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Re: Antenna question

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George Thornton

Re: Antenna question

This might be a stupid question, but here goes.

I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna. If I put it up it is going to have to be pretty close to the Yagi.

I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?

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Barry K3NDM

Re: Antenna question

George,
That is a very good question. However, it is hard to quess. But,
one thing going in your favor is that one antenna is horizontal and the
other is vertical. This will minimize the amount of coupling between the
two. If you can get some horizontal separation between the two, it just
might be physically safe. If you get really good decoupling, it could be
on the order of 30 db. that means that a 100 Watts will look like 100 mw
to your receiver.

I actually do a variant of what you are asking here. I have a
Carolina Windom and an 18' base tuned vertical. I know there must be
some interaction, but so far nothing has smoked. I know better than to
try this without really looking at it, but I didn't think and did it
anyway. My antennas are about 15-20 apart horizontally and 15 feet
vertically. Maybe I had better have a look at it myself. But, my guess
is you'll be OK as long as you don't need to receive at the same time
you are transmitting. You will overdrive your receiver and not hear
anything during transmissions, but the 100 mw or less into the receiver
should be physically safe. That part of the answer should be answered by
Elecraft as to the maximum energy the receiver can tolerate.

73,
Barry
K3NDM

On 2/11/2014 6:36 PM, George Thornton wrote:

> This might be a stupid question, but here goes.
>
> I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna. If I put it up it is going to have to be pretty close to the Yagi.
>
> I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?
>
>
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> Elecraft mailing list
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>
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>

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W1KSZ

Re: Antenna question

In reply to this post by George Thornton

I have a Pennant receiving antenna about 100' from my 160 Meter Antenna.
I put a scope on the Pennant coax and keyed the rig. At about 1 KW out, I
saw about 6 volts pk-pk.

I bought a Receiver protection device.

73, Dick, W1KSZ

On 2/11/2014 4:36 PM, George Thornton wrote:

Bill Turner

Re: Antenna question

In reply to this post by George Thornton

ORIGINAL MESSAGE: (may be snipped)

On 2/11/2014 3:36 PM, George Thornton wrote:
> I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?

REPLY:

The field around an antenna is very strong compared to the input of a
receiver which is expecting a fraction of a microwatt. Not something to
be messed with.

If you must do this I would recommend installing a relay to short out
the non-transmitting antenna, and you should sequence it so it closes a
few milliseconds before beginning TX and opens a few milliseconds after
ceasing TX. Even better than simple shorting, use an SPDT relay so that
when the relay activated, the antenna is disconnected and the receiver
input is shorted to ground, separate from the antenna. This provides
even more isolation between the two.

73, Bill W6WRT

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George Pontiakos

Re: Antenna question

I would do it at all! Especially at power

Sent from my iPhone

> On Feb 11, 2014, at 7:16 PM, Bill Turner <[hidden email]> wrote:
>
> ORIGINAL MESSAGE: (may be snipped)
>
>> On 2/11/2014 3:36 PM, George Thornton wrote:
>> I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?
>
> REPLY:
>
> The field around an antenna is very strong compared to the input of a receiver which is expecting a fraction of a microwatt. Not something to be messed with.
>
> If you must do this I would recommend installing a relay to short out the non-transmitting antenna, and you should sequence it so it closes a few milliseconds before beginning TX and opens a few milliseconds after ceasing TX. Even better than simple shorting, use an SPDT relay so that when the relay activated, the antenna is disconnected and the receiver input is shorted to ground, separate from the antenna. This provides even more isolation between the two.
>
>
>
> 73, Bill W6WRT
>
> ______________________________________________________________
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George Pontiakos

