Show quoted text
Chameleon also has a 25¡¯ extendable whip
for $100.
Also available at DX Engineering with free
shipping due to price.
Very well built.
?
?
?
The Chameleon whips are built pretty well
at the bottom. The early MFJ whips were quite fragile, but
the later ones were much better. The Chameleons are still
built better than the MFJ items..............
73 de Lee KX4TT
On
Tuesday, March 25, 2025 at 06:39:40 PM EDT, MIKE N6ZW
via groups.io <n6zw@...>
wrote:
Those
are the same that MFJ used to sell before they
went closed their doors. I use one for several
HB antennas and it works very well alone. You
can even base load one easily.? 73,? Mike n6zw
On
03/25/2025 3:28 PM PDT Dave AB7E via groups.io
<ab7echo@...>
wrote:
I
forgot to include the link to the SS17 whip:
The pictures in the first review are mine
(Alice is my wife's name).
Dave? AB7E
-------- Forwarded Message --------
Except
that the AX1 isn't enough of a vertical to
actually act like a short vertical.? If you
model an AX1 and look at the current
distribution you will see that most of it is
in the counterpoise wire.? To be honest, the
AX1 whip is mostly a convenient lossy tank
circuit to act as a counterpoise for the
counterpoise wire ... or in some case, the
shield of the coax feedline.
I know how to use EZNEC.? I've used it
continually since 1993 or so when it was still
called ELNEC, and I'm actually a big fan of
vertical antennas for portable operation.? My
choice, though, is the Chameleon SS17
collapsible whip with elevated radials.? My
version weighs about 3.5 pounds ... with steel
stakes ... and I can set it up in less than
ten minutes.
An an end fed wire doesn't have to be very far
off the ground to avoid being a worm warmer.?
Why do you think elevated radials work when
they are only a foot or two off the ground???
I'm not actually a big fan of end fed wire
antennas, but for portable use I don't think
they can be beat for performance, size,
weight, or cost.? I wish I had an AX1 to
compare against various alternatives using
WSPR, but I'm not willing to spend the money
on one just to prove ... or disprove, if that
should be the case ... my point.? Curiously,
almost nobody who owns an AX1 has bothered to
do a similarly rigorous A-vs-B comparison
either.? Presumably, like you, they don't
really care as long as "it works".
Dave?? AB7E
On
3/25/2025 2:44 PM, Dan N7CQR via groups.io
wrote:
I¡¯ve
used this strategy on bare summits above
3-4000 feet with some success. Unfortunately
at sea level or low elevation you¡¯re just
warming the earthworms. Any type of short
vertical with an elevated radial will
provide a decent takeoff angle. You can
model this in EZNEC. A good resource for
using short verticals effectively are the
writings of Jerry Severns for the ARRL
Antenna handbook or the website for antenna
¡®guru¡¯ LB Cebik.?
On
Mar 25, 2025, at 12:42, Dave AB7E via
groups.io <AB7Echo@...>
wrote:
You
should try the EFRW sometime just laying
on the ground, or maybe laying across a
rock.? I'll say again ... most of the
radiating from an AX1 comes from either
the counterpoise or the shield of the
coax (if not using a common mode choke),
and for the majority of uses either of
those are lying on or very near the top
of the ground.? The surface of most
"ground" isn't an RF ground, and if the
soil is dry or fairly non-conductive the
actual RF ground is probably several
feet below the surface.? Not sure what
the ground characteristic in the Orkneys
is, though.
Dave??
AB7E
On
3/25/2025 12:18 PM, Dan N7CQR via
groups.io wrote:
I
forgot to mention that I also carry a
EFRW in my little bag,that of course
is more efficient than almost short
loaded vertical. Mine is Adam¡¯s K6ARK
clever design that incorporates a 9:1
balun into the BNC connector. But you
have to have either a tree or a pole
to toss it into. If you¡¯ve been to the
Orkneys you know that there¡¯s not many
trees there¡?
On
Mar 25, 2025, at 11:22, Dan N7CQR
via groups.io <N7CQR@...>
wrote:
It¡¯s
a matter of trade offs that each
operator is willing to make. No
doubt that other larger antennas
can be more efficient,but how much
are you willing to pack around?
