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On Tue, Feb 27, 2024 at 09:04 AM, Jim Lux wrote:

Here’s an idea.. coax (with an RF choke at 1/4 wavelength from end), then
continue the center conductor another 1/4 wavelength. That gives you a

center

fed dipole (so Z is low) AND the feedline coming off the end. Basically a
sleeve dipole turned sideways.

Jim, I've been waiting for someone to comment on this clever idea. Before
this thread gets locked, I wanted to tell you that you rediscovered the
Flower Pot antenna:



Click on FLOWER POTS

A VNA could be used to fine-tune the coil self-resonance.

Brian

On Tue, Feb 27, 2024 at 09:04 AM, Jim Lux wrote:

Here’s an idea.. coax (with an RF choke at 1/4 wavelength from end), then
continue the center conductor another 1/4 wavelength. That gives you a

center

fed dipole (so Z is low) AND the feedline coming off the end. Basically a
sleeve dipole turned sideways.

Jim, I've been waiting for someone to comment on this clever idea. Before
this thread gets locked, I wanted to tell you that you rediscovered the
Flower Pot antenna:



Click on FLOWER POTS

A VNA could be used to fine-tune the coil self-resonance.

Brian

On 03/02/2024 10:00 AM EST Brian Beezley < k6sti@... > wrote:


I hate it when I fumble a key and the message gets sent before I'm done.
It should say click on FLOWER POTS for the origin story.

I think I'd add another coil a quarter wavelength down the feedline to
suppress any residual current.

SOTA people (summits on the air) use these antennas when operating
portable on summits, most often on 2m but lately on 10m as well. They love
them.

Brian=-=-=-=-=-=-=-

The android web app may have been a workaround - its too bad there's been no work on this in like 4 years, I wonder if it could be remoted to.

Andy

On Mar 1, 2024, at 20:16, W0LEV <davearea51a@...> wrote:

?Dave, let's kill it. I, as well, am growing tired of the end fed wires.

DE

On Sat, Mar 2, 2024 at 12:31?AM Dave Daniel <kc0wjn@...> wrote:

This discussion is getting a bit too off-topic for this list. Going
forward, let's either bring it back on-topic or kill it.

Thanks.

DaveD

On Mar 1, 2024, at 19:15, W0LEV <davearea51a@...> wrote:

?Having once worked for NASA, I would SERIOUSLY doubt NASA ever....and I

do

mean ever...... used ANYthing from MFJ. Far too many hams who work for
NASA know about the shortcomings of MJF products. I have never.....N E

V E

R..... bought and used an MJF product that didn't need some internal work
to operate properly.

Other moderators: Please forgive me for relating something bad about a
supplier, but I've had personal experience as have many other amateur

radio

operators.

Dave - W?LEV

On Fri, Mar 1, 2024 at 5:17?AM Jim Lux <jimlux@...> wrote:

No idea, but if NASA buys something, the mfr sometimes says “as used by
狈础厂础”.
For all we know, someone bought one for the ham club at one of the

centers.

There’s a somewhat famous story about a NASA funded a study to test the
lack of efficacy of something (lightning eliminators?) and all the
manufacturers of the bogus equipment started advertising “as used by

狈础厂础”.

On Feb 29, 2024, at 4:52?PM, N2MS <mstangelo@...> wrote:

?How about the term counterpoise as a return? If the return is a wire

or

wires we can refer to it as radial(s)?

I recall HF communications was tested on a Project Gemini Flight. I

don't remember the details but they used R390A receivers at the ground
stations.

I have a report about with the details. If found I will post it.

Since were discussing space and analyzers MFJ mentioned in one of their

recent ads that their Antenna Analyzer was used by NASA. Does anyone

have

any information about this?

Mike N2MS

On 02/29/2024 6:52 PM EST W0LEV <davearea51a@...> wrote:


Jim Lux, I just have a lot of trouble with RF energy and the term
"ground". It's maligned in the amateur circles. There is no need for
"ground" with RF fields, just a return.

Please comment.

Dave - W?LEV

On Thu, Feb 29, 2024 at 7:51?PM Jim Lux <jimlux@...>

wrote:

ISS isn't using HF long wires, either. Most of its antennas are

things

like patches (which are a sort of end fed dipole) or horns (which

have

tiny

monopoles in the feed point) possibly illuminating a dish.