Re: Antenna question

NOT

Sent from my iPhone

> On Feb 11, 2014, at 7:20 PM, Monovasia <[hidden email]> wrote:
>
> I would do it at all! Especially at power
>
> Sent from my iPhone
>
>> On Feb 11, 2014, at 7:16 PM, Bill Turner <[hidden email]> wrote:
>>
>> ORIGINAL MESSAGE: (may be snipped)
>>
>>> On 2/11/2014 3:36 PM, George Thornton wrote:
>>> I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?
>>
>> REPLY:
>>
>> The field around an antenna is very strong compared to the input of a receiver which is expecting a fraction of a microwatt. Not something to be messed with.
>>
>> If you must do this I would recommend installing a relay to short out the non-transmitting antenna, and you should sequence it so it closes a few milliseconds before beginning TX and opens a few milliseconds after ceasing TX. Even better than simple shorting, use an SPDT relay so that when the relay activated, the antenna is disconnected and the receiver input is shorted to ground, separate from the antenna. This provides even more isolation between the two.
>>
>>
>>
>> 73, Bill W6WRT
>>
>> ______________________________________________________________
>> Elecraft mailing list
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>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
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Phil Salas

Re: Antenna question

In reply to this post by George Thornton

Check out the front-end protector in the “Articles” section of my website at www.ad5x.com.

Phil – AD5X
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k6dgw

Re: Antenna question

In reply to this post by George Thornton

On 2/11/2014 3:36 PM, George Thornton wrote:
> This might be a stupid question, but here goes.

Only unasked questions are stupid.
>
> I have a small lot. I currently am using a 3 element Yagi that
> barely fits on the property. I was thinking about getting a vertical
> as a second HF antenna. If I put it up it is going to have to be
> pretty close to the Yagi.

You will likely find that a vertical <anything> will be 1-2 S-units
noisier than your horizontal yagi [or any other horizontal antenna, in
general], *unless* you have essentially *no* man-made noise. You said
"small lot" which suggests an urban or suburban environment. I have a
tri-bander, a large sloping Vee for 160-30, and a GAP Titan vertical on
the pipe that carries my coax up to the roof and to the other antennas.
I can almost always count on the GAP being a couple of S-units noiser
than the other two on any of the bands they work on.
>
> I have a dual receive K3. If I have both receivers going, one on
> each channel, and I broadcast on one of these antennas, am I in any
> danger of overloading and frying the other receiver?

Antennas <all> have a near-field and a far-field and the definition of
"near" and "far" depends on the operating frequency, among some other
things. The lower the frequency [longer wavelength], the farther "far"
is from the antenna. If a second antenna is located within the
near-field of the first, they will become a coupled system ... the
second antenna will behave as if it was an element or elements of the
first antenna. In this case, some fairly large amounts of RF power can
show up at the end of the second antennas coax. Obviously, it depends a
huge amount on the power you intend to run. 5W may safe.

If the second antenna is clearly in the far-field of the first, the
coupled power is much much lower. The signal will be huge in the second
receiver, but not likely to be damaging to components.

I'm on the crew that activates Alpine County in the Calif QSO Party [no
permanent hams there]. First year we tried M/2, we had CW and SSB in
one cabin. Considering that the aggregate ham experience of the crew
was well over 200 years, I can't explain why we did this. :-)

The 80 and 75 inverted Vee's were undoubtedly in each other's
near-fields, not sure about the 40's, but we had bandpass filters for
each rig. I was on 80 CW in the middle of the night, the phone op
decided to try 75 ... he switched the filters, I called CQ, and I fried
the diodes in the front end of his K3. We now have the two stations at
opposite ends of the campground [maybe 500 meters?], and we have no
problems.

So George, I'd be very careful. The cross-polarization would be in your
favor but if you're on 20 or below and "close" means less than a
wavelength at best, it could mean problems.

Hope this helps

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2014 Cal QSO Party 4-5 Oct 2014
- www.cqp.org

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Mike K2MK

Re: Antenna question

In reply to this post by George Thornton

Hi George,

I'm not 100% sure but I don't think your SUB RX has to be ON to be damaged. I believe that just connecting an antenna to the AUX RF input will allow RF into the SUB RX.

There is an internal protective device on the input to the SUB RX called a carrier operated relay (COR). You can see it in the manual in some of the block diagrams. When you get your vertical you can try transmitting with the yagi at low power and gradually increase your power. If you hear a clicking sound you are tripping the COR. That's your positive indication that you should either decrease power or add external protection.