Last summer I made a trip to the
Orkney Islands,and you are
definitely limited in how much
baggage you can bring on a very
small plane. . Wanting to get some
radio time in,it¡¯s an easy
decision to bring my small bag and
still have room for clothing and
other essentials. And I
successfully got on the air with
the AX1 at 5W. Worked 10 countries
in one 45 minute session. For me
that¡¯s a good trade off. ?Back
home I use the best antenna I can
reasonably carry. Lately I¡¯ve been
using the Chelegance MC 750
vertical which is a full 1/4 wave
on 20-10 Meters with the KH1 and
having excellent results. It
breaks down into a relatively
small package-but still nothing
I¡¯d ever fly or take a longer hike
with. We have so many great
options these days.?
--
72 de KB9BVN
|
Re: matching 6 m 2 element Yagi
Personally, I don't think an SWR of 1.4 will give you much problem,
but you might consider using NanoVNASaver (free application) with
your VNA to sweep the frequency from, say, 30 to 60 MHz and save the
result as a Touchstone file (.s1p format).? It is VERY easily done,
and then you can use Zplots by AC6LA (also free) to read that
Touchstone file to plot almost any parameter you want as a function
of frequency ... including resistance and reactance.? It might help
your investigation.
Keep in mind that the reactance of a resistor doesn't change with
frequency, whereas the reactance of the driven element of the
antenna will.? The resistor will only be accurate at (in your case)
37.8 MHz.?
Also, it takes very little difference in the length of a 1/4 wave
stub to make a difference in its transformation.? You obviously know
what you're doing so I'm sure that you are aware that it is a
hyperbolic function in form ... and it will transform BOTH
resistance and reactance.? You could possibly be off just a little
in the physical length or in the estimate of 0.63 for velocity
factor.? I just did a bit of playing around with TLW, the free
transmission line application, and at 50 MHz a difference of only
0.5 inches in length of RG-6 coax changes the reactance of
the input of a quarter wave transmission line terminated in 28 ohms
by 10 ohms.? A difference in velocity factor between 0.63 and 0.64
would also be about 0.5 inches for a quarter wavelength at 50 MHz.
Once you build the antenna, you could probably bring the resonance
almost exactly to the frequency you want by using some sliding
sections of dielectric (like nylon or HDPE).? It has a loading
effect that is variable depending upon where on the driven element
it would be placed ... more effect at the ends where the E-field is
greater and almost no effect at the center.
Just some thoughts ...
Dave?? AB7E
On 3/26/2025 9:35 AM, Martin DK 3 UW
via groups.io wrote:
toggle quoted message
Show quoted text
I am building a 6 m 2 el Yagi dK7ZB design and it is matched
with a transformer made from 75 Ohm coax. 2 stubs of 1/4 Lambda
in parallel. I tohought I could ?put a 28 Ohm resistor replacing
the radiator ?and then have 50 Ohms on the Nano VNA at 50 Mhz
resonnance. ?But that is not, what I see. ?Resonance is 37.8 Mhz
?at 47 Ohms resitance . At 50 Mhz resistance would be 38 Ohms
and SWR 1,4. ?Prior to that I had mesured the coax with a
velocity factor of 1 and could calculate a Velocity factor of
0,63 for the cable which is an unknown TV cable. Then calculated
the lenth with that VF so I thought I should not be too far of.
? Any suggestions ?
?
?
Marin
DK3 UW
|
Re: matching 6 m 2 element Yagi
well I used the VF of 1 to calulate the VF of the Coax . The NVNA showed something like 2,4 m for the real lenth of 1.5m so that calulated a VF of 0.63 for the coax. Then I calculated 75/50,1x0,63 for the coax lenght. One piece with shortened end gives the naround 50 Mhz so that fits. For the Yagi according to DK7ZB it should be 2 coaxes in parallel to tranasform the 28 Ohms to 50 Ohms. Actually I am unable to mesaure that. I would have liked to check that before mounting it to the antenna.
?
?
Martin
DK3UW
|
On Wed, Mar 26, 2025 at 11:25 AM, Michael VE3WMB wrote:
Having 3/8-24 threading at the base means that this antenna can also be extended with Buddipole (or other antenna parts).