There *are* spacecraft that use monopoles for HF and lower (they're
generically called "fields and waves experiments") - for them, the
feedpoint is the junction of the wire/boom with the spacecraft body,

so

it's a fairly asymmetrical antenna. Cassini has several booms at
different angles.

And often, because a full size antenna for 1 MHz is quite large (300

meter

wavelength), the antennas are more "voltage probes", with a high Z
amplifier measuring the voltage at the base of the antenna.

On HF sounders (running around 9 MHz) such as MARSIS or REASON (the

latter

is on Europa Clipper) it's an actual dipole, although not necessarily
resonant.

On *my* space vehicles (SunRISE mission), there's two crossed dipoles

with

2.5 meter booms, feeding a balanced FET input preamplifier.



-----Original Message-----
From: <[email protected]>
Sent: Feb 29, 2024 10:08 AM
To: <[email protected]>
Subject: Re: [nanovna-users] where is the end fed natural resonance

The word counterpoise has no applications in amateur radio, but most

times,

it is misused and misapplied. I just checked all my graduate and one
undergrad antenna references. Nowhere is the term "counterpoise" to

be

found. Then I checked Wikipedia. The opening verbiage gives the
"standard" understanding, quoted below:

In electronics and radio communication, a *counterpoise* is a network

of

suspended horizontal wires or cables (or a metal screen), used as a
substitute for an earth (ground) connection in a radio antenna

system.

It

is used with radio transmitters or receivers when a normal earth

ground

cannot be used because of high soil resistance or when an antenna
is&hellip;
Read More

Further, the first reference listed in the Wikipedia article is

Cebik.

For decades I have been using the term "image plane" in reference to

the

more common (and misused) term "ground plane". I believe in using the

term

"counterpoise", we truly are referring to the "image plane". So,

Cebik

is

correct in discouraging the (mis)use of the term "counterpoise".

Indeed,

all my references include treatment of "image theory". Again, none of
these treat or address "counterpoise".

I also point out that the ISS has no mechanism of connecting to

"ground"

for a "ground plane". But,.......drum roll........its occupants have
absolutely no trouble bidirectionally communicating with earth via a
number of RF links. Absolutely no "ground" involved.

Dave - W&Oslash;LEV

--

*Dave - W?LEV*


--
Dave - W?LEV

--

*Dave - W?LEV*


--
Dave - W?LEV

This discussion is getting a bit too off-topic for this list. Going
forward, let's either bring it back on-topic or kill it.

Thanks.

DaveD

On Mar 1, 2024, at 19:15, W0LEV <davearea51a@...> wrote:

?Having once worked for NASA, I would SERIOUSLY doubt NASA ever....and I

do

mean ever...... used ANYthing from MFJ. Far too many hams who work for
NASA know about the shortcomings of MJF products. I have never.....N E

V E

R..... bought and used an MJF product that didn't need some internal work
to operate properly.

Other moderators: Please forgive me for relating something bad about a
supplier, but I've had personal experience as have many other amateur

radio

operators.

Dave - W?LEV

On Fri, Mar 1, 2024 at 5:17?AM Jim Lux <jimlux@...> wrote:

No idea, but if NASA buys something, the mfr sometimes says “as used by
狈础厂础”.
For all we know, someone bought one for the ham club at one of the

centers.

There’s a somewhat famous story about a NASA funded a study to test the
lack of efficacy of something (lightning eliminators?) and all the
manufacturers of the bogus equipment started advertising “as used by

狈础厂础”.

On Feb 29, 2024, at 4:52?PM, N2MS <mstangelo@...> wrote:

?How about the term counterpoise as a return? If the return is a wire

or

wires we can refer to it as radial(s)?

I recall HF communications was tested on a Project Gemini Flight. I

don't remember the details but they used R390A receivers at the ground
stations.

I have a report about with the details. If found I will post it.

Since were discussing space and analyzers MFJ mentioned in one of their

recent ads that their Antenna Analyzer was used by NASA. Does anyone

have

any information about this?

Mike N2MS

On 02/29/2024 6:52 PM EST W0LEV <davearea51a@...> wrote:


Jim Lux, I just have a lot of trouble with RF energy and the term
"ground". It's maligned in the amateur circles. There is no need for
"ground" with RF fields, just a return.

Please comment.

Dave - W?LEV

On Thu, Feb 29, 2024 at 7:51?PM Jim Lux <jimlux@...>

wrote:

ISS isn't using HF long wires, either. Most of its antennas are

things

like patches (which are a sort of end fed dipole) or horns (which

have

tiny

monopoles in the feed point) possibly illuminating a dish.