There are devices available to put in your SUB RX antenna line for overload protection but you can also use the KEY OUT signal to energize a relay to disconnect your SUB RX antenna. There is also a lower current KEY OUT signal on pin 10 of the accessory connector. You can use that to trip a low current device that in turn activates a relay.

73,
Mike K2MK

George A. Thornton-2 wrote

This might be a stupid question, but here goes.

I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna. If I put it up it is going to have to be pretty close to the Yagi.

I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?

Re: Antenna question

In reply to this post by George Thornton

Since the K3 will do the QRP thing down to 100 mw, think about installing the vertical above the beam on the mast and gradually try more and more power out of the K3 until you start getting some overloading. At least you can find your answer without frying anything and some folks find QRP lots of fun. Maybe you will too!

Willis 'Cookie' Cooke, TDXS DX Chairman
K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart

________________________________
From: George Thornton <[hidden email]>
To: "'elecraft @ mailman . qth . net'" <[hidden email]>
Sent: Tuesday, February 11, 2014 5:36 PM
Subject: Re: [Elecraft] Antenna question

This might be a stupid question, but here goes.

I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna. If I put it up it is going to have to be pretty close to the Yagi.

I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?

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Jim Brown-10

Re: Antenna question

In reply to this post by George Thornton

On 2/11/2014 3:36 PM, George Thornton wrote:
> I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna.

As it happens, over the past year or so I've been engaged in a serious
modeling study that compares the performance of vertical and horizontal
antennas at mounting heights that are practical for hams in your
situation. So the real question is, what will that vertical add to your
station beside a second antenna for SO2R?

If I were in your situation, I would add an antenna only to cover bands
that the tri-bander does not. Even the best vertical is unlikely to
outperform the tribander unless you happen to be blessed with REALLY
good ground conductivity, and even then only by a dB or so at low
elevation angles. Second, if I were to add a vertical, it would be one
that is configured as a center-fed dipole, and I would add it ONLY if I
could elevate it at least 20 ft.

Yes, I know this wasn't the question you asked, but it needs to be asked
and answered. :) Also, by all means pay attention to K6DGW's comments,
with which I completely concur.

There's a link to a presentation I did last fall of the vertical height
issue, and also one about the recently popular 43 ft vertical.
http://k9yc.com/publish.htm

I'm still working on the comparison of verticals to horizontal antennas
-- I've done all the modeling and know the results, but haven't
organized it to show yet. AD5X has also done some excellent work on the
43 ft vertical idea. And QST recently published a piece showing that a
better use of a 43 ft vertical might be as the center support for
horizontal dipoles for 80 and 40, a concept with which I strongly agree. :)

73, Jim K9YC

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Edward R Cole

Re: Antenna question

In reply to this post by George Thornton

George,

You do not say what power you are transmitting and it would be
helpful to know the separation between the antennas. Will the
vertical be as high as the yagi? Need to know what frequency is used.

OK, in lieu of this data I will make some assumptions and show you
the math to calculate the power received.
F = 3.5-MHz
Po = 100w = 50 dBm
separation = 60 feet = 18.3m
cross-pol loss = 20 dB (it will not be quite this much at this close
separation)
L = 32.4 + 20 Log F + 20 Log d, where F= MHz and d= km
L = the space loss between antenna, in dB
L = 32.4 +20 Log (3.5) + 20 Log (18.3/1000)
L = 32.4 + 10.9 - 5
L = 38 dB
Ltot = L + Lcross-pol = 58 dB
Po - Ltot = -8 dBm

That is a very strong signal but will not hurt the
receiver. Typically anything under 0 dBm is safe. I run 1500w and
have a preamp attached to the TR coax relay and have had no problems
blowing up the very sensitive transistor in the preamp if the relay
isolation is equal to the power in dBm.

Now cross-pol loss is probably not 20 dB but more like 15 dB and your
antennas are in near-field so these formula are not quite
accurate. Ideally you would measure the power on the receiving
antenna with a milliwatt power meter but I suppose you do not have
one. Also I did not include antenna gains in this, but in close
proximity they are probably not accurate.

