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An Antenna Problem I Can't Figure Out

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bdrobnes

An Antenna Problem I Can't Figure Out

I am trying to temporarily use a 20 m Hamstick on my
Outbacker tripod. The base I am using checks out fine with
nothing attached. In other words, the top where the antenna screws in shorts
with the pin on the UHF connector on the bottom of the base and is isolated
from the tripod. When I connect a non-terminated coax to the base connector
everything continues to check out as above. However, as soon as I connect the
other end of the coax to ANT 1 of the K3, everything is shorted together (the
top where the antenna screws in shorts with the tripod) and the KPA500 shows
infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in Phoenix
was kind enough to exchange the Hamstick for another, with no effect. Any ideas
and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE

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daleputnam

Re: An Antenna Problem I Can't Figure Out

Hi Bill,
Just to be sure I understand, With the coax connected to the tripod, the antenna connected to the tripod, with the only connection left to connect would be the coax to the radio... if you measure across the coax there is no short? And there is conductivity from the pin to the antenna?
Just making sure I understand,
Thanks,

--... ...-- Dale - WC7S in Wy

> Date: Sat, 27 Aug 2011 18:34:32 -0700
> From: [hidden email]
> To: [hidden email]
> Subject: [Elecraft] An Antenna Problem I Can't Figure Out
>
> I am trying to temporarily use a 20 m Hamstick on my
> Outbacker tripod. The base I am using checks out fine with
> nothing attached. In other words, the top where the antenna screws in shorts
> with the pin on the UHF connector on the bottom of the base and is isolated
> from the tripod. When I connect a non-terminated coax to the base connector
> everything continues to check out as above. However, as soon as I connect the
> other end of the coax to ANT 1 of the K3, everything is shorted together (the
> top where the antenna screws in shorts with the tripod) and the KPA500 shows
> infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in Phoenix
> was kind enough to exchange the Hamstick for another, with no effect. Any ideas
> and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE
>
>
> ______________________________________________________________
> 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

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Guy, K2AV

Re: An Antenna Problem I Can't Figure Out

This sounds like a PL259 on one or the other end that is incorrectly dressed
and soldered. I would guess something wrong in the PL259 that attaches to
the K3. Before you throw the K3 in the drink, use a different piece of
coax. All it takes is a very small gap that does not show up on an
analyzer, but is arced across by 100 watts, or a short that makes contact
when you bend it to get to the K3, or yada, yada, yada.

Mechanical problems with coax, plugs, jumpers, cords and adapters, etc. are
by far the most common problem with ham setups.

73, Guy.

On Sat, Aug 27, 2011 at 9:44 PM, Dale Putnam <[hidden email]> wrote:

>
> Hi Bill,
> Just to be sure I understand, With the coax connected to the tripod, the
> antenna connected to the tripod, with the only connection left to connect
> would be the coax to the radio... if you measure across the coax there is no
> short? And there is conductivity from the pin to the antenna?
> Just making sure I understand,
> Thanks,
>
> --... ...-- Dale - WC7S in Wy
>
>
> > Date: Sat, 27 Aug 2011 18:34:32 -0700
> > From: [hidden email]
> > To: [hidden email]
> > Subject: [Elecraft] An Antenna Problem I Can't Figure Out
> >
> > I am trying to temporarily use a 20 m Hamstick on my
> > Outbacker tripod. The base I am using checks out fine with
> > nothing attached. In other words, the top where the antenna screws in
> shorts
> > with the pin on the UHF connector on the bottom of the base and is
> isolated
> > from the tripod. When I connect a non-terminated coax to the base
> connector
> > everything continues to check out as above. However, as soon as I connect
> the
> > other end of the coax to ANT 1 of the K3, everything is shorted together
> (the
> > top where the antenna screws in shorts with the tripod) and the KPA500
> shows
> > infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in
> Phoenix
> > was kind enough to exchange the Hamstick for another, with no effect. Any
> ideas
> > and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE
> >
> >
> > ______________________________________________________________
> > 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
>

bdrobnes

Re: An Antenna Problem I Can't Figure Out

Thanks Guy.The coax and connectors seem to check out OK, and I switched the coax with a brand new one and got the same result.Also, this coax worked fine with a Yaesu ATAS 120 antenna I sold (unfortunately) last weekend.73, Bill