There *are* spacecraft that use monopoles for HF and lower (they're
generically called "fields and waves experiments") - for them, the
feedpoint is the junction of the wire/boom with the spacecraft body,

so

it's a fairly asymmetrical antenna. Cassini has several booms at
different angles.

And often, because a full size antenna for 1 MHz is quite large (300

meter

wavelength), the antennas are more "voltage probes", with a high Z
amplifier measuring the voltage at the base of the antenna.

On HF sounders (running around 9 MHz) such as MARSIS or REASON (the

latter

is on Europa Clipper) it's an actual dipole, although not necessarily
resonant.

On *my* space vehicles (SunRISE mission), there's two crossed dipoles

with

2.5 meter booms, feeding a balanced FET input preamplifier.



-----Original Message-----
From: <[email protected]>
Sent: Feb 29, 2024 10:08 AM
To: <[email protected]>
Subject: Re: [nanovna-users] where is the end fed natural resonance

The word counterpoise has no applications in amateur radio, but most

times,

it is misused and misapplied. I just checked all my graduate and one
undergrad antenna references. Nowhere is the term "counterpoise" to

be

found. Then I checked Wikipedia. The opening verbiage gives the
"standard" understanding, quoted below:

In electronics and radio communication, a *counterpoise* is a network

of

suspended horizontal wires or cables (or a metal screen), used as a
substitute for an earth (ground) connection in a radio antenna

system.

It

is used with radio transmitters or receivers when a normal earth

ground

cannot be used because of high soil resistance or when an antenna
is&hellip;
Read More

Further, the first reference listed in the Wikipedia article is

Cebik.

For decades I have been using the term "image plane" in reference to

the

more common (and misused) term "ground plane". I believe in using the

term

"counterpoise", we truly are referring to the "image plane". So,

Cebik

is

correct in discouraging the (mis)use of the term "counterpoise".

Indeed,

all my references include treatment of "image theory". Again, none of
these treat or address "counterpoise".

I also point out that the ISS has no mechanism of connecting to

"ground"

for a "ground plane". But,.......drum roll........its occupants have
absolutely no trouble bidirectionally communicating with earth via a
number of RF links. Absolutely no "ground" involved.

Dave - W&Oslash;LEV

--

*Dave - W?LEV*


--
Dave - W?LEV

On Mar 1, 2024, at 19:15, W0LEV <davearea51a@...> wrote:

?Having once worked for NASA, I would SERIOUSLY doubt NASA ever....and I do
mean ever...... used ANYthing from MFJ. Far too many hams who work for
NASA know about the shortcomings of MJF products. I have never.....N E V E
R..... bought and used an MJF product that didn't need some internal work
to operate properly.

Other moderators: Please forgive me for relating something bad about a
supplier, but I've had personal experience as have many other amateur radio
operators.

Dave - W?LEV

On Fri, Mar 1, 2024 at 5:17?AM Jim Lux <jimlux@...> wrote:

No idea, but if NASA buys something, the mfr sometimes says “as used by
狈础厂础”.
For all we know, someone bought one for the ham club at one of the centers.

There’s a somewhat famous story about a NASA funded a study to test the
lack of efficacy of something (lightning eliminators?) and all the
manufacturers of the bogus equipment started advertising “as used by 狈础厂础”.

On Feb 29, 2024, at 4:52?PM, N2MS <mstangelo@...> wrote:

?How about the term counterpoise as a return? If the return is a wire or

wires we can refer to it as radial(s)?

I recall HF communications was tested on a Project Gemini Flight. I

don't remember the details but they used R390A receivers at the ground
stations.

I have a report about with the details. If found I will post it.

Since were discussing space and analyzers MFJ mentioned in one of their

recent ads that their Antenna Analyzer was used by NASA. Does anyone have
any information about this?

Mike N2MS

On 02/29/2024 6:52 PM EST W0LEV <davearea51a@...> wrote:


Jim Lux, I just have a lot of trouble with RF energy and the term
"ground". It's maligned in the amateur circles. There is no need for
"ground" with RF fields, just a return.

Please comment.

Dave - W?LEV

On Thu, Feb 29, 2024 at 7:51?PM Jim Lux <jimlux@...> wrote:

ISS isn't using HF long wires, either. Most of its antennas are things
like patches (which are a sort of end fed dipole) or horns (which have

tiny

monopoles in the feed point) possibly illuminating a dish.