I have tested my tower mounted preamp by sending a test signal to an
antenna about 130-foot away and using the space loss formula pretty
accurately predicted received signal level. This let me test the
preamp sensitivity without removing it from the tower.

If you have a scope look at the received RF signal and measure the
peak voltage.
P = E^2*R or
E = sq-rt (P/50)
P = 0 dBm = 0.001w
sq-rt(0.001/50) = .004v

73, Ed - KL7UW
PS: If you run more than 100w then either short the receiver antenna
line or use a coax relay to disconnect it when transmitting.

------------------------
Date: Tue, 11 Feb 2014 23:36:09 +0000
From: George Thornton <[hidden email]>
To: "'elecraft @ mailman . qth . net'" <[hidden email]>
Subject: Re: [Elecraft] Antenna question
Message-ID:
<[hidden email]>
Content-Type: text/plain; charset="us-ascii"

This might be a stupid question, but here goes.

I have a small lot. I currently am using a 3 element Yagi that
barely fits on the property. I was thinking about getting a vertical
as a second HF antenna. If I put it up it is going to have to be
pretty close to the Yagi.

I have a dual receive K3. If I have both receivers going, one on
each channel, and I broadcast on one of these antennas, am I in any
danger of overloading and frying the other receiver?

73, Ed - KL7UW
http://www.kl7uw.com
"Kits made by KL7UW"
Dubus Mag business:
[hidden email]

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DL6OAP

Re: Antenna question

Hi George,

The 130 feet corresponds to lambda/2 on 80 and you can use the far field approximation (that Ed is using) there...

At short distances (less than a quarter or a sixth of the wavelength), however, 1/r^2 and 1/r^3 ("near field") components of E and H fields are still present (or dominant) and the far field approximation should not be used. You also have to be careful with the cross-polarization argument, since the electrical near field has all three vector components almost anywhere in space and the coupling can be much higher (depending on how well symmetry is preserved in the "yagi+vertical system").

Better use a NEC based program (e.g. EZNEC or the free 4nec2), if you have on access to a milliwatt-meter/scope and have to calculate...

By the way, P should read
P= E*I = E^2/R
=> E=sqrt(P*R)=223mV
for a 0dBm (S9+67dB) signal (?)

Greetings

Ralf, DL6OAP

Am 12.02.2014 um 10:31 schrieb Edward R Cole <[hidden email]>:

> George,
>
> You do not say what power you are transmitting and it would be helpful to know the separation between the antennas. Will the vertical be as high as the yagi? Need to know what frequency is used.
>
> OK, in lieu of this data I will make some assumptions and show you the math to calculate the power received.
> F = 3.5-MHz
> Po = 100w = 50 dBm
> separation = 60 feet = 18.3m
> cross-pol loss = 20 dB (it will not be quite this much at this close separation)
> L = 32.4 + 20 Log F + 20 Log d, where F= MHz and d= km
> L = the space loss between antenna, in dB
> L = 32.4 +20 Log (3.5) + 20 Log (18.3/1000)
> L = 32.4 + 10.9 - 5
> L = 38 dB
> Ltot = L + Lcross-pol = 58 dB
> Po - Ltot = -8 dBm
>
> That is a very strong signal but will not hurt the receiver. Typically anything under 0 dBm is safe. I run 1500w and have a preamp attached to the TR coax relay and have had no problems blowing up the very sensitive transistor in the preamp if the relay isolation is equal to the power in dBm.
>
> Now cross-pol loss is probably not 20 dB but more like 15 dB and your antennas are in near-field so these formula are not quite accurate. Ideally you would measure the power on the receiving antenna with a milliwatt power meter but I suppose you do not have one. Also I did not include antenna gains in this, but in close proximity they are probably not accurate.
>
> I have tested my tower mounted preamp by sending a test signal to an antenna about 130-foot away and using the space loss formula pretty accurately predicted received signal level. This let me test the preamp sensitivity without removing it from the tower.
>
> If you have a scope look at the received RF signal and measure the peak voltage.
> P = E^2*R or
> E = sq-rt (P/50)
> P = 0 dBm = 0.001w
> sq-rt(0.001/50) = .004v
>
> 73, Ed - KL7UW
> PS: If you run more than 100w then either short the receiver antenna line or use a coax relay to disconnect it when transmitting.
>
> ------------------------
> Date: Tue, 11 Feb 2014 23:36:09 +0000
> From: George Thornton <[hidden email]>
> To: "'elecraft @ mailman . qth . net'" <[hidden email]>
> Subject: Re: [Elecraft] Antenna question
> Message-ID:
> <[hidden email]>
> Content-Type: text/plain; charset="us-ascii"
>
> This might be a stupid question, but here goes.
>
> I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna. If I put it up it is going to have to be pretty close to the Yagi.
>
> I have a dual receive K3. If I have both receivers going, one on each channel, and I broadcast on one of these antennas, am I in any danger of overloading and frying the other receiver?
>
>
> 73, Ed - KL7UW
> http://www.kl7uw.com
> "Kits made by KL7UW"
> Dubus Mag business:
> [hidden email]
>
> ______________________________________________________________
> 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