Asian and European components frequently have M10 threads, fortunately there are thread adapters available, like this one From Chelegance
The set consists of one male and one female of each thread size so the conversion works either way.? Nicely machined from (presumably) brass, I used mine to adapt a homebrew coil assembly from a European ham to my USA whip, clamp, etc.
73, Don N2vGU
?
|
Re: matching 6 m 2 element Yagi
You need to know what the real VF for the coax used.
That and there is no such thing as a coax with VF=1.
?
Having built that transformer I found with known 1/4 wavelength?
measured using VNA the transformation was very close to the
28 ohms.? However if the VF is incorrect it will be very wrong.
?
For the cable used a cable of VF=1 would be 58 inches(approximate)
but for real 75ohm RG59 VF was .68 was close to 40" and connectors
internal length counted as part of the actual electrical length.
?
Generally TV cable is foamed core with VF closer to .8(not exact
and varies)?and solid insultator cored cables closer to .66 but
until you measure it will be a genralization at best.
?
--
Allison
--------------------------
Please, private email goes to bit bucket
|
Re: matching 6 m 2 element Yagi
Hello Marin,
I assume your goal is to achieve a better match between the antenna and the feed line.
Perhaps you could use a single piece of 75¦¸ coax, cut to 1/4 Lambda, inserted between the antenna's feed point and your 50¦¸ feed line.?
If the dipole feed point is close to 72¦¸, then this arrangement could be expected to present approximate 60¦¸ to the 50¦¸ feed line.?
This should give you a 1.2:1 SWR.??
72 x 50 = 3600, ?? (3600)^0.5 =? 60, ? 60/50 = 1.20 SWR? Not perfect, but close.?
Good luck!? Tom K4AKC
----------------
toggle quoted message
Show quoted text
On 2025-03-26 11:35 am, Martin DK 3 UW via groups.io wrote:
I am building a 6 m 2 el Yagi dK7ZB design and it is matched with a transformer made from 75 Ohm coax. 2 stubs of 1/4 Lambda in parallel. I tohought I could ?put a 28 Ohm resistor replacing the radiator ?and then have 50 Ohms on the Nano VNA at 50 Mhz resonnance. ?But that is not, what I see. ?Resonance is 37.8 Mhz ?at 47 Ohms resitance . At 50 Mhz resistance would be 38 Ohms and SWR 1,4. ?Prior to that I had mesured the coax with a velocity factor of 1 and could calculate a Velocity factor of 0,63 for the cable which is an unknown TV cable. Then calculated the lenth with that VF so I thought I should not be too far of. ? Any suggestions ?
?
?
Marin
DK3 UW
|
Mike.
We are?in violent agreement here. I have the MFJ 1898, essentially the same thing.
I can't understand why so little has been written about?it.? Especially because it usually eliminates the need for a tuner with IC705 and FT817 operations.
At the risk of being thought daft, I also run it on the KX2 handheld with a little bracket.
72 Scott
Doug, I too am enjoying this thread. Do you have a reference for the HB vertical, how it is used/connected, or is it a QRPGuys design? I am always looking for antennas to play with, test and experiment with.?
I am cheap, ie a ham, so bought a used, well priced KX2 that came with an AX1. It has become my favorite POTA activation rig right now, 99% on CW. Set up less than 5 minutes. Most activations when in a bit of a hurry less than 30 minutes. Practical experience indicates that counterpoise placement is important, usually with the radio on the hood of my truck with the counterpoise draped across it. Antenna directly connected to the radio using a printed antenna support.?
When backpacking a lot, I was one of those guys that cut the handle off my toothbrush for efficiency. Weight isn¡¯t as much of an issue today, but bulk is. Doug, I have put together my version of a vertical that will connect directly to the radio. It works, but not much better than the AX1, if at all. Again, almost only CW. Bicycle or walking portable is common.?
72
john, NS6X?
|
Re: AX1 - Collapsible Whips
Chameleon also has a 25¡¯ extendable whip for $100. Also available at DX Engineering with free shipping due to price. Very well built. ? ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Lee KX4TT via groups.io
Sent: Tuesday, March 25, 2025 11:10 PM
To: [email protected]
Subject: Re: [qrparci] AX1 - Collapsible Whips? The Chameleon whips are built pretty well at the bottom. The early MFJ whips were quite fragile, but the later ones were much better. The Chameleons are still built better than the MFJ items..............