There *are* spacecraft that use monopoles for HF and lower (they're
generically called "fields and waves experiments") - for them, the
feedpoint is the junction of the wire/boom with the spacecraft body, so
it's a fairly asymmetrical antenna. Cassini has several booms at
different angles.

And often, because a full size antenna for 1 MHz is quite large (300

meter

wavelength), the antennas are more "voltage probes", with a high Z
amplifier measuring the voltage at the base of the antenna.

On HF sounders (running around 9 MHz) such as MARSIS or REASON (the

latter

is on Europa Clipper) it's an actual dipole, although not necessarily
resonant.

On *my* space vehicles (SunRISE mission), there's two crossed dipoles

with

2.5 meter booms, feeding a balanced FET input preamplifier.



-----Original Message-----
From: <[email protected]>
Sent: Feb 29, 2024 10:08 AM
To: <[email protected]>
Subject: Re: [nanovna-users] where is the end fed natural resonance

The word counterpoise has no applications in amateur radio, but most

times,

it is misused and misapplied. I just checked all my graduate and one
undergrad antenna references. Nowhere is the term "counterpoise" to be
found. Then I checked Wikipedia. The opening verbiage gives the
"standard" understanding, quoted below:

In electronics and radio communication, a *counterpoise* is a network

of

suspended horizontal wires or cables (or a metal screen), used as a
substitute for an earth (ground) connection in a radio antenna system.

It

is used with radio transmitters or receivers when a normal earth ground
cannot be used because of high soil resistance or when an antenna
is&hellip;
Read More

Further, the first reference listed in the Wikipedia article is Cebik.

For decades I have been using the term "image plane" in reference to

the

more common (and misused) term "ground plane". I believe in using the

term

"counterpoise", we truly are referring to the "image plane". So, Cebik

is

correct in discouraging the (mis)use of the term "counterpoise".

Indeed,

all my references include treatment of "image theory". Again, none of
these treat or address "counterpoise".

I also point out that the ISS has no mechanism of connecting to

"ground"

for a "ground plane". But,.......drum roll........its occupants have
absolutely no trouble bidirectionally communicating with earth via a
number of RF links. Absolutely no "ground" involved.

Dave - W&Oslash;LEV

--

*Dave - W?LEV*


--
Dave - W?LEV

No idea, but if NASA buys something, the mfr sometimes says “as used by
狈础厂础”.
For all we know, someone bought one for the ham club at one of the centers.

There’s a somewhat famous story about a NASA funded a study to test the
lack of efficacy of something (lightning eliminators?) and all the
manufacturers of the bogus equipment started advertising “as used by 狈础厂础”.

On Feb 29, 2024, at 4:52?PM, N2MS <mstangelo@...> wrote:

?How about the term counterpoise as a return? If the return is a wire or

wires we can refer to it as radial(s)?

I recall HF communications was tested on a Project Gemini Flight. I

don't remember the details but they used R390A receivers at the ground
stations.

I have a report about with the details. If found I will post it.

Since were discussing space and analyzers MFJ mentioned in one of their

recent ads that their Antenna Analyzer was used by NASA. Does anyone have
any information about this?

Mike N2MS

On 02/29/2024 6:52 PM EST W0LEV <davearea51a@...> wrote:


Jim Lux, I just have a lot of trouble with RF energy and the term
"ground". It's maligned in the amateur circles. There is no need for
"ground" with RF fields, just a return.

Please comment.

Dave - W?LEV

On Thu, Feb 29, 2024 at 7:51?PM Jim Lux <jimlux@...> wrote:

ISS isn't using HF long wires, either. Most of its antennas are things
like patches (which are a sort of end fed dipole) or horns (which have

tiny

monopoles in the feed point) possibly illuminating a dish.

There *are* spacecraft that use monopoles for HF and lower (they're
generically called "fields and waves experiments") - for them, the
feedpoint is the junction of the wire/boom with the spacecraft body, so
it's a fairly asymmetrical antenna. Cassini has several booms at
different angles.

And often, because a full size antenna for 1 MHz is quite large (300

meter

wavelength), the antennas are more "voltage probes", with a high Z
amplifier measuring the voltage at the base of the antenna.

On HF sounders (running around 9 MHz) such as MARSIS or REASON (the

latter

is on Europa Clipper) it's an actual dipole, although not necessarily
resonant.