--- On Sun, 8/28/11, Guy Olinger K2AV <[hidden email]> wrote:

From: Guy Olinger K2AV <[hidden email]>
Subject: Re: [Elecraft] An Antenna Problem I Can't Figure Out
To: "Dale Putnam" <[hidden email]>
Cc: [hidden email], "[hidden email]" <[hidden email]>
Date: Sunday, August 28, 2011, 3:57 AM

This sounds like a PL259 on one or the other end that is incorrectly dressed and soldered. I would guess something wrong in the PL259 that attaches to the K3. Before you throw the K3 in the drink, use a different piece of coax. All it takes is a very small gap that does not show up on an analyzer, but is arced across by 100 watts, or a short that makes contact when you bend it to get to the K3, or yada, yada, yada.

Mechanical problems with coax, plugs, jumpers, cords and adapters, etc. are by far the most common problem with ham setups.
73, Guy.

On Sat, Aug 27, 2011 at 9:44 PM, Dale Putnam <[hidden email]> wrote:

Hi Bill,

Just to be sure I understand, With the coax connected to the tripod, the antenna connected to the tripod, with the only connection left to connect would be the coax to the radio... if you measure across the coax there is no short? And there is conductivity from the pin to the antenna?

Just making sure I understand,

Thanks,

--... ...-- Dale - WC7S in Wy

> Date: Sat, 27 Aug 2011 18:34:32 -0700

> From: [hidden email]

> To: [hidden email]

> Subject: [Elecraft] An Antenna Problem I Can't Figure Out

>

> I am trying to temporarily use a 20 m Hamstick on my

> Outbacker tripod. The base I am using checks out fine with

> nothing attached. In other words, the top where the antenna screws in shorts

> with the pin on the UHF connector on the bottom of the base and is isolated

> from the tripod. When I connect a non-terminated coax to the base connector

> everything continues to check out as above. However, as soon as I connect the

> other end of the coax to ANT 1 of the K3, everything is shorted together (the

> top where the antenna screws in shorts with the tripod) and the KPA500 shows

> infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in Phoenix

> was kind enough to exchange the Hamstick for another, with no effect. Any ideas

> and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE

>

>

> ______________________________________________________________

> 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

______________________________________________________________

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Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html

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Don Wilhelm-4

Re: An Antenna Problem I Can't Figure Out

In reply to this post by bdrobnes

Bill,

What is the results if you connect the antenna to the K3 (without the
KPA500).
Even though it may show a DC short, that may be only at the DC
measurement. At RF, what is the impedance. An antenna analyzer
measurement may be helpful in determining the actual impedance at frequency.

Bottom line - if the antenna analyzer indicates something near 50 ohms
resistive, either the K3 or the KPA500 should operate into it with no
problem.

Look for coax connections that are not tight - finger tight is not good
enough for UHF connectors. What will be OK at low power levels may not
be OK when the power is increased to 100 or 500 watts.

73,
Don W3FPR

On 8/27/2011 9:34 PM, Bill Drobnes wrote:

> I am trying to temporarily use a 20 m Hamstick on my
> Outbacker tripod. The base I am using checks out fine with
> nothing attached. In other words, the top where the antenna screws in shorts
> with the pin on the UHF connector on the bottom of the base and is isolated
> from the tripod. When I connect a non-terminated coax to the base connector
> everything continues to check out as above. However, as soon as I connect the
> other end of the coax to ANT 1 of the K3, everything is shorted together (the
> top where the antenna screws in shorts with the tripod) and the KPA500 shows
> infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in Phoenix
> was kind enough to exchange the Hamstick for another, with no effect. Any ideas
> and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE
>

Ted Bryant

Re: An Antenna Problem I Can't Figure Out

In reply to this post by bdrobnes

Have you checked it with an antenna analyzer like an MFJ? That will show where your setup is resonant. Is the tripod sitting on grass or concrete?? It must be on grass or dirt to work properly.