73 de Lee KX4TT On Tuesday, March 25, 2025 at 06:39:40 PM EDT, MIKE N6ZW via groups.io <n6zw@...> wrote: Those are the same that MFJ used to sell before they went closed their doors. I use one for several HB antennas and it works very well alone. You can even base load one easily.? 73,? Mike n6zw On 03/25/2025 3:28 PM PDT Dave AB7E via groups.io <ab7echo@...> wrote:
I forgot to include the link to the SS17 whip:
The pictures in the first review are mine (Alice is my wife's name).
Dave? AB7E
-------- Forwarded Message --------
Except that the AX1 isn't enough of a vertical to actually act like a short vertical.? If you model an AX1 and look at the current distribution you will see that most of it is in the counterpoise wire.? To be honest, the AX1 whip is mostly a convenient lossy tank circuit to act as a counterpoise for the counterpoise wire ... or in some case, the shield of the coax feedline.
I know how to use EZNEC.? I've used it continually since 1993 or so when it was still called ELNEC, and I'm actually a big fan of vertical antennas for portable operation.? My choice, though, is the Chameleon SS17 collapsible whip with elevated radials.? My version weighs about 3.5 pounds ... with steel stakes ... and I can set it up in less than ten minutes.
An an end fed wire doesn't have to be very far off the ground to avoid being a worm warmer.? Why do you think elevated radials work when they are only a foot or two off the ground??? I'm not actually a big fan of end fed wire antennas, but for portable use I don't think they can be beat for performance, size, weight, or cost.? I wish I had an AX1 to compare against various alternatives using WSPR, but I'm not willing to spend the money on one just to prove ... or disprove, if that should be the case ... my point.? Curiously, almost nobody who owns an AX1 has bothered to do a similarly rigorous A-vs-B comparison either.? Presumably, like you, they don't really care as long as "it works".
Dave?? AB7E
On 3/25/2025 2:44 PM, Dan N7CQR via groups.io wrote: I¡¯ve used this strategy on bare summits above 3-4000 feet with some success. Unfortunately at sea level or low elevation you¡¯re just warming the earthworms. Any type of short vertical with an elevated radial will provide a decent takeoff angle. You can model this in EZNEC. A good resource for using short verticals effectively are the writings of Jerry Severns for the ARRL Antenna handbook or the website for antenna ¡®guru¡¯ LB Cebik.?
On Mar 25, 2025, at 12:42, Dave AB7E via groups.io <AB7Echo@...> wrote:
You should try the EFRW sometime just laying on the ground, or maybe laying across a rock.? I'll say again ... most of the radiating from an AX1 comes from either the counterpoise or the shield of the coax (if not using a common mode choke), and for the majority of uses either of those are lying on or very near the top of the ground.? The surface of most "ground" isn't an RF ground, and if the soil is dry or fairly non-conductive the actual RF ground is probably several feet below the surface.? Not sure what the ground characteristic in the Orkneys is, though.
Dave?? AB7E
On 3/25/2025 12:18 PM, Dan N7CQR via groups.io wrote: I forgot to mention that I also carry a EFRW in my little bag,that of course is more efficient than almost short loaded vertical. Mine is Adam¡¯s K6ARK clever design that incorporates a 9:1 balun into the BNC connector. But you have to have either a tree or a pole to toss it into. If you¡¯ve been to the Orkneys you know that there¡¯s not many trees there¡?
On Mar 25, 2025, at 11:22, Dan N7CQR via groups.io <N7CQR@...> wrote:
It¡¯s a matter of trade offs that each operator is willing to make. No doubt that other larger antennas can be more efficient,but how much are you willing to pack around? Last summer I made a trip to the Orkney Islands,and you are definitely limited in how much baggage you can bring on a very small plane. . Wanting to get some radio time in,it¡¯s an easy decision to bring my small bag and still have room for clothing and other essentials. And I successfully got on the air with the AX1 at 5W. Worked 10 countries in one 45 minute session. For me that¡¯s a good trade off. ?Back home I use the best antenna I can reasonably carry. Lately I¡¯ve been using the Chelegance MC 750 vertical which is a full 1/4 wave on 20-10 Meters with the KH1 and having excellent results. It breaks down into a relatively small package-but still nothing I¡¯d ever fly or take a longer hike with. We have so many great options these days.?