George Danner

Re: Antenna question

In reply to this post by Cookie

Good advice:
I use wire antennas for 40m & 80m with a HexBeam for the higher bands & a
5BTV vertical. My sub-receiver is connected to a 50' vertical wire. The
vertical wire is about 20' (horizontally) from the wire antennas and about
30' from the 5BTV and HexBeam
When I installed the KPA500 I did the same test starting at 10 watts on 80m
through 10m. I found that there was enough isolation on all antennas to
leave the sub-receiver connected. I use the sub-receiver for diversity and
would miss that feature.
George

--------------------------------------------------
From: "WILLIS COOKE" <[hidden email]>
Sent: Tuesday, February 11, 2014 10:21 PM
To: "George Thornton" <[hidden email]>; "'elecraft @
mailman . qth . net'" <[hidden email]>
Subject: Re: [Elecraft] Antenna question

Since the K3 will do the QRP thing down to 100 mw, think about installing
the vertical above the beam on the mast and gradually try more and more
power out of the K3 until you start getting some overloading. At least you
can find your answer without frying anything and some folks find QRP lots of
fun. Maybe you will too!

Willis 'Cookie' Cooke, TDXS DX Chairman
K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart

________________________________
From: George Thornton <[hidden email]>
To: "'elecraft @ mailman . qth . net'" <[hidden email]>
Sent: Tuesday, February 11, 2014 5:36 PM
Subject: Re: [Elecraft] Antenna question

This might be a stupid question, but here goes.

I have a small lot. I currently am using a 3 element Yagi that barely fits
on the property. I was thinking about getting a vertical as a second HF
antenna. If I put it up it is going to have to be pretty close to the Yagi.

I have a dual receive K3. If I have both receivers going, one on each
channel, and I broadcast on one of these antennas, am I in any danger of
overloading and frying the other receiver?

______________________________________________________________
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George Danner

Re: Antenna question

In reply to this post by Cookie

Wes (N7WS)

Re: Antenna question

In reply to this post by Jim Brown-10

Also known as, "The worst horizontal antenna is better than the best vertical
antenna" theory. It's always worked out for me. Now if I lived on the beach.....

Wes N7WS

On 2/12/2014 12:09 AM, Jim Brown wrote:

> [snip]
> I'm still working on the comparison of verticals to horizontal antennas --
> I've done all the modeling and know the results, but haven't organized it to
> show yet. AD5X has also done some excellent work on the 43 ft vertical idea.
> And QST recently published a piece showing that a better use of a 43 ft
> vertical might be as the center support for horizontal dipoles for 80 and 40,
> a concept with which I strongly agree. :)
>
> 73, Jim K9YC
>

Jim Brown-10

Re: Antenna question

On 2/12/2014 7:29 AM, Wes (N7WS) wrote:
> Also known as, "The worst horizontal antenna is better than the best
> vertical antenna" theory. It's always worked out for me. Now if I
> lived on the beach...