On *my* space vehicles (SunRISE mission), there's two crossed dipoles

with

2.5 meter booms, feeding a balanced FET input preamplifier.



-----Original Message-----
From: <[email protected]>
Sent: Feb 29, 2024 10:08 AM
To: <[email protected]>
Subject: Re: [nanovna-users] where is the end fed natural resonance

The word counterpoise has no applications in amateur radio, but most

times,

it is misused and misapplied. I just checked all my graduate and one
undergrad antenna references. Nowhere is the term "counterpoise" to be
found. Then I checked Wikipedia. The opening verbiage gives the
"standard" understanding, quoted below:

In electronics and radio communication, a *counterpoise* is a network

of

suspended horizontal wires or cables (or a metal screen), used as a
substitute for an earth (ground) connection in a radio antenna system.

It

is used with radio transmitters or receivers when a normal earth ground
cannot be used because of high soil resistance or when an antenna
is&hellip;
Read More

Further, the first reference listed in the Wikipedia article is Cebik.

For decades I have been using the term "image plane" in reference to

the

more common (and misused) term "ground plane". I believe in using the

term

"counterpoise", we truly are referring to the "image plane". So, Cebik

is

correct in discouraging the (mis)use of the term "counterpoise".

Indeed,

all my references include treatment of "image theory". Again, none of
these treat or address "counterpoise".

I also point out that the ISS has no mechanism of connecting to

"ground"

for a "ground plane". But,.......drum roll........its occupants have
absolutely no trouble bidirectionally communicating with earth via a
number of RF links. Absolutely no "ground" involved.

Dave - W&Oslash;LEV

? Low Power Microwave work??????
Low Frequency as in the IF Connections?
PL259-SO238? Looks pretty bad at 1 GHz.? Worse higher than that.


? ? On Friday, March 1, 2024 at 04:52:24 PM CST, W0LEV <
davearea51a@...> wrote:

? No, SMA connectors are not PL-259 by any stretch.? But they are pretty
much
the standard for low-power microwave work.

Dave - W?LEV

On Fri, Mar 1, 2024 at 6:43?PM Schrille via groups.io <schnappie=
[email protected]> wrote:

same here.
This kit is absolutely scrap.after a couple of test,the mini connectors
died
The tread of one of these sma connectors is also bad
After a few tries, I threw the whole board? in the trash can.

--

*Dave - W?LEV*


--
Dave - W?LEV

Low Power Microwave work??????
Low Frequency as in the IF Connections?
PL259-SO238 Looks pretty bad at 1 GHz. Worse higher than that.


On Friday, March 1, 2024 at 04:52:24 PM CST, W0LEV <
davearea51a@...> wrote:

No, SMA connectors are not PL-259 by any stretch. But they are pretty
much
the standard for low-power microwave work.

Dave - W?LEV

On Fri, Mar 1, 2024 at 6:43?PM Schrille via groups.io <schnappie=
[email protected]> wrote:

same here.
This kit is absolutely scrap.after a couple of test,the mini connectors
died
The tread of one of these sma connectors is also bad
After a few tries, I threw the whole board in the trash can.

--

*Dave - W?LEV*


--
Dave - W?LEV

same here.
This kit is absolutely scrap.after a couple of test,the mini connectors
died
The tread of one of these sma connectors is also bad
After a few tries, I threw the whole board? in the trash can.

On 03/01/2024 5:23 PM EST W0LEV <davearea51a@...> wrote:


QUOTE: What about the vertical “no radials needed” ads?

I have worked with several local hams who have "believed" the "no radials
needed" claims. Don't go there. that's marketingeeze. Mounted on the
soil surface, a.k.a., ground, OK. Why? Earth or soil is lossy and loss
makes any high SWR far more friendly to tame. However, when mounted in an
elevated position like on the roof, they become extremely cantankerous!!
Do't believe the claims of "no radials needed".

Dave - W?LEV

On Fri, Mar 1, 2024 at 4:31?PM Ray W8LYJ via groups.io <rcbenedict1545=
[email protected]> wrote:

Thanks the ARRL standards are helpful. I wonder if the ARRL actually
enforces the standards. What about the vertical “no radials needed” ads?
And the vertical antenna that uses four 4 ft ground rods.
I asked about several technical articles and was told ARRL does not verify
the engineering in articles
Ray
W8LYJ