|
matching 6 m 2 element Yagi
I am building a 6 m 2 el Yagi dK7ZB design and it is matched with a transformer made from 75 Ohm coax. 2 stubs of 1/4 Lambda in parallel. I tohought I could ?put a 28 Ohm resistor replacing the radiator ?and then have 50 Ohms on the Nano VNA at 50 Mhz resonnance. ?But that is not, what I see. ?Resonance is 37.8 Mhz ?at 47 Ohms resitance . At 50 Mhz resistance would be 38 Ohms and SWR 1,4. ?Prior to that I had mesured the coax with a velocity factor of 1 and could calculate a Velocity factor of 0,63 for the cable which is an unknown TV cable. Then calculated the lenth with that VF so I thought I should not be too far of. ? Any suggestions ?
?
?
Marin
DK3 UW
|
Doug, I too am enjoying this thread. Do you have a reference for the HB vertical, how it is used/connected, or is it a QRPGuys design? I am always looking for antennas to play with, test and experiment with.?
I am cheap, ie a ham, so bought a used, well priced KX2 that came with an AX1. It has become my favorite POTA activation rig right now, 99% on CW. Set up less than 5 minutes. Most activations when in a bit of a hurry less than 30 minutes. Practical experience indicates that counterpoise placement is important, usually with the radio on the hood of my truck with the counterpoise draped across it. Antenna directly connected to the radio using a printed antenna support.?
When backpacking a lot, I was one of those guys that cut the handle off my toothbrush for efficiency. Weight isn¡¯t as much of an issue today, but bulk is. Doug, I have put together my version of a vertical that will connect directly to the radio. It works, but not much better than the AX1, if at all. Again, almost only CW. Bicycle or walking portable is common.?
72
john, NS6X?
|
On Tue, Mar 25, 2025 at 10:37 AM, Scott KA9P wrote:
I'm not anti-AX1 or Elecraft, God knows Wayne has enough of my money.? But it would be fun to see a Super AX-1A that is more efficient, easily packed and exploits the superb tuner in the KX2 to its maximum benefit., I might have to part with more money then. :)
My packable go-anywhere antenna is the Gabil GRA-7350TC (available on Amazon).? It is perhaps best-described as a small manual-screwdriver-type antenna with a removeable telescopic whip. When assembled it is about 7 feet long (i.e. Hamstick sized) but it packs into a sleeve (I use a Soprano recorder case) only 13 inches long which fits nicely either inside my daypack or in the mesh water bottle pocket on the outside of the pack.? The base has 3/8-24 threads so it can be used with any 3/8" mount but it is best paired with the absolutely tiny but highly functional companion Gabil GRA-ULT01 Tripod.? This is the smallest packing functional antenna tripod I have even seen.? When packed up it is about 4 inches in diameter and about 6 inches long. The antenna covers 40m through 6m and the the tuning granularity on the telescopic coil is fine enough that I always just extend the whip fully for HF and tune via the the coil. The newest version has the graduated tuning scale laser etched for longevity.?
I use this primarily as a vacation antenna, along with my KH1 or KX2 for those times when I want a little better performance than the AX1 delivers, so I guess it sort of fits the function of a "super-AX1A".?
?
FWIW, the build quality of the Gabil components is excellent. I also have the optional Gabil shock-corded? whip which is physically a bit longer than the telescopic whip when when deployed, but also doesn't pack quite as small.? Its certainly more rugged than the telescopic whip.??I have a few other friends who also have the Gabil and agree that for the size it is versatile and performs quite well as a portable antenna or on a mobile antenna mount for stationary mobile operating.?
?
Cheers
?
Michael VE3WMB?
?
P.S. Having 3/8-24 threading at the base means that this antenna can also be extended with Buddipole (or other antenna parts). I normally operate my Gabil with a short arm (11 inches) designed for the Buddistick to move the coil up from the base of the antenna to improve efficiency slightly.? The short arm fits into the recorder case along with the coil and whip.?
?
?
?
|
On
3/24/25 I had a CW practice / rag chew session on 20 meters.