Hi Wes,

Based on my model studies, I wouldn't go that far -- it depends on how
high either of the antennas are, as well as the quality of the ground.
If your criteria is low angle radiation and you have better than average
soil, a vertical dipole that's 20 ft or more above ground will beat a
low dipole. Here in the mountains, our soil is stinko, so the only band
where a vertical beats a horizontal dipole is 160M.

73, Jim K9YC
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W6NF

Re: Antenna question

When we had our place in Silver Springs, NV, our 40-meter 4-square, with
an excellent radial system, was killer. I cannot imagine anything short
of a full-size 2, possibly 3, element yagi up at least 70 feet even
coming close. I would think it would take the 3-element yagi to even
approach the F/B ratio of the 4-square.

On the beach works *real* well. Any antenna we tried at Ballenita,
Ecuador, worked great. The QTH was roughly 10-meters inland from
high-tide! :>)

Jack, W6NF/VE4SNA/HC2UA
Shelley, K7MKL/HC2UB

On 2/12/2014 3:17 PM, Jim Brown wrote:

> On 2/12/2014 7:29 AM, Wes (N7WS) wrote:
>> Also known as, "The worst horizontal antenna is better than the best
>> vertical antenna" theory. It's always worked out for me. Now if I
>> lived on the beach...
>
> Hi Wes,
>
> Based on my model studies, I wouldn't go that far -- it depends on how
> high either of the antennas are, as well as the quality of the ground.
> If your criteria is low angle radiation and you have better than
> average soil, a vertical dipole that's 20 ft or more above ground will
> beat a low dipole. Here in the mountains, our soil is stinko, so the
> only band where a vertical beats a horizontal dipole is 160M.
>
> 73, Jim K9YC
> ______________________________________________________________
> 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
>

JBaumgarte

Re: Antenna question

I love my 40 mtr 4 SQ & it's in the woods of FAR NW WI. Poor soil, good ground system (36 each vertical) and very exact construction. Antennas are surrounded by much taller aspen. I moved from a location where I had a big 2 element at 125'. It feels very similar and at 72, I'm done climbing big towers. Sure is easier to maintain/fix/adjust. For those considering, it's verybroadbanded and even has directivity on 30! Worked FT5ZM on CW and rtty on 30 using the 40 mtr 4 SQ.
It stinks for ss on 40, but great band opener for DX (further away the better).
John, N0IJ
Sent from my iPhone

> On Feb 12, 2014, at 5:34 PM, Jack <[hidden email]> wrote:
>
> When we had our place in Silver Springs, NV, our 40-meter 4-square, with an excellent radial system, was killer. I cannot imagine anything short of a full-size 2, possibly 3, element yagi up at least 70 feet even coming close. I would think it would take the 3-element yagi to even approach the F/B ratio of the 4-square.
>
> On the beach works *real* well. Any antenna we tried at Ballenita, Ecuador, worked great. The QTH was roughly 10-meters inland from high-tide! :>)
>
> Jack, W6NF/VE4SNA/HC2UA
> Shelley, K7MKL/HC2UB
>
>> On 2/12/2014 3:17 PM, Jim Brown wrote:
>>> On 2/12/2014 7:29 AM, Wes (N7WS) wrote:
>>> Also known as, "The worst horizontal antenna is better than the best vertical antenna" theory. It's always worked out for me. Now if I lived on the beach...
>>
>> Hi Wes,
>>
>> Based on my model studies, I wouldn't go that far -- it depends on how high either of the antennas are, as well as the quality of the ground. If your criteria is low angle radiation and you have better than average soil, a vertical dipole that's 20 ft or more above ground will beat a low dipole. Here in the mountains, our soil is stinko, so the only band where a vertical beats a horizontal dipole is 160M.
>>
>> 73, Jim K9YC
>> ______________________________________________________________
>> 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
>>
>
> ______________________________________________________________
> 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

Jim Rodenkirch

Re: Antenna question

In reply to this post by Jim Brown-10

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