73, Ted W4NZ

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of Bill Drobnes
Sent: Saturday, August 27, 2011 10:06 PM
To: Dale Putnam; Guy Olinger K2AV
Cc: [hidden email]
Subject: Re: [Elecraft] An Antenna Problem I Can't Figure Out

Thanks Guy.The coax and connectors seem to check out OK, and I switched the coax with a brand new one and got the same result.Also, this coax worked fine with a Yaesu ATAS 120 antenna I sold (unfortunately) last weekend.73, Bill

--- On Sun, 8/28/11, Guy Olinger K2AV <[hidden email]> wrote:

From: Guy Olinger K2AV <[hidden email]>
Subject: Re: [Elecraft] An Antenna Problem I Can't Figure Out
To: "Dale Putnam" <[hidden email]>
Cc: [hidden email], "[hidden email]" <[hidden email]>
Date: Sunday, August 28, 2011, 3:57 AM

This sounds like a PL259 on one or the other end that is incorrectly dressed and soldered. I would guess something wrong in the PL259 that attaches to the K3. Before you throw the K3 in the drink, use a different piece of coax. All it takes is a very small gap that does not show up on an analyzer, but is arced across by 100 watts, or a short that makes contact when you bend it to get to the K3, or yada, yada, yada.

Mechanical problems with coax, plugs, jumpers, cords and adapters, etc. are by far the most common problem with ham setups.
73, Guy.

On Sat, Aug 27, 2011 at 9:44 PM, Dale Putnam <[hidden email]> wrote:

Hi Bill,

Just to be sure I understand, With the coax connected to the tripod, the antenna connected to the tripod, with the only connection left to connect would be the coax to the radio... if you measure across the coax there is no short? And there is conductivity from the pin to the antenna?

Just making sure I understand,

Thanks,

--... ...-- Dale - WC7S in Wy

> Date: Sat, 27 Aug 2011 18:34:32 -0700

> From: [hidden email]

> To: [hidden email]

> Subject: [Elecraft] An Antenna Problem I Can't Figure Out

>

> I am trying to temporarily use a 20 m Hamstick on my

> Outbacker tripod. The base I am using checks out fine with

> nothing attached. In other words, the top where the antenna screws in shorts

> with the pin on the UHF connector on the bottom of the base and is isolated

> from the tripod. When I connect a non-terminated coax to the base connector

> everything continues to check out as above. However, as soon as I connect the

> other end of the coax to ANT 1 of the K3, everything is shorted together (the

> top where the antenna screws in shorts with the tripod) and the KPA500 shows

> infinite SWR. The Hamstick folks couldn’t figure it out and HRO here in Phoenix

> was kind enough to exchange the Hamstick for another, with no effect. Any ideas

> and/or explanations? Thanks and 73, Bill N4IEZ / F4WAE

>

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

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Phil Salas

Re: An Antenna Problem I Can't Figure Out

In reply to this post by bdrobnes

A Hamstick is a pretty narrow-band antenna and really needs to be set-up
with an SWR analyzer, otherwise you can have a hard time finding where it is
resonant. You don't have to be far off resonance (especially below 20
meters) for the SWR to be very high.

Also - check connectivity from the the coax center conductor at the radio
end to the tip of the Hamstick. That'll tell you if you have an open in the
Hamstick itself. Also, I don't believe the Hamstick can handle 500 watts -
but maybe things have changed since I used them many years ago.
But I bet the problem is that the Hamstick is resonant well-off where you
think it is (but I've been wrong before).

Phil - AD5X

______________________________________________________________
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Post: mailto:[hidden email]

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