I worked three stations:
| Date
/ Time |
Call |
Bnd |
Frequency |
Mode |
Power |
Rec |
Snt |
SPC# |
Name |
Comments |
Off |
| 3/24/2025
19:25 |
AE4IX |
20 |
14.054 |
CW |
100 |
599 |
559 |
VA |
Rick |
K3
at 100 watts 100 ft sloper doublet |
19:43 |
| 3/24/2025
19:11 |
K4WNY |
20 |
14.054 |
CW |
100 |
589 |
599 |
TN |
Ron |
K3
at 100 watts 100 ft sloper doublet |
19:24 |
| 3/24/2025
19:08 |
K6GRD |
20 |
14.043 |
CW |
100 |
569 |
449 |
UT |
Rick |
K3
at 100 watts 100 ft sloper doublet |
|
Conditions were OK with
QSB on all stations but better than it was on Sunday. SSN =
110, SFI = 168, A = 10, K = 3.
My next CW practice session will be?March 28
at 09:00 EDT / 13:00 UTC on 20 meters.?Anyone and
everyone is welcome. This practice is intended for
operators who are new to CW or they need some practice. IT
DOES NOT MATTER HOW POOR YOUR CW IS. Mistakes are OK. Poor
fists are OK. Slow speed is OK. Really slow speed is OK.
This practice is meant for you to improve your CW. I will
do my best to adjust to your skill level. Operate at any
power level. If several stations show up, I will operate
as a round-table control station. I will do it as a
round-table so everyone gets a chance to transmit. Please
listen to my directions.
Details:
Date -
March 28 2025
Time - 09:00 EDT ?13:00 UTC
Band - 20 Meters
How to find me - I will find a clear frequency and call
CQ. Go to the Reverse Beacon Network and search for my
call sign AB8DF.
That will tell you
what frequency I am on. Tune your station to that
frequency and if you hear me give me a call. If there is a
QSO in progress, please wait for a break in the action.
Then send your callsign. If I hear you, I will invite you
to join the QSO and start a round-table QSO.
Reply to this email if you have questions.
IT DOES NOT MATTER HOW POOR CW IS
Ed
AB8DF_._,_._,_
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Re: AX1 - Collapsible Whips
My preferred is the AT271 bungee cord whips they are 9.3FT (least mine are).
The fold down to 16" and assemble very fast and strong.??They are avaiable
from several sources, not all identical.? Sometimes called PRC25 or PRC77
manpack antenna. If I need taller I have several 18" aluminum rods with
the correct thread and couplers.
?
Generally not a fan of stainless whips, the stainless is strong but has
high resistance and losses at RF.? Depite that, they are handy and I
have a few good ones from Buddypole.
?
--
Allison
--------------------------
Please, private email goes to bit bucket
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Re: Black Widow antenna instructions
Dave:
I emailed you a file I found in my archives.
72, Craig WB3GCK
On Wed, Mar 26, 2025 at 6:46?AM David Wilcox K8WPE via <Djwilcox01= [email protected]> wrote: Does anyone have the full instructions to the Black Widow vertical antenna that was designed and sold by Ed Breneiser WA3WSJ?? So far the Wayback Machine only has snippets of it.? Eds stuff has been pulled down sadly.? I am trying to relive yesteryear with a build and use like I did back in the old mobile home cottage we had back then.? Just for fun.?
Dave K8WPE
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Black Widow antenna instructions
Does anyone have the full instructions to the Black Widow vertical antenna that was designed and sold by Ed Breneiser WA3WSJ? So far the Wayback Machine only has snippets of it. Eds stuff has been pulled down sadly. I am trying to relive yesteryear with a build and use like I did back in the old mobile home cottage we had back then. Just for fun.
Dave K8WPE
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Re: AX1 - Collapsible Whips
The Chameleon whips are built pretty well at the bottom. The early MFJ whips were quite fragile, but the later ones were much better. The Chameleons are still built better than the MFJ items..............
73 de Lee KX4TT
On Tuesday, March 25, 2025 at 06:39:40 PM EDT, MIKE N6ZW via groups.io <n6zw@...> wrote:
Those are the same that MFJ used to sell before they went closed their doors. I use one for several HB antennas and it works very well alone. You can even base load one easily.? 73,? Mike n6zw
On 03/25/2025 3:28 PM PDT Dave AB7E via groups.io <ab7echo@...> wrote: ? ? I forgot to include the link to the SS17 whip:
The pictures in the first review are mine (Alice is my wife's name).
Dave? AB7E
-------- Forwarded Message -------- Except that the AX1 isn't enough of a vertical to actually act like a short vertical.? If you model an AX1 and look at the current distribution you will see that most of it is in the counterpoise wire.? To be honest, the AX1 whip is mostly a convenient lossy tank circuit to act as a counterpoise for the counterpoise wire ... or in some case, the shield of the coax feedline.
I know how to use EZNEC.? I've used it continually since 1993 or so when it was still called ELNEC, and I'm actually a big fan of vertical antennas for portable operation.? My choice, though, is the Chameleon SS17 collapsible whip with elevated radials.? My version weighs about 3.5 pounds ... with steel stakes ... and I can set it up in less than ten minutes.
An an end fed wire doesn't have to be very far off the ground to avoid being a worm warmer.? Why do you think elevated radials work when they are only a foot or two off the ground??? I'm not actually a big fan of end fed wire antennas, but for portable use I don't think they can be beat for performance, size, weight, or cost.? I wish I had an AX1 to compare against various alternatives using WSPR, but I'm not willing to spend the money on one just to prove ... or disprove, if that should be the case ... my point.? Curiously, almost nobody who owns an AX1 has bothered to do a similarly rigorous A-vs-B comparison either.? Presumably, like you, they don't really care as long as "it works".
Dave?? AB7E
On 3/25/2025 2:44 PM, Dan N7CQR via groups.io wrote: I¡¯ve used this strategy on bare summits above 3-4000 feet with some success. Unfortunately at sea level or low elevation you¡¯re just warming the earthworms. Any type of short vertical with an elevated radial will provide a decent takeoff angle. You can model this in EZNEC. A good resource for using short verticals effectively are the writings of Jerry Severns for the ARRL Antenna handbook or the website for antenna ¡®guru¡¯ LB Cebik.?
Dan Presley 503-701-3871 danpresley@me. com? ? On Mar 25, 2025, at 12:42, Dave AB7E via groups.io <AB7Echo@...> wrote:
You should try the EFRW sometime just laying on the ground, or maybe laying across a rock.? I'll say again ... most of the radiating from an AX1 comes from either the counterpoise or the shield of the coax (if not using a common mode choke), and for the majority of uses either of those are lying on or very near the top of the ground.? The surface of most "ground" isn't an RF ground, and if the soil is dry or fairly non-conductive the actual RF ground is probably several feet below the surface.? Not sure what the ground characteristic in the Orkneys is, though. Dave?? AB7E On 3/25/2025 12:18 PM, Dan N7CQR via groups.io wrote: I forgot to mention that I also carry a EFRW in my little bag,that of course is more efficient than almost short loaded vertical. Mine is Adam¡¯s K6ARK clever design that incorporates a 9:1 balun into the BNC connector. But you have to have either a tree or a pole to toss it into. If you¡¯ve been to the Orkneys you know that there¡¯s not many trees there¡?
Dan Presley 503-701-3871 danpresley@me. com? ? On Mar 25, 2025, at 11:22, Dan N7CQR via groups.io <N7CQR@...> wrote:
It¡¯s a matter of trade offs that each operator is willing to make. No doubt that other larger antennas can be more efficient,but how much are you willing to pack around? Last summer I made a trip to the Orkney Islands,and you are definitely limited in how much baggage you can bring on a very small plane. . Wanting to get some radio time in,it¡¯s an easy decision to bring my small bag and still have room for clothing and other essentials. And I successfully got on the air with the AX1 at 5W. Worked 10 countries in one 45 minute session. For me that¡¯s a good trade off. ?Back home I use the best antenna I can reasonably carry. Lately I¡¯ve been using the Chelegance MC 750 vertical which is a full 1/4 wave on 20-10 Meters with the KH1 and having excellent results. It breaks down into a relatively small package-but still nothing I¡¯d ever fly or take a longer hike with. We have so many great options these days.? Dan Presley 503-701-3871 danpresley@me. com? ?
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Jay W6CJ
Brian KB9BVN
Don N2VGU
Craig WB3GCK
David Wilcox K8WPE
Lee KX